IRIX Base Documentation 2002 November/SGI IRIX Base Documentation 2002 November.iso/usr/share/catman/u_man/cat1/sh.z/sh

Text File | 2002-10-03 | 165.1 KB | 2,839 lines

sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



NNNNAAAAMMMMEEEE
     _ssss_hhhh_,,,, _rrrr_ssss_hhhh_,,,, _kkkk_ssss_hhhh_,,,, _rrrr_kkkk_ssss_hhhh - a standard/restricted command and programming
     language

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     _ssss_hhhh [ _----_aaaa_bbbb_CCCC_eeee_ffff_hhhh_iiii_kkkk_mmmm_nnnn_pppp_rrrr_ssss_tttt_uuuu_vvvv_xxxx ] [ _----_oooo _o_p_t_i_o_n ] ... [ _----_cccc _s_t_r_i_n_g ] [ _a_r_g ... ]

     ////uuuussssrrrr////lllliiiibbbb////rrrrsssshhhh  [ _----_aaaa_bbbb_CCCC_eeee_ffff_hhhh_iiii_kkkk_mmmm_nnnn_pppp_rrrr_ssss_tttt_uuuu_vvvv_xxxx ] [ _----_oooo _o_p_t_i_o_n ] ... [ _----_cccc _s_t_r_i_n_g ]
          [ _a_r_g ... ]

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     NNNNooootttteeee:::: As of IRIX 6.4, _ssss_hhhh is the Korn shell rather than the Bourne shell.
     See _bbbb_ssss_hhhh(1) for the Bourne Shell description.  See the CCCCOOOOMMMMPPPPAAAATTTTIIIIBBBBIIIILLLLIIIITTTTYYYY
     IIIISSSSSSSSUUUUEEEESSSS section below for more detail.

     This is the internationalized _ssss_hhhh. See the _IIII_NNNN_TTTT_EEEE_RRRR_NNNN_AAAA_TTTT_IIII_OOOO_NNNN_AAAA_LLLL_IIII_ZZZZ_AAAA_TTTT_IIII_OOOO_NNNN section
     below for more detail.

     _ssss_hhhh is a command and programming language that executes commands read from
     a terminal or a file.  _////_uuuu_ssss_rrrr_////_llll_iiii_bbbb_////_rrrr_ssss_hhhh (also invoked as _rrrr_kkkk_ssss_hhhh) is a
     restricted version of the standard command interpreter _ssss_hhhh; it is used to
     set up login names and execution environments whose capabilities are more
     controlled than those of the standard shell.  See IIIInnnnvvvvooooccccaaaattttiiiioooonnnn below for
     the meaning of arguments to the shell.

   DDDDeeeeffffiiiinnnniiiittttiiiioooonnnnssss
     A _m_e_t_a_c_h_a_r_a_c_t_e_r is one of the following characters:

          _;;;;   _&&&&   _((((   _))))   _||||   _<<<<   _>>>>   newline   space   tab

     A _b_l_a_n_k is a tab or a space.  An _i_d_e_n_t_i_f_i_e_r is a sequence of letters,
     digits, or underscores starting with a letter or underscore.  Identifiers
     are used as names for _f_u_n_c_t_i_o_n_s and _v_a_r_i_a_b_l_e_s.  A _w_o_r_d is a sequence of
     _c_h_a_r_a_c_t_e_r_s separated by one or more non-quoted _m_e_t_a_c_h_a_r_a_c_t_e_r_s.

     A _c_o_m_m_a_n_d is a sequence of characters in the syntax of the shell
     language.  The shell reads each command and carries out the desired
     action either directly or by invoking separate utilities.  A special
     command is a command that is carried out by the shell without creating a
     separate process.  Except for documented side effects, most special
     commands can be implemented as separate utilities.

   CCCCoooommmmmmmmaaaannnnddddssss
     A _s_i_m_p_l_e-_c_o_m_m_a_n_d is a sequence of _b_l_a_n_k separated words which may be
     preceded by a variable assignment list (see EEEEnnnnvvvviiiirrrroooonnnnmmmmeeeennnntttt below).  The
     first word specifies the name of the command to be executed.  Except as
     specified below, the remaining words are passed as arguments to the
     invoked command.  The command name is passed as argument 0 [see _eeee_xxxx_eeee_cccc(2)].
     The _v_a_l_u_e of a simple-command is its exit status if it terminates
     normally, or (octal) 200+_s_t_a_t_u_s if it terminates abnormally [see
     _ssss_iiii_gggg_nnnn_aaaa_llll(2) for a list of _s_t_a_t_u_s values].




                                                                        PPPPaaaaggggeeee 1111






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     A _p_i_p_e_l_i_n_e is a sequence of one or more _c_o_m_m_a_n_d_s separated by _||||.  The
     standard output of each command but the last is connected by a _pppp_iiii_pppp_eeee(2) to
     the standard input of the next command.  Each command is run as a
     separate process; the shell waits for the last command to terminate.  The
     exit status of a pipeline is the exit status of the last command.

     A _l_i_s_t is a sequence of one or more pipelines separated by _;;;;, _&&&&, _&&&&_&&&&, or
     _||||_||||, and optionally terminated by _;;;;, _&&&&, or _||||_&&&&.  Of these five symbols, _;;;;,
     _&&&&, and _||||_&&&& have equal precedence, which is lower than that of _&&&&_&&&& and _||||_||||.
     The symbols _&&&&_&&&& and _||||_|||| also have equal precedence.  A semicolon (_;;;;) causes
     sequential execution of the preceding pipeline; an ampersand (_&&&&) causes
     asynchronous execution of the preceding pipeline (that is, the shell does
     not wait for that pipeline to finish).  The symbol _||||_&&&& causes asynchronous
     execution of the preceding command or pipeline with a two-way pipe
     established to the parent shell.  The standard input and output of the
     spawned command can be written to and read from by the parent shell using
     the _----_pppp option of the special commands _rrrr_eeee_aaaa_dddd and _pppp_rrrr_iiii_nnnn_tttt described later.
     The symbol _&&&&_&&&& (_||||_||||) causes the _l_i_s_t following it to be executed only if
     the preceding pipeline returns a zero (nonzero) value.  An arbitrary
     number of newlines may appear in a _l_i_s_t, instead of a semicolon, to
     delimit a command.

     A _c_o_m_m_a_n_d is either a simple-command or one of the following.  Unless
     otherwise stated, the value returned by a command is that of the last
     simple-command executed in the command.

     _ffff_oooo_rrrr _i_d_e_n_t_i_f_i_e_r [ _iiii_nnnn _w_o_r_d ... ] _;;;; _dddd_oooo _l_i_s_t _;;;; _dddd_oooo_nnnn_eeee
          Each time a _ffff_oooo_rrrr command is executed, _i_d_e_n_t_i_f_i_e_r is set to the next
          _w_o_r_d taken from the _iiii_nnnn _w_o_r_d list.  If _iiii_nnnn _w_o_r_d ...  is omitted, the
          _ffff_oooo_rrrr command executes the _dddd_oooo _l_i_s_t once for each positional parameter
          that is set (see PPPPaaaarrrraaaammmmeeeetttteeeerrrr SSSSuuuubbbbssssttttiiiittttuuuuttttiiiioooonnnn below).  Execution ends when
          there are no more words in the list.

     _ssss_eeee_llll_eeee_cccc_tttt _i_d_e_n_t_i_f_i_e_r [ _iiii_nnnn _w_o_r_d ... ] _;;;; _dddd_oooo _l_i_s_t _;;;; _dddd_oooo_nnnn_eeee
          A _ssss_eeee_llll_eeee_cccc_tttt command prints on standard error (file descriptor 2), the
          set of _w_o_r_ds, each preceded by a number.  If _iiii_nnnn _w_o_r_d ...  is
          omitted, the positional parameters are used instead (see PPPPaaaarrrraaaammmmeeeetttteeeerrrr
          SSSSuuuubbbbssssttttiiiittttuuuuttttiiiioooonnnn below).  The _PPPP_SSSS_3333 prompt is printed and a line is read
          from the standard input.  If this line consists of the number of one
          of the listed _w_o_r_ds, the value of the parameter _i_d_e_n_t_i_f_i_e_r is set to
          the _w_o_r_d corresponding to this number.  If this line is empty the
          selection list is printed again.  Otherwise the value of the
          parameter _i_d_e_n_t_i_f_i_e_r is set to _nnnn_uuuu_llll_llll.  The contents of the line read
          from standard input is saved in the variable _RRRR_EEEE_PPPP_LLLL_YYYY_....  The _l_i_s_t is
          executed for each selection until a _bbbb_rrrr_eeee_aaaa_kkkk or end-of-file is
          encountered.

     _cccc_aaaa_ssss_eeee _w_o_r_d _iiii_nnnn [ [_((((]_p_a_t_t_e_r_n [ | _p_a_t_t_e_r_n ] ... _)))) _l_i_s_t _;;;;_;;;; ] ... _eeee_ssss_aaaa_cccc
          A _cccc_aaaa_ssss_eeee command executes the _l_i_s_t associated with the first _p_a_t_t_e_r_n
          that matches _w_o_r_d.  The form of the patterns is the same as that
          used for file-name generation (see FFFFiiiilllleeeennnnaaaammmmeeee GGGGeeeennnneeeerrrraaaattttiiiioooonnnn below).




                                                                        PPPPaaaaggggeeee 2222






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _iiii_ffff _l_i_s_t _;;;; _tttt_hhhh_eeee_nnnn _l_i_s_t [ _eeee_llll_iiii_ffff _l_i_s_t _;;;; _tttt_hhhh_eeee_nnnn _l_i_s_t ] ... [ _;;;; _eeee_llll_ssss_eeee _l_i_s_t ] _;;;; _ffff_iiii
          The _l_i_s_t following _iiii_ffff is executed and, if it returns a zero exit
          status, the _l_i_s_t following the first _tttt_hhhh_eeee_nnnn is executed.  Otherwise,
          the _l_i_s_t following _eeee_llll_iiii_ffff is executed and, if its value is zero, the
          _l_i_s_t following the next _tttt_hhhh_eeee_nnnn is executed.  Failing that, the _eeee_llll_ssss_eeee
          _l_i_s_t is executed.  If no _eeee_llll_ssss_eeee _l_i_s_t or _tttt_hhhh_eeee_nnnn _l_i_s_t is executed, the _iiii_ffff
          command returns a zero exit status.

     _wwww_hhhh_iiii_llll_eeee _l_i_s_t _;;;; _dddd_oooo _l_i_s_t _;;;; _dddd_oooo_nnnn_eeee
     _uuuu_nnnn_tttt_iiii_llll _l_i_s_t _;;;; _dddd_oooo _l_i_s_t _;;;; _dddd_oooo_nnnn_eeee
          A _wwww_hhhh_iiii_llll_eeee command repeatedly executes the _wwww_hhhh_iiii_llll_eeee _l_i_s_t and, if the exit
          status of the last command in the list is zero, executes the _dddd_oooo
          _l_i_s_t; otherwise the loop terminates.  If no commands in the _dddd_oooo _l_i_s_t
          are executed, the _wwww_hhhh_iiii_llll_eeee command returns a zero exit status; _uuuu_nnnn_tttt_iiii_llll
          may be used in place of _wwww_hhhh_iiii_llll_eeee to negate the loop termination test.

     _((((_l_i_s_t_))))
          Execute _l_i_s_t in a separate environment.  Note, that if two adjacent
          open parentheses are needed for nesting, a space must be inserted to
          avoid arithmetic evaluation as described below.

     _{{{{ _l_i_s_t_;;;;_}}}}
          _l_i_s_t is simply executed.  The _{{{{ must be followed by a space.  Note
          that unlike the metacharacters _(((( and _)))), _{{{{ and _}}}} are _r_e_s_e_r_v_e_d _w_o_r_ds
          and must be typed at the beginning of a line or after a _;;;; in order
          to be recognized.

     _[[[[_[[[[_e_x_p_r_e_s_s_i_o_n_]]]]_]]]]
          Evaluates _e_x_p_r_e_s_s_i_o_n and returns a zero exit status when _e_x_p_r_e_s_s_i_o_n
          is true.  See CCCCoooonnnnddddiiiittttiiiioooonnnnaaaallll EEEExxxxpppprrrreeeessssssssiiiioooonnnnssss below, for a description of
          _e_x_p_r_e_s_s_i_o_n.

     _ffff_uuuu_nnnn_cccc_tttt_iiii_oooo_nnnn _i_d_e_n_t_i_f_i_e_r _{{{{ _l_i_s_t_;;;;_}}}}
     _i_d_e_n_t_i_f_i_e_r _((((_)))) _{{{{ _l_i_s_t_;;;;_}}}}
          Define a function which is referenced by _i_d_e_n_t_i_f_i_e_r.  The body of
          the function is the _l_i_s_t of commands between _{{{{ and _}}}} (see FFFFuuuunnnnccccttttiiiioooonnnnssss
          below).  The _{{{{ must be followed by a space.

     _tttt_iiii_mmmm_eeee _p_i_p_e_l_i_n_e
          The _p_i_p_e_l_i_n_e is executed and the elapsed time as well as the user
          and system time are printed on standard error.  Note that the
          reported times reflect the elapsed time for both the parent and the
          child processes in order to give a more accurate view of the total
          time the _p_i_p_e_l_i_n_e took to execute.

     The following reserved words are only recognized as the first word of a
     command and when not quoted:

          _iiii_ffff _tttt_hhhh_eeee_nnnn _eeee_llll_ssss_eeee _eeee_llll_iiii_ffff _ffff_iiii _cccc_aaaa_ssss_eeee _eeee_ssss_aaaa_cccc _ffff_oooo_rrrr _wwww_hhhh_iiii_llll_eeee _uuuu_nnnn_tttt_iiii_llll _dddd_oooo _dddd_oooo_nnnn_eeee _{{{{ _}}}}
          _ffff_uuuu_nnnn_cccc_tttt_iiii_oooo_nnnn _ssss_eeee_llll_eeee_cccc_tttt _tttt_iiii_mmmm_eeee _[[[[_[[[[ _]]]]_]]]]





                                                                        PPPPaaaaggggeeee 3333






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



   CCCCoooommmmmmmmeeeennnnttttssss
     A word beginning with _#### causes that word and all the following characters
     up to a newline to be ignored.

   AAAAlllliiiiaaaassssiiiinnnngggg
     The first word of each command is replaced by the text of an _aaaa_llll_iiii_aaaa_ssss if an
     _aaaa_llll_iiii_aaaa_ssss for this word has been defined.  An alias name consists of any
     number of characters excluding meta-characters, quoting characters, file
     expansion characters, parameter and command substitution characters and
     _====.  The replacement string can contain any valid shell script including
     the metacharacters listed above.  The first word of each command in the
     replaced text, other than any that are in the process of being replaced,
     is tested for aliases.  If the last character of the alias value is a
     _b_l_a_n_k the word following the alias is also checked for alias
     substitution.  Aliases can be used to redefine special builtin commands
     but cannot be used to redefine the reserved words listed above.  Aliases
     can be created, listed, and exported with the _aaaa_llll_iiii_aaaa_ssss command and can be
     removed with the _uuuu_nnnn_aaaa_llll_iiii_aaaa_ssss command.  Exported aliases remain in effect for
     scripts invoked by name, but must be reinitialized for separate
     invocations of the shell (see IIIInnnnvvvvooooccccaaaattttiiiioooonnnn below).

     _A_l_i_a_s_i_n_g is performed when scripts are read, not while they are executed.
     Therefore, for an alias to take effect the _aaaa_llll_iiii_aaaa_ssss definition command has
     to be executed before the command which references the alias is read.

     Aliases are frequently used as a short hand for full pathnames.  An
     option to the aliasing facility allows the value of the alias to be
     automatically set to the full pathname of the corresponding command.
     These aliases are called tracked aliases.  The value of a tracked alias
     is defined the first time the corresponding command is looked up and
     becomes undefined each time the _PPPP_AAAA_TTTT_HHHH variable is reset.  These aliases
     remain tracked so that the next subsequent reference redefines the value.
     Several tracked aliases are compiled into the shell.  The _----_hhhh option of
     the _ssss_eeee_tttt command makes each referenced command name into a tracked alias.

     The following _e_x_p_o_r_t_e_d _a_l_i_a_s_e_s are compiled into the shell but can be
     unset or redefined:

          _aaaa_uuuu_tttt_oooo_llll_oooo_aaaa_dddd_====_''''_tttt_yyyy_pppp_eeee_ssss_eeee_tttt _----_ffff_uuuu_''''
          _ffff_aaaa_llll_ssss_eeee_====_''''_llll_eeee_tttt _0000_''''
          _ffff_uuuu_nnnn_cccc_tttt_iiii_oooo_nnnn_ssss_====_''''_tttt_yyyy_pppp_eeee_ssss_eeee_tttt _----_ffff_''''
          _hhhh_aaaa_ssss_hhhh_====_''''_aaaa_llll_iiii_aaaa_ssss _----_tttt_''''
          _hhhh_iiii_ssss_tttt_oooo_rrrr_yyyy_====_''''_ffff_cccc _----_llll_''''
          _iiii_nnnn_tttt_eeee_gggg_eeee_rrrr_====_''''_tttt_yyyy_pppp_eeee_ssss_eeee_tttt _----_iiii_''''
          _nnnn_oooo_hhhh_uuuu_pppp_====_''''_nnnn_oooo_hhhh_uuuu_pppp _''''
          _rrrr_====_''''_ffff_cccc _----_eeee _----_''''
          _tttt_rrrr_uuuu_eeee_====_''''_::::_''''
          _tttt_yyyy_pppp_eeee_====_''''_wwww_hhhh_eeee_nnnn_cccc_eeee _----_vvvv_''''







                                                                        PPPPaaaaggggeeee 4444






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



   TTTTiiiillllddddeeee SSSSuuuubbbbssssttttiiiittttuuuuttttiiiioooonnnn
     After alias substitution is performed, each word is checked to see if it
     begins with an unquoted _~~~~.  If it does, the word up to a _//// is checked to
     see if it matches a user name in the _////_eeee_tttt_cccc_////_pppp_aaaa_ssss_ssss_wwww_dddd file.  If a match is
     found, the _~~~~ and the matched login name is replaced by the login
     directory of the matched user.  This is called a _t_i_l_d_e substitution.  If
     no match is found, the original text is left unchanged.  A _~~~~ by itself,
     or in front of a _////, is replaced by _$$$$_HHHH_OOOO_MMMM_EEEE.  A _~~~~ followed by a _++++ or _---- is
     replaced by _$$$$_PPPP_WWWW_DDDD and _$$$$_OOOO_LLLL_DDDD_PPPP_WWWW_DDDD respectively.

     In addition, _t_i_l_d_e substitution is attempted when the value of a _v_a_r_i_a_b_l_e
     _a_s_s_i_g_n_m_e_n_t begins with a _~~~~.

     Tilde substitution is not supported in all shell invocations.  (See the
     _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document.)

   CCCCoooommmmmmmmaaaannnndddd SSSSuuuubbbbssssttttiiiittttuuuuttttiiiioooonnnn
     The standard output from a command enclosed in parentheses preceded by a
     dollar sign ( _$$$$_((((_)))) ) or a pair of grave accents (_````_````) may be used as part
     or all of a word; trailing newlines are removed.  In the second (archaic)
     form, the string between the quotes is processed for special quoting
     characters before the command is executed (see QQQQuuuuoooottttiiiinnnngggg below).  Not all
     forms of command substitution are supported in all shell invocations.
     (See the _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document.) The
     command substitution _$$$$_((((_cccc_aaaa_tttt _ffff_iiii_llll_eeee_)))) can be replaced by the equivalent but
     faster _$$$$_((((_<<<<_ffff_iiii_llll_eeee_)))).  Command substitution of most special commands that do
     not perform input/output redirection are carried out without creating a
     separate process.

     In some shell invocations, an arithmetic expression enclosed in double
     parentheses and preceded by a dollar sign [_$$$$_((((_((((_))))_))))] is replaced by the
     value of the arithmetic expression within the double parentheses.  (See
     the _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document for more
     detail.)

   PPPPaaaarrrraaaammmmeeeetttteeeerrrr SSSSuuuubbbbssssttttiiiittttuuuuttttiiiioooonnnn
     A _p_a_r_a_m_e_t_e_r is an _i_d_e_n_t_i_f_i_e_r, one or more digits, or any of the
     characters _****, _@@@@, _####, _????, _----, _$$$$, and _!!!!.  A _v_a_r_i_a_b_l_e (a parameter denoted by
     an identifier) has a _v_a_l_u_e and zero or more _a_t_t_r_i_b_u_t_e_s.  _V_a_r_i_a_b_l_e_s can be
     assigned _vvvv_aaaa_llll_uuuu_eeee_ssss and _a_t_t_r_i_b_u_t_e_s by using the _tttt_yyyy_pppp_eeee_ssss_eeee_tttt special command.  The
     attributes supported by the shell are described later with the _tttt_yyyy_pppp_eeee_ssss_eeee_tttt
     special command.  Exported parameters pass values and attributes to the
     environment.

     The shell supports a one-dimensional array facility.  An element of an
     array variable is referenced by a _s_u_b_s_c_r_i_p_t.  A _s_u_b_s_c_r_i_p_t is denoted by a
     _[[[[, followed by an _a_r_i_t_h_m_e_t_i_c _e_x_p_r_e_s_s_i_o_n (see AAAArrrriiiitttthhhhmmmmeeeettttiiiicccc EEEEvvvvaaaalllluuuuaaaattttiiiioooonnnn below)
     followed by a _]]]].  To assign values to an array, use

          _ssss_eeee_tttt _----_AAAA _n_a_m_e _v_a_l_u_e _...._...._....

     The value of all subscripts must be in the range of 0 through 1023.



                                                                        PPPPaaaaggggeeee 5555






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     Arrays need not be declared.  Any reference to a variable with a valid
     subscript is legal and an array is created if necessary.  Referencing an
     array without a subscript is equivalent to referencing the element zero.

     The _v_a_l_u_e of a _v_a_r_i_a_b_l_e may also be assigned by writing:

          _n_a_m_e_====_v_a_l_u_e [ _n_a_m_e_====_v_a_l_u_e ] ...

     If the integer attribute, _----_iiii, is set for _n_a_m_e the _v_a_l_u_e is subject to
     arithmetic evaluation as described below.

     Positional parameters, parameters denoted by a number, may be assigned
     values with the _ssss_eeee_tttt special command.  Parameter _$$$$_0000 is set from argument
     zero when the shell is invoked.

     The character _$$$$ is used to introduce substitutable _p_a_r_a_m_e_t_e_r_s.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_}}}}
          The shell reads all the characters from _$$$$_{{{{ to the matching _}}}} as part
          of the same word even if it contains braces or metacharacters.  The
          value, if any, of the parameter is substituted.  The braces are
          required when _p_a_r_a_m_e_t_e_r is followed by a letter, digit, or
          underscore that is not to be interpreted as part of its name or when
          a variable is subscripted.  If _p_a_r_a_m_e_t_e_r is one or more digits it is
          a positional parameter.  A positional parameter of more than one
          digit must be enclosed in braces.  If _p_a_r_a_m_e_t_e_r is _**** or _@@@@, all the
          positional parameters, starting with _$$$$_1111, are substituted (separated
          by a field separator character).  If an array _i_d_e_n_t_i_f_i_e_r with
          subscript _**** or _@@@@ is used, the value for each of the elements is
          substituted (separated by a field separator character).

     _$$$$_{{{{_####_p_a_r_a_m_e_t_e_r_}}}}
          If _p_a_r_a_m_e_t_e_r is _**** or _@@@@, the number of positional parameters is
          substituted.  Otherwise, the length of the value of the _p_a_r_a_m_e_t_e_r is
          substituted.

     _$$$$_{{{{_####_i_d_e_n_t_i_f_i_e_r_[[[[_****_]]]]_}}}}
          The number of elements in the array _i_d_e_n_t_i_f_i_e_r is substituted.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_::::_----_w_o_r_d_}}}}
          If _p_a_r_a_m_e_t_e_r is set and is non-null, substitute its value; otherwise
          substitute _w_o_r_d.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_::::_====_w_o_r_d_}}}}
          If _p_a_r_a_m_e_t_e_r is not set or is null, set it to _w_o_r_d; the value of the
          parameter is substituted.  Positional parameters may not be assigned
          to in this way.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_::::_????_w_o_r_d_}}}}
          If _p_a_r_a_m_e_t_e_r is set and is non-null, substitute its value;
          otherwise, print _w_o_r_d and exit from the shell.  If _w_o_r_d is omitted,
          a standard message is printed.



                                                                        PPPPaaaaggggeeee 6666






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_::::_++++_w_o_r_d_}}}}
          If _p_a_r_a_m_e_t_e_r is set and is non-null, substitute _w_o_r_d; otherwise
          substitute nothing.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_####_p_a_t_t_e_r_n_}}}}
     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_####_####_p_a_t_t_e_r_n_}}}}
          If the shell _p_a_t_t_e_r_n matches the beginning of the value of
          _p_a_r_a_m_e_t_e_r, the value of this substitution is the value of the
          _p_a_r_a_m_e_t_e_r with the matched portion deleted; otherwise the value of
          this _p_a_r_a_m_e_t_e_r is substituted.  In the first form the smallest
          matching pattern is deleted and in the second form the largest
          matching pattern is deleted.

     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_%%%%_p_a_t_t_e_r_n_}}}}
     _$$$$_{{{{_p_a_r_a_m_e_t_e_r_%%%%_%%%%_p_a_t_t_e_r_n_}}}}
          If the shell _p_a_t_t_e_r_n matches the end of the value of _p_a_r_a_m_e_t_e_r, the
          value of this substitution is the value of the _p_a_r_a_m_e_t_e_r with the
          matched part deleted; otherwise substitute the value of _p_a_r_a_m_e_t_e_r.
          In the first form the smallest matching pattern is deleted and in
          the second form the largest matching pattern is deleted.

     In the above, _w_o_r_d is not evaluated unless it is to be used as the
     substituted string, so that, in the following example, _pppp_wwww_dddd is executed
     only if _dddd is not set or is null:

          _eeee_cccc_hhhh_oooo _$$$$_{{{{_dddd_::::_----_$$$$_((((_pppp_wwww_dddd_))))_}}}}

     If the colon (_::::) is omitted from the above expressions, the shell only
     checks whether _p_a_r_a_m_e_t_e_r is set or not.

     The following parameters are automatically set by the shell:

     _####        The number of positional parameters in decimal.

     _----        Flags supplied to the shell on invocation or by the _ssss_eeee_tttt command.

     _????        The decimal value returned by the last executed command.

     _$$$$        The process number of this shell.

     _____        Initially, the value _____ is an absolute pathname of the shell or
              script being executed as passed in the _e_n_v_i_r_o_n_m_e_n_t.
              Subsequently it is assigned the last argument of the previous
              command.  This parameter is not set for commands which are
              asynchronous.  This parameter is also used to hold the name of
              the matching _MMMM_AAAA_IIII_LLLL file when checking for mail.

     _!!!!        The process number of the last background command invoked.

     _EEEE_RRRR_RRRR_NNNN_OOOO    The value of _e_r_r_n_o as set by the most recently failed system
              call.  This value is system dependent and is intended for
              debugging purposes.



                                                                        PPPPaaaaggggeeee 7777






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _LLLL_IIII_NNNN_EEEE_NNNN_OOOO   The line number of the current line within the script or
              function being executed.

     _OOOO_LLLL_DDDD_PPPP_WWWW_DDDD   The previous working directory set by the _cccc_dddd command.

     _OOOO_PPPP_TTTT_AAAA_RRRR_GGGG   The value of the last option argument processed by the _gggg_eeee_tttt_oooo_pppp_tttt_ssss
              special command.

     _OOOO_PPPP_TTTT_IIII_NNNN_DDDD   The index of the last option argument processed by the _gggg_eeee_tttt_oooo_pppp_tttt_ssss
              special command.

     _PPPP_PPPP_IIII_DDDD     The process number of the parent of the shell.

     _PPPP_WWWW_DDDD      The present working directory set by the _cccc_dddd command.

     _RRRR_AAAA_NNNN_DDDD_OOOO_MMMM   Each time this variable is referenced, a random integer,
              uniformly distributed between 0 and 32767, is generated.  The
              sequence of random numbers can be initialized by assigning a
              numeric value to _RRRR_AAAA_NNNN_DDDD_OOOO_MMMM.

     _RRRR_EEEE_PPPP_LLLL_YYYY    This variable is set by the _ssss_eeee_llll_eeee_cccc_tttt statement and by the _rrrr_eeee_aaaa_dddd
              special command when no arguments are supplied.

     _SSSS_EEEE_CCCC_OOOO_NNNN_DDDD_SSSS  Each time this variable is referenced, the number of seconds
              since shell invocation is returned.  If this variable is
              assigned a value, the value returned upon reference is the value
              that was assigned plus the number of seconds since the
              assignment.

     The following variables are used by the shell:

     _CCCC_DDDD_PPPP_AAAA_TTTT_HHHH      The search path for the _cccc_dddd command.

     _CCCC_OOOO_LLLL_UUUU_MMMM_NNNN_SSSS     If this variable is set, the value is used to define the
                 width of the edit window for the shell edit modes and for
                 printing _ssss_eeee_llll_eeee_cccc_tttt lists.

     _EEEE_DDDD_IIII_TTTT_OOOO_RRRR      If the value of this variable ends in _e_m_a_c_s, or _vvvv_iiii and the
                 _VVVV_IIII_SSSS_UUUU_AAAA_LLLL variable is not set, the corresponding option (see
                 special command _ssss_eeee_tttt below) is turned on.

     _EEEE_NNNN_VVVV         If this variable is set, parameter substitution is performed
                 on the value to generate the pathname of the script that will
                 be executed when the _s_h_e_l_l is invoked (see Invocation below).
                 This file is typically used for _a_l_i_a_s and _f_u_n_c_t_i_o_n
                 definitions.

     _FFFF_CCCC_EEEE_DDDD_IIII_TTTT      The default editor name for the _ffff_cccc command.

     _FFFF_PPPP_AAAA_TTTT_HHHH       The search path for function definitions.  This path is
                 searched when a function with the _----_uuuu attribute is referenced
                 and when a command is not found.  If an executable file is



                                                                        PPPPaaaaggggeeee 8888






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



                 found, it is read and executed in the current environment.

     _IIII_FFFF_SSSS         Internal field separators (normally space, tab, and newline)
                 used to separate command words that result from command or
                 parameter substitution and for separating words with the
                 special command _rrrr_eeee_aaaa_dddd.  The first character of the _IIII_FFFF_SSSS
                 variable is used to separate arguments for the _""""_$$$$_****_""""
                 substitution (see Quoting below).

     _HHHH_IIII_SSSS_TTTT_FFFF_IIII_LLLL_EEEE    If this variable is set when the shell is invoked, the value
                 is the pathname of the file that is used to store the command
                 history (see Command re-entry below).

     _HHHH_IIII_SSSS_TTTT_SSSS_IIII_ZZZZ_EEEE    If this variable is set when the shell is invoked, the number
                 of previously entered commands that are accessible by this
                 shell is greater than or equal to this number.  The default
                 is 128.

     _HHHH_OOOO_MMMM_EEEE        The default argument (home directory) for the _cccc_dddd command.

     _LLLL_IIII_NNNN_EEEE_SSSS       If this variable is set, the value is used to determine the
                 column length for printing _ssss_eeee_llll_eeee_cccc_tttt lists.  Select lists print
                 vertically until about two-thirds of _LLLL_IIII_NNNN_EEEE_SSSS lines are filled.

     _MMMM_AAAA_IIII_LLLL        If this variable is set to the name of a mail file _a_n_d the
                 _MMMM_AAAA_IIII_LLLL_PPPP_AAAA_TTTT_HHHH variable is not set, the shell informs the user of
                 arrival of mail in the specified file.

     _MMMM_AAAA_IIII_LLLL_CCCC_HHHH_EEEE_CCCC_KKKK   This variable specifies how often (in seconds) the shell
                 checks for changes in the modification time of any of the
                 files specified by the _MMMM_AAAA_IIII_LLLL_PPPP_AAAA_TTTT_HHHH or _MMMM_AAAA_IIII_LLLL variables.  The
                 default value is 600 seconds.  When the time has elapsed, the
                 shell checks before issuing the next prompt.

     _MMMM_AAAA_IIII_LLLL_PPPP_AAAA_TTTT_HHHH    A colon ( _:::: ) separated list of filenames.  If this variable
                 is set the shell informs the user of any modifications to the
                 specified files that have occurred within the last _MMMM_AAAA_IIII_LLLL_CCCC_HHHH_EEEE_CCCC_KKKK
                 seconds.  Each filename can be followed by a _????  and a message
                 that is printed.  The message undergoes parameter
                 substitution with the variable, _$$$$_____ defined as the name of the
                 file that has changed.  The default message is _yyyy_oooo_uuuu _hhhh_aaaa_vvvv_eeee _mmmm_aaaa_iiii_llll
                 _iiii_nnnn _$$$$_____.

     _PPPP_AAAA_TTTT_HHHH        The search path for commands (see Execution below).  The user
                 may not change _PPPP_AAAA_TTTT_HHHH if executing under _rrrr_ssss_hhhh (except in
                 _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee).

     _PPPP_SSSS_1111         The value of this variable is expanded for parameter
                 substitution to define the primary prompt string which by
                 default is ``_$$$$ ''.  The character _!!!!  in the primary prompt
                 string is replaced by the _c_o_m_m_a_n_d number (see Command Re-
                 entry below).



                                                                        PPPPaaaaggggeeee 9999






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _PPPP_SSSS_2222         Secondary prompt string, by default ``_>>>> ''.

     _PPPP_SSSS_3333         Selection prompt string used within a _ssss_eeee_llll_eeee_cccc_tttt loop, by default
                 ``_####_???? ''.

     _PPPP_SSSS_4444         The value of this variable is expanded for parameter
                 substitution and precedes each line of an execution trace.
                 If omitted, the execution trace prompt is ``_++++ ''.

     _SSSS_HHHH_EEEE_LLLL_LLLL       The pathname of the _s_h_e_l_l is kept in the environment.  At
                 invocation, if the basename of this variable matches the
                 pattern _****_rrrr_****_ssss_hhhh, the shell becomes restricted.

     _TTTT_MMMM_OOOO_UUUU_TTTT       If set to a value greater than zero, the shell terminates if
                 a command is not entered within the prescribed number of
                 seconds after issuing the _PPPP_SSSS_1111 prompt.  (Note that the shell
                 can be compiled with a maximum bound for this value which
                 cannot be exceeded.)

     _VVVV_IIII_SSSS_UUUU_AAAA_LLLL      If the value of this variable ends in _e_m_a_c_s, or _vvvv_iiii the
                 corresponding option (see special command _ssss_eeee_tttt below) is
                 turned on.

     ______XXXX_PPPP_GGGG        The value of this variable controls certain features of the
                 shell. The default value is 0 (zero).  (See the _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY
                 _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document.)

     The shell gives default values to _PPPP_AAAA_TTTT_HHHH, _PPPP_SSSS_1111, _PPPP_SSSS_2222, _MMMM_AAAA_IIII_LLLL_CCCC_HHHH_EEEE_CCCC_KKKK, ______XXXX_PPPP_GGGG, _TTTT_MMMM_OOOO_UUUU_TTTT
     and _IIII_FFFF_SSSS.  _HHHH_OOOO_MMMM_EEEE, _MMMM_AAAA_IIII_LLLL and _SSSS_HHHH_EEEE_LLLL_LLLL are set by _llll_oooo_gggg_iiii_nnnn(1).

   BBBBllllaaaannnnkkkk IIIInnnntttteeeerrrrpppprrrreeeettttaaaattttiiiioooonnnn
     After parameter and command substitution, the results of substitutions
     are scanned for the field separator characters ( those found in _IIII_FFFF_SSSS ) and
     split into distinct arguments where such characters are found.  Explicit
     null arguments (_""""_"""" or _''''_'''') are retained.  Implicit null arguments (those
     resulting from _p_a_r_a_m_e_t_e_r_s that have no values) are removed.

   FFFFiiiilllleeeennnnaaaammmmeeee GGGGeeeennnneeeerrrraaaattttiiiioooonnnn
     Following substitution, each command _w_o_r_d is scanned for the characters
     _****, _????, and _[[[[ unless the _----_ffff option has been _ssss_eeee_tttt.  If one of these
     characters appears, the word is regarded as a _p_a_t_t_e_r_n.  The word is
     replaced with lexicographically sorted filenames that match the pattern.
     If no filename is found that matches the pattern, the word is left
     unchanged.  When a _p_a_t_t_e_r_n is used for filename generation, the character
     _....  at the start of a filename or immediately following a _////, as well as
     the character _//// itself, must be matched explicitly.  In other instances
     of pattern matching the _//// and _....  are not treated specially.

     _****       Matches any string, including the null string.






                                                                       PPPPaaaaggggeeee 11110000






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _????       Matches any single character.

     _[[[[..._]]]]   Matches any one of the enclosed characters.  A pair of characters
             separated by _---- matches any character lexically between the pair,
             inclusive.  If the first character following the opening "[ " is
             a "!" any character not enclosed is matched.  A _---- can be included
             in the character set by putting it as the first or last
             character.

     A _p_a_t_t_e_r_n-_l_i_s_t is a list of one or more patterns separated from each
     other with a _||||.  Composite patterns can be formed with one or more of the
     following:

     _????_((((_p_a_t_t_e_r_n-_l_i_s_t_))))   Optionally matches any one of the given patterns.

     _****_((((_p_a_t_t_e_r_n-_l_i_s_t_))))   Matches zero or more occurrences of the given patterns.

     _++++_((((_p_a_t_t_e_r_n-_l_i_s_t_))))   Matches one or more occurrences of the given patterns.

     _@@@@_((((_p_a_t_t_e_r_n-_l_i_s_t_))))   Matches exactly one of the given patterns.

     _!!!!_((((_p_a_t_t_e_r_n-_l_i_s_t_))))   Matches anything, except one of the given patterns.

   QQQQuuuuoooottttiiiinnnngggg
     Each of the _m_e_t_a_c_h_a_r_a_c_t_e_r_s listed above (see Definitions above) has a
     special meaning to the shell and causes termination of a word unless
     quoted.  A character may be _q_u_o_t_e_d (that is, made to stand for itself) by
     preceding it with a _\\\\.  The pair _\\\\_nnnn_eeee_wwww_llll_iiii_nnnn_eeee is removed.  All characters
     enclosed between a pair of single quote marks (_''''_''''), are quoted.  A single
     quote cannot appear within single quotes.  Inside double quote marks
     (_""""_""""), parameter and command substitution occurs and _\\\\ quotes the
     characters _\\\\, _````, _"""", and _$$$$.  The meaning of _$$$$_**** and _$$$$_@@@@ is identical when
     not quoted or when used as a variable assignment value or as a filename.
     However, when used as a command argument, _""""_$$$$_****_"""" is equivalent to
     _""""_$$$$_1111_d_$$$$_2222_d..._"""", where _d is the first character of the _IIII_FFFF_SSSS variable, whereas
     _""""_$$$$_@@@@_"""" is equivalent to _""""_$$$$_1111_""""_d_""""_$$$$_2222_""""_d_...._...._.... .  Inside grave quote marks (_````_````) _\\\\
     quotes the characters _\\\\, _````, and _$$$$.  If the grave quotes occur within
     double quotes, _\\\\ also quotes the character _"""".

     The special meaning of reserved words or aliases can be removed by
     quoting any character of the reserved word.  The recognition of function
     names or special command names listed below cannot be altered by quoting
     them.

   AAAArrrriiiitttthhhhmmmmeeeettttiiiicccc EEEEvvvvaaaalllluuuuaaaattttiiiioooonnnn
     An ability to perform integer arithmetic is provided with the special
     command _llll_eeee_tttt.  Evaluations are performed using _l_o_n_g arithmetic.  Constants
     are of the form [_b_a_s_e_####]_n where _b_a_s_e is a decimal number between two and
     thirty-six representing the arithmetic base and _n is a number in that
     base.  If _b_a_s_e_#### is omitted base 10 is used.





                                                                       PPPPaaaaggggeeee 11111111






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     An arithmetic expression uses the same syntax, precedence, and
     associativity of expression of the C language.  All the integral
     operators, other than _++++_++++, _----_----, _????_::::, and _,,,, are supported.  Variables can be
     referenced by name within an arithmetic expression without using the
     parameter substitution syntax.  When a variable is referenced, its value
     is evaluated as an arithmetic expression.

     An internal integer representation of a _v_a_r_i_a_b_l_e can be specified with
     the _----_iiii option of the _tttt_yyyy_pppp_eeee_ssss_eeee_tttt special command.  Arithmetic evaluation is
     performed on the value of each assignment to a variable with the _----_iiii
     attribute.  If you do not specify an arithmetic base, the first
     assignment to the variable determines the arithmetic base.  This base is
     used when parameter substitution occurs.

     Since many of the arithmetic operators require quoting, an alternative
     form of the _llll_eeee_tttt command is provided.  For any command which begins with a
     _((((_((((, all the characters until a matching _))))_)))) are treated as a quoted
     expression.  More precisely, _((((_((((..._))))_)))) is equivalent to _llll_eeee_tttt _""""..._"""".

   PPPPrrrroooommmmppppttttiiiinnnngggg
     When used interactively, the shell prompts with the parameter expanded
     value of _PPPP_SSSS_1111 before reading a command.  If at any time a newline is typed
     and further input is needed to complete a command, the secondary prompt
     (that is, the value of _PPPP_SSSS_2222) is issued.

   CCCCoooonnnnddddiiiittttiiiioooonnnnaaaallll EEEExxxxpppprrrreeeessssssssiiiioooonnnnssss
     A _c_o_n_d_i_t_i_o_n_a_l _e_x_p_r_e_s_s_i_o_n is used with the _[[[[_[[[[ compound command to test
     attributes of files and to compare strings.  Word splitting and filename
     generation are not performed on the words between _[[[[_[[[[ and _]]]]_]]]].  Each
     expression can be constructed from one or more of the following unary or
     binary expressions:

     _----_aaaa _f_i_l_e             True, if _f_i_l_e exists.
     _----_bbbb _f_i_l_e             True, if _f_i_l_e exists and is a block special file.
     _----_cccc _f_i_l_e             True, if _f_i_l_e exists and is a character special file.
     _----_dddd _f_i_l_e             True, if _f_i_l_e exists and is a directory.
     _----_eeee _f_i_l_e             Same as -a file.
     _----_ffff _f_i_l_e             True, if _f_i_l_e exists and is an ordinary file.
     _----_gggg _f_i_l_e             True, if _f_i_l_e exists and is has its setgid bit set.
     _----_kkkk _f_i_l_e             True, if _f_i_l_e exists and is has its sticky bit set.
     _----_nnnn _s_t_r_i_n_g           True, if length of _s_t_r_i_n_g is nonzero.
     _----_oooo _o_p_t_i_o_n           True, if option named _o_p_t_i_o_n is on.
     _----_pppp _f_i_l_e             True, if _f_i_l_e exists and is a fifo special file or a
                         pipe.
     _----_rrrr _f_i_l_e             True, if _f_i_l_e exists and is readable by current
                         process.
     _----_ssss _f_i_l_e             True, if _f_i_l_e exists and has size greater than zero.
     _----_tttt _f_i_l_d_e_s           True, if file descriptor number _f_i_l_d_e_s is open and
                         associated with a terminal device.
     _----_uuuu _f_i_l_e             True, if _f_i_l_e exists and is has its setuid bit set.





                                                                       PPPPaaaaggggeeee 11112222






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _----_wwww _f_i_l_e             True, if _f_i_l_e exists and is writable by current
                         process.
     _----_xxxx _f_i_l_e             True, if _f_i_l_e exists and is executable by current
                         process.  If _f_i_l_e exists and is a directory, the
                         current process has permission to search in the
                         directory.
     _----_zzzz _s_t_r_i_n_g           True, if length of _s_t_r_i_n_g is zero.
     _----_LLLL _f_i_l_e             True, if _f_i_l_e exists and is a symbolic link.
     _----_OOOO _f_i_l_e             True, if _f_i_l_e exists and is owned by the effective
                         user id of this process.
     _----_GGGG _f_i_l_e             True, if _f_i_l_e exists and its group matches the
                         effective group id of this process.
     _----_SSSS _f_i_l_e             True, if _f_i_l_e exists and is a socket.
     _f_i_l_e_1 _----_nnnn_tttt _f_i_l_e_2     True, if _f_i_l_e_1 exists and is newer than _f_i_l_e_2.
     _f_i_l_e_1 _----_oooo_tttt _f_i_l_e_2     True, if _f_i_l_e_1 exists and is older than _f_i_l_e_2.
     _f_i_l_e_1 _----_eeee_ffff _f_i_l_e_2     True, if _f_i_l_e_1 and _f_i_l_e_2 exist and refer to the same
                         file.
     _s_t_r_i_n_g _==== _p_a_t_t_e_r_n    True, if _s_t_r_i_n_g matches _p_a_t_t_e_r_n.
     _s_t_r_i_n_g _!!!!_==== _p_a_t_t_e_r_n   True, if _s_t_r_i_n_g does not match _p_a_t_t_e_r_n.
     _s_t_r_i_n_g_1 _<<<< _s_t_r_i_n_g_2   True, if _s_t_r_i_n_g_1 comes before _s_t_r_i_n_g_2 based on ASCII
                         value of their characters.
     _s_t_r_i_n_g_1 _>>>> _s_t_r_i_n_g_2   True, if _s_t_r_i_n_g_1 comes after _s_t_r_i_n_g_2 based on ASCII
                         value of their characters.
     _e_x_p_1 _----_eeee_qqqq _e_x_p_2       True, if _e_x_p_1 is equal to _e_x_p_2.
     _e_x_p_1 _----_nnnn_eeee _e_x_p_2       True, if _e_x_p_1 is not equal to _e_x_p_2.
     _e_x_p_1 _----_llll_tttt _e_x_p_2       True, if _e_x_p_1 is less than _e_x_p_2.
     _e_x_p_1 _----_gggg_tttt _e_x_p_2       True, if _e_x_p_1 is greater than _e_x_p_2.
     _e_x_p_1 _----_llll_eeee _e_x_p_2       True, if _e_x_p_1 is less than or equal to _e_x_p_2.
     _e_x_p_1 _----_gggg_eeee _e_x_p_2       True, if _e_x_p_1 is greater than or equal to _e_x_p_2.

     In each of the above expressions, if _f_i_l_e is of the form _////_dddd_eeee_vvvv_////_ffff_dddd_////_n, where
     _n is an integer, the test is applied to the open file whose descriptor
     number is _n.

     A compound expression can be constructed from these primitives by using
     any of the following, listed in decreasing order of precedence.

     _((((_e_x_p_r_e_s_s_i_o_n_))))                 True, if _e_x_p_r_e_s_s_i_o_n is true.  Used to group
                                  expressions.

     _!!!! _e_x_p_r_e_s_s_i_o_n                 True if _e_x_p_r_e_s_s_i_o_n is false.

     _e_x_p_r_e_s_s_i_o_n_1 _&&&&_&&&& _e_x_p_r_e_s_s_i_o_n_2   True, if _e_x_p_r_e_s_s_i_o_n_1 and _e_x_p_r_e_s_s_i_o_n_2 are
                                  both true.

     _e_x_p_r_e_s_s_i_o_n_1 _||||_|||| _e_x_p_r_e_s_s_i_o_n_2   True, if either _e_x_p_r_e_s_s_i_o_n_1 or _e_x_p_r_e_s_s_i_o_n_2
                                  is true.

   IIIInnnnppppuuuutttt////OOOOuuuuttttppppuuuutttt
     Before a command is executed, its input and output may be redirected
     using a special notation interpreted by the shell.  The following may
     appear anywhere in a simple-command or may precede or follow a _c_o_m_m_a_n_d



                                                                       PPPPaaaaggggeeee 11113333






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     and are not passed on to the invoked command.  Command and parameter
     substitution occurs before _w_o_r_d or _d_i_g_i_t is used except as noted below.
     Filename generation occurs only if the pattern matches a single file and
     blank interpretation is not performed.

     _<<<<_w_o_r_d       Use file _w_o_r_d as standard input (file descriptor 0).

     _>>>>_w_o_r_d       Use file _w_o_r_d as standard output (file descriptor 1).  If the
                 file does not exist it is created.  If the file exists, is a
                 regular file, and the _nnnn_oooo_cccc_llll_oooo_bbbb_bbbb_eeee_rrrr option is on, this causes an
                 error; otherwise, it is truncated to zero length.

     _>>>>_||||_w_o_r_d      Sames as _>>>>, except that it overrides the _nnnn_oooo_cccc_llll_oooo_bbbb_bbbb_eeee_rrrr option.

     _>>>>_>>>>_w_o_r_d      Use file _w_o_r_d as standard output.  If the file exists output
                 is appended to it (by first seeking to the end-of-file);
                 otherwise, the file is created.

     _<<<<_>>>>_w_o_r_d      Open file _w_o_r_d for reading and writing as standard input.

     _<<<<_<<<<[_----]_w_o_r_d   The shell input is read up to a line that is the same as
                 _w_o_r_d, or to an end-of-file.  No parameter substitution,
                 command substitution or filename generation is performed on
                 _w_o_r_d.  The resulting document, called a _h_e_r_e-_d_o_c_u_m_e_n_t,
                 becomes the standard input.  If any character of _w_o_r_d is
                 quoted, no interpretation is placed upon the characters of
                 the document; otherwise, parameter and command substitution
                 occurs, _\\\\_nnnn_eeee_wwww_llll_iiii_nnnn_eeee is ignored, and _\\\\ must be used to quote the
                 characters _\\\\, _$$$$, _````, and the first character of _w_o_r_d.  If _---- is
                 appended to _<<<<_<<<<, all leading tabs are stripped from _w_o_r_d and
                 from the document.

     _<<<<_&&&&_d_i_g_i_t     The standard input is duplicated from file descriptor _d_i_g_i_t
                 [see _dddd_uuuu_pppp(2)].  Similarly for the standard output using _>>>>_&&&&
                 _d_i_g_i_t.

     _<<<<_&&&&_----         The standard input is closed.  Similarly for the standard
                 output using _>>>>_&&&&_----.

     _<<<<_&&&&_pppp         The input from the co-process is moved to standard input.

     _>>>>_&&&&_pppp         The output to the co-process is moved to standard output.

     If one of the above is preceded by a digit, the file descriptor number
     referred to is that specified by the digit (instead of the default 0 or
     1).  For example,

          _...._...._.... _2222_>>>>_&&&&_1111

     means file descriptor 2 is to be opened for writing as a duplicate of
     file descriptor 1.




                                                                       PPPPaaaaggggeeee 11114444






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     The order in which redirections are specified is significant.  The shell
     evaluates each redirection in terms of the (_f_i_l_e _d_e_s_c_r_i_p_t_o_r, _f_i_l_e)
     association at the time of evaluation.  For example:

          _...._...._.... _1111_>>>>_f_n_a_m_e _2222_>>>>_&&&&_1111

     first associates file descriptor 1 with file _f_n_a_m_e.  It then associates
     file descriptor 2 with the file associated with file descriptor 1 (that
     is, _f_n_a_m_e).  If the order of redirections were reversed, file descriptor
     2 is associated with the terminal (assuming file descriptor 1 had been)
     and then file descriptor 1 is associated with file _f_n_a_m_e.

     If a command is followed by _&&&& and job control is not active, the default
     standard input for the command is the empty file _////_dddd_eeee_vvvv_////_nnnn_uuuu_llll_llll.  Otherwise,
     the environment for the execution of a command contains the file
     descriptors of the invoking shell as modified by input/output
     specifications.

   EEEEnnnnvvvviiiirrrroooonnnnmmmmeeeennnntttt
     The _e_n_v_i_r_o_n_m_e_n_t [see _eeee_nnnn_vvvv_iiii_rrrr_oooo_nnnn(5)] is a list of name-value pairs that is
     passed to an executed program in the same way as a normal argument list.
     The names must be _i_d_e_n_t_i_f_i_e_r_s and the values are character strings.  The
     shell interacts with the environment in several ways.  On invocation, the
     shell scans the environment and creates a variable for each name found,
     giving it the corresponding value and marking it _e_x_p_o_r_t . Executed
     commands inherit the environment.  If the user modifies the values of
     these variables or creates new ones, using the _eeee_xxxx_pppp_oooo_rrrr_tttt or _tttt_yyyy_pppp_eeee_ssss_eeee_tttt _----_xxxx
     commands they become part of the environment.  The environment seen by
     any executed command is thus composed of any name-value pairs originally
     inherited by the shell, whose values may be modified by the current
     shell, plus any additions which must be noted in _eeee_xxxx_pppp_oooo_rrrr_tttt or _tttt_yyyy_pppp_eeee_ssss_eeee_tttt _----_xxxx
     commands.

     The environment for any _s_i_m_p_l_e-_c_o_m_m_a_n_d or function may be augmented by
     prefixing it with one or more variable assignments.  A variable
     assignment argument is a word of the form _i_d_e_n_t_i_f_i_e_r=_v_a_l_u_e.  Thus, the
     commands:

          _TTTT_EEEE_RRRR_MMMM_====_4444_5555_0000 _c_m_d _a_r_g_s
          _((((_eeee_xxxx_pppp_oooo_rrrr_tttt _TTTT_EEEE_RRRR_MMMM_;;;; _TTTT_EEEE_RRRR_MMMM_====_4444_5555_0000_;;;; _c_m_d _a_r_g_s_))))

     are equivalent (as far as the above execution of _c_m_d is concerned except
     for commands listed with one or two asterisks, * or **, in the SSSSppppeeeecccciiiiaaaallll
     CCCCoooommmmmmmmaaaannnnddddssss section).

     If the _----_kkkk flag is set, _a_l_l variable assignment arguments are placed in
     the environment, even if they occur after the command name.  The
     following first prints _aaaa_====_bbbb _cccc and then _cccc_::::

          _eeee_cccc_hhhh_oooo _aaaa_====_bbbb _cccc
          _ssss_eeee_tttt _----_kkkk
          _eeee_cccc_hhhh_oooo _aaaa_====_bbbb _cccc



                                                                       PPPPaaaaggggeeee 11115555






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     This feature is intended for use with scripts written for early versions
     of the shell and its use in new scripts is strongly discouraged.  It is
     likely to disappear someday.

   FFFFuuuunnnnccccttttiiiioooonnnnssss
     The _ffff_uuuu_nnnn_cccc_tttt_iiii_oooo_nnnn reserved word, described in the Commands section above, is
     used to define shell functions.  Shell functions are read in and stored
     internally.  Alias names are resolved when the function is read.
     Functions are executed like commands with the arguments passed as
     positional parameters (see Execution below).  Within a function, the
     special positional parameter $0 may be the name of the invoking program
     or the name of the function, depending on how the shell is invoked.  (See
     the _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document)

     Functions execute in the same process as the caller and share all files
     and present working directory with the caller.  Traps caught by the
     caller are reset to their default action inside the function.  A trap
     condition that is not caught or ignored by the function causes the
     function to terminate and the condition to be passed on to the caller.  A
     trap on _EEEE_XXXX_IIII_TTTT set inside a function is executed after the function
     completes in the environment of the caller.  Ordinarily, variables are
     shared between the calling program and the function.  However, the
     _tttt_yyyy_pppp_eeee_ssss_eeee_tttt special command used within a function defines local variables
     whose scope includes the current function and all functions it calls.

     The special command _rrrr_eeee_tttt_uuuu_rrrr_nnnn is used to return from function calls.  Errors
     within functions return control to the caller.

     Function identifiers can be listed with the _----_ffff or _++++_ffff option of the
     _tttt_yyyy_pppp_eeee_ssss_eeee_tttt special command.  The text of functions may also be listed with
     _----_ffff.  Function can be undefined with the _----_ffff option of the _uuuu_nnnn_ssss_eeee_tttt special
     command.

     Ordinarily, functions are unset when the shell executes a shell script.
     The _----_xxxx_ffff option of the _tttt_yyyy_pppp_eeee_ssss_eeee_tttt command allows a function to be exported to
     scripts that are executed without a separate invocation of the shell.
     Functions that need to be defined across separate invocations of the
     shell should be specified in the _EEEE_NNNN_VVVV file with the _----_xxxx_ffff option of _tttt_yyyy_pppp_eeee_ssss_eeee_tttt.

   JJJJoooobbbbssss
     If the _mmmm_oooo_nnnn_iiii_tttt_oooo_rrrr option of the _ssss_eeee_tttt command is turned on, an interactive
     shell associates a _j_o_b with each pipeline.  It keeps a table of current
     jobs, printed by the _jjjj_oooo_bbbb_ssss command, and assigns them small integer
     numbers.  The max number of jobs is defined by the systune value 'maxup'.
     This is determined at shell invocation. When a job is started
     asynchronously with _&&&&, the shell prints a line which looks like:

          [1] 1234

     indicating that the job which was started asynchronously was job number 1
     and had one (top-level) process, whose process id was 1234.




                                                                       PPPPaaaaggggeeee 11116666






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     If you are running a job and wish to do something else you may hit the
     key _^^^^_ZZZZ (CTRL-z) which sends a STOP signal to the current job.  The shell
     normally indicates that the job has been `Stopped', and prints another
     prompt.  You can manipulate the state of this job, putting it in the
     background with the _bbbb_gggg command or run some other commands and eventually
     bring the job back into the foreground with the foreground command _ffff_gggg.  A
     _^^^^_ZZZZ takes effect immediately and is like an interrupt in that pending
     output and unread input are discarded when it is typed.

     A job being run in the background stops if it tries to read from the
     terminal.  Background jobs are normally allowed to produce output, but
     this can be disabled by giving the command ``stty tostop''.  If you set
     this tty option, background jobs stop when they try to produce output
     like they do when they try to read input.

     There are several ways to refer to jobs in the shell.  A job can be
     referred to by the process id of any process of the job or by one of the
     following:

     _%%%%_n_u_m_b_e_r    The job with the given number.

     _%%%%_s_t_r_i_n_g    Any job whose command line begins with _s_t_r_i_n_g.

     _%%%%_????_s_t_r_i_n_g   Any job whose command line contains _s_t_r_i_n_g.

     _%%%%_%%%%         Current job.

     _%%%%_++++         Equivalent to _%%%%_%%%%.

     _%%%%_----         Previous job.

     This shell learns immediately whenever a process changes state.  It
     normally informs you whenever a job becomes blocked so that no further
     progress is possible, but only just before it prints a prompt.  This is
     done so that it does not otherwise disturb your work.

     When the monitor mode is on, each background job that completes triggers
     any trap set for _CCCC_HHHH_LLLL_DDDD.

     When you try to leave the shell while jobs are running or stopped, you
     are be warned that `You have stopped(running) jobs.'  You may use the
     _jjjj_oooo_bbbb_ssss command to see what they are.  If you do this or immediately try to
     exit again, the shell does not warn you a second time, and the stopped
     jobs are terminated.

   SSSSiiiiggggnnnnaaaallllssss
     When a command is run in the background (that it, when it is followed by
     _&&&&) and the job _mmmm_oooo_nnnn_iiii_tttt_oooo_rrrr option is active, the command does not receive
     INTERRUPT or QUIT signals.  When a command is run in the background (that
     it, when it is followed by _&&&&) and the job _mmmm_oooo_nnnn_iiii_tttt_oooo_rrrr option is not active,
     the command receives INTERRUPT or QUIT signals but ignores them.
     Otherwise, signals have the values inherited by the shell from its parent



                                                                       PPPPaaaaggggeeee 11117777






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     (but see also the _tttt_rrrr_aaaa_pppp command below).

   EEEExxxxeeeeccccuuuuttttiiiioooonnnn
     Each time a command is executed, the above substitutions are carried out.
     If the command name matches one of the special commands listed below, it
     is executed within the current shell process.  Next, the command name is
     checked to see if it matches one of the user defined functions.  If it
     does, the positional parameters are saved and reset to the arguments of
     the _f_u_n_c_t_i_o_n call.  When the _f_u_n_c_t_i_o_n completes or issues a _rrrr_eeee_tttt_uuuu_rrrr_nnnn, the
     positional parameter list is restored and any trap set on _EEEE_XXXX_IIII_TTTT within the
     function is executed.  The value of a _f_u_n_c_t_i_o_n is the value of the last
     command executed.  A function is also executed in the current shell
     process.  If a command name is not a _s_p_e_c_i_a_l _c_o_m_m_a_n_d or a user defined
     _f_u_n_c_t_i_o_n, a process is created and an attempt is made to execute the
     command via _eeee_xxxx_eeee_cccc(2).

     The shell variable _PPPP_AAAA_TTTT_HHHH defines the search path for the directory
     containing the command.  Alternative directory names are separated by a
     colon (_::::).  The default path is _////_uuuu_ssss_rrrr_////_bbbb_iiii_nnnn_::::  (specifying _////_uuuu_ssss_rrrr_////_bbbb_iiii_nnnn and the
     current directory in that order).  The current directory can be specified
     by two or more adjacent colons, or by a colon at the beginning or end of
     the path list.  If the command name contains a _//// the search path is not
     used.  Otherwise, each directory in the path is searched for an
     executable file.  If the file has execute permission but is not a
     directory or an _aaaa_...._oooo_uuuu_tttt file, it is assumed to be a file containing shell
     commands.  A sub-shell is spawned to read it.  All non-exported aliases,
     functions, and variables, are removed in this case.  A parenthesized
     command is executed in a sub-shell without removing non-exported
     quantities.

   CCCCoooommmmmmmmaaaannnndddd RRRReeee----eeeennnnttttrrrryyyy
     The text of the last _HHHH_IIII_SSSS_TTTT_SSSS_IIII_ZZZZ_EEEE (default 128) commands entered from a
     terminal device is saved in a _h_i_s_t_o_r_y file.  The file _$$$$_HHHH_OOOO_MMMM_EEEE_////_...._ssss_hhhh______hhhh_iiii_ssss_tttt_oooo_rrrr_yyyy
     is used if the file denoted by the _HHHH_IIII_SSSS_TTTT_FFFF_IIII_LLLL_EEEE variable is not set or is not
     writable.  A shell can access the commands of all _i_n_t_e_r_a_c_t_i_v_e shells
     which use the same named _HHHH_IIII_SSSS_TTTT_FFFF_IIII_LLLL_EEEE.  The special command _ffff_cccc is used to
     list or edit a portion of this file.  The portion of the file to be
     edited or listed can be selected by number or by giving the first
     character or characters of the command.  A single command or range of
     commands can be specified.  If you do not specify an editor program as an
     argument to _ffff_cccc the value of the variable _FFFF_CCCC_EEEE_DDDD_IIII_TTTT is used.  If _FFFF_CCCC_EEEE_DDDD_IIII_TTTT is
     not defined _////_uuuu_ssss_rrrr_////_bbbb_iiii_nnnn_////_eeee_dddd is used.  The edited command(s) is printed and
     re-executed upon leaving the editor.  The editor name _---- is used to skip
     the editing phase and to re-execute the command.  In this case a
     substitution variable of the form _o_l_d_====_n_e_w can be used to modify the
     command before execution.  For example, if _rrrr is aliased to _''''_ffff_cccc _----_eeee _----_'''',
     typing `_rrrr _bbbb_aaaa_dddd_====_gggg_oooo_oooo_dddd _cccc' re-executes the most recent command that starts
     with the letter _cccc, replacing the first occurrence of the string _bbbb_aaaa_dddd with
     the string _gggg_oooo_oooo_dddd.






                                                                       PPPPaaaaggggeeee 11118888






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



   IIIInnnnlllliiiinnnneeee EEEEddddiiiittttiiiinnnngggg OOOOppppttttiiiioooonnnn
     Normally, each command line entered from a terminal device is simply
     typed followed by a newline (`RETURN' or `LINE FEED').  If either the
     _eeee_mmmm_aaaa_cccc_ssss, or _vvvv_iiii option is active, the user can edit the command line.  To be
     in either of these edit modes _ssss_eeee_tttt the corresponding option.  An editing
     option is automatically selected each time the _VVVV_IIII_SSSS_UUUU_AAAA_LLLL or _EEEE_DDDD_IIII_TTTT_OOOO_RRRR variable
     is assigned a value ending in either of these option names.

     The editing features require that the user's terminal accept `RETURN' as
     carriage return without line feed and that a space (` ') must overwrite
     the current character on the screen.

     The editing modes implement a concept where the user is looking through a
     window at the current line.  The window width is the value of _CCCC_OOOO_LLLL_UUUU_MMMM_NNNN_SSSS if
     it is defined, otherwise 80.  If the line is longer than the window width
     minus two, a mark is displayed at the end of the window to notify the
     user.  As the cursor moves and reaches the window boundaries, the window
     is centered about the cursor.  The mark is a _>>>> (<_,,,, _****) if the line extends
     on the right (left, both) side(s) of the window.

     The search commands in each edit mode provide access to the history file.
     Only strings are matched, not patterns, although a leading _^^^^ in the
     string restricts the match to begin at the first character in the line.

   EEEEmmmmaaaaccccssss EEEEddddiiiittttiiiinnnngggg MMMMooooddddeeee
     This mode is entered by enabling either the _e_m_a_c_s or _g_m_a_c_s option.  The
     only difference between these two modes is the way they handle _^^^^_TTTT.  To
     edit, the user moves the cursor to the point needing correction and then
     inserts or deletes characters or words as needed.  All the editing
     commands are control characters or escape sequences.  The notation for
     control characters is caret ( _^^^^ ) followed by the character.  For
     example, _^^^^_FFFF is the notation for CTRL-_ffff.  This is entered by depressing
     `f' while holding down the `CTRL' (control) key.  (The notation _^^^^_????
     indicates the DEL (delete) key.)

     The notation for escape sequences is _MMMM_---- followed by a character.  For
     example, _MMMM_----_ffff (pronounced Meta f) is entered by depressing ESC (ascii
     _\\\\_0000_3333_3333) followed by `f'.  (_MMMM_----_FFFF would be the notation for ESC followed by
     `SHIFT' (capital) `F'.)

     All edit commands operate from any place on the line (not just at the
     beginning).  Neither the "RETURN" nor the "LINE FEED" key is entered
     after edit commands except when noted.

     _^^^^_FFFF        Move cursor forward (right) one character.
     _MMMM_----_ffff       Move cursor forward one word.  (The emacs editor's idea of a
               word is a string of characters consisting of only letters,
               digits and underscores.)
     _^^^^_BBBB        Move cursor backward (left) one character.
     _MMMM_----_bbbb       Move cursor backward one word.





                                                                       PPPPaaaaggggeeee 11119999






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _^^^^_AAAA        Move cursor to start of line.
     _^^^^_EEEE        Move cursor to end of line.
     _^^^^_]]]]_c_h_a_r    Move cursor forward to character _c_h_a_r on current line.
     _MMMM_----_^^^^_]]]]_c_h_a_r  Move cursor back to character _c_h_a_r on current line.
     _^^^^_XXXX_^^^^_XXXX      Interchange the cursor and mark.
     _e_r_a_s_e     (User defined erase character as defined by the _ssss_tttt_tttt_yyyy(1)
               command, usually _^^^^_HHHH or _####.)  Delete previous character.
     _^^^^_DDDD        Delete current character.
     _MMMM_----_dddd       Delete current word.
     _MMMM_----_^^^^_HHHH      (Meta-backspace) Delete previous word.
     _MMMM_----_hhhh       Delete previous word.
     _MMMM_----_^^^^_????      (Meta-DEL) Delete previous word (if your interrupt character is
               _^^^^_????  (DEL, the default) then this command will not work).
     _^^^^_TTTT        Transpose current character with next character in _e_m_a_c_s mode.
               Transpose two previous characters in _g_m_a_c_s mode.
     _^^^^_CCCC        Capitalize current character.
     _MMMM_----_cccc       Capitalize current word.
     _MMMM_----_llll       Change the current word to lower case.
     _^^^^_KKKK        Delete from the cursor to the end of the line.  If preceded by
               a numerical parameter whose value is less than the current
               cursor position, then delete from given position up to the
               cursor.  If preceded by a numerical parameter whose value is
               greater than the current cursor position, then delete from
               cursor up to given cursor position.
     _^^^^_WWWW        Kill from the cursor to the mark.
     _MMMM_----_pppp       Push the region from the cursor to the mark on the stack.
     _kkkk_iiii_llll_llll      (User defined kill character as defined by the stty command,
               usually _^^^^_GGGG or _@@@@.)  Kill the entire current line.  If two _kkkk_iiii_llll_llll
               characters are entered in succession, all kill characters from
               then on cause a line feed (useful when using paper terminals).
     _^^^^_YYYY        Restore last item removed from line. (Yank item back to the
               line.)
     _^^^^_LLLL        Line feed and print current line.
     _^^^^_@@@@        (Null character) Set mark.
     _MMMM_----_ssss_pppp_aaaa_cccc_eeee   (Meta space) Set mark.
     _^^^^_JJJJ        (New line) Execute the current line.
     _^^^^_MMMM        (Return) Execute the current line.
     _e_o_f       End-of-file character, normally _^^^^_DDDD, is processed as an End-of-
               file only if the current line is null.
     _^^^^_PPPP        Fetch previous command.  Each time _^^^^_PPPP is entered the previous
               command back in time is accessed.  Moves back one line when not
               on the first line of a multi-line command.
     _MMMM_----_<<<<       Fetch the least recent (oldest) history line.
     _MMMM_----_>>>>       Fetch the most recent (youngest) history line.
     _^^^^_NNNN        Fetch next command line.  Each time _^^^^_NNNN is entered the next
               command line forward in time is accessed.
     _^^^^_RRRR_s_t_r_i_n_g  Reverse search history for a previous command line containing
               _s_t_r_i_n_g.  If a parameter of zero is given, the search is
               forward.  _S_t_r_i_n_g is terminated by a "RETURN" or "NEW LINE".  If
               string is preceded by a _^^^^, the matched line must begin with
               _s_t_r_i_n_g.  If _s_t_r_i_n_g is omitted, then the next command line
               containing the most recent _s_t_r_i_n_g is accessed.  In this case a



                                                                       PPPPaaaaggggeeee 22220000






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



               parameter of zero reverses the direction of the search.
     _^^^^_OOOO        Operate - Execute the current line and fetch the next line
               relative to current line from the history file.
     _MMMM_----_d_i_g_i_t_s  (Escape) Define numeric parameter, the digits are taken as a
               parameter to the next command.  The commands that accept a
               parameter are _^^^^_FFFF, _^^^^_BBBB, _e_r_a_s_e, _^^^^_CCCC, _^^^^_DDDD, _^^^^_KKKK, _^^^^_RRRR, _^^^^_PPPP, _^^^^_NNNN, _^^^^_]]]], _MMMM_----_....,
               _MMMM_----_^^^^_]]]], _MMMM_----_____, _MMMM_----_bbbb, _MMMM_----_cccc, _MMMM_----_dddd, _MMMM_----_ffff, _MMMM_----_hhhh _MMMM_----_llll and _MMMM_----_^^^^_HHHH.
     _MMMM_----_l_e_t_t_e_r  Soft-key - Your alias list is searched for an alias by the name
               ______l_e_t_t_e_r and if an alias of this name is defined, its value will
               be inserted on the input queue.  The _l_e_t_t_e_r must not be one of
               the above meta-functions.  _MMMM_----_]]]]_l_e_t_t_e_r Soft-key - Your alias list
               is searched for an alias by the name ___________l_e_t_t_e_r and if an alias
               of this name is defined, its value will be inserted on the
               input queue.  The can be used to program functions keys on many
               terminals.
     _MMMM_----_....       The last word of the previous command is inserted on the line.
               If preceded by a numeric parameter, the value of this parameter
               determines which word to insert rather than the last word.
     _MMMM_----_____       Same as _MMMM_----_.....
     _MMMM_----_****       Attempt file name generation on the current word.  An asterisk
               is appended if the word doesn't match any file or contain any
               special pattern characters.
     _MMMM_----_EEEE_SSSS_CCCC     File name completion.  Replaces the current word with the
               longest common prefix of all filenames matching the current
               word with an asterisk appended.  If the match is unique, a _//// is
               appended if the file is a directory and a space is appended if
               the file is not a directory.
     _MMMM_----_====       List files matching current word pattern if an asterisk were
               appended.
     _^^^^_UUUU        Multiply parameter of next command by 4.
     _\\\\         Escape next character.  Editing characters, the user's erase,
               kill and interrupt (normally _^^^^_????)  characters may be entered in
               a command line or in a search string if preceded by a _\\\\.  The _\\\\
               removes the next character's editing features (if any).
     _^^^^_VVVV        Display version of the shell.
     _MMMM_----_####       Insert a _#### at the beginning of the line and execute it.  This
               causes a comment to be inserted in the history file.

   vvvviiii EEEEddddiiiittttiiiinnnngggg MMMMooooddddeeee
     There are two typing modes.  Initially, when you enter a command you are
     in the _i_n_p_u_t mode.  To edit, the user enters _c_o_n_t_r_o_l mode by typing ESC
     (_\\\\_0000_3333_3333), moves the cursor to the point needing correction, and inserts or
     deletes characters or words as needed.  Most control commands accept an
     optional repeat _c_o_u_n_t prior to the command.

     When in _vvvv_iiii mode on most systems, canonical processing is initially
     enabled and the command is echoed again if the speed is 1200 baud or
     greater and it contains any control characters or less than one second
     has elapsed since the prompt was printed.  The ESC character terminates
     canonical processing for the remainder of the command and the user can
     modify the command line.  This scheme has the advantages of canonical
     processing with the type-ahead echoing of raw mode.



                                                                       PPPPaaaaggggeeee 22221111






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     If the option _vvvv_iiii_rrrr_aaaa_wwww is also set, the terminal always has canonical
     processing disabled.

   IIIInnnnppppuuuutttt EEEEddddiiiitttt CCCCoooommmmmmmmaaaannnnddddssss
     By default the editor is in input mode.

     _e_r_a_s_e   (User defined erase character as defined by the stty command,
             usually _^^^^_HHHH or _####.)  Delete previous character.

     _^^^^_WWWW      Delete the previous blank separated word.

     _^^^^_DDDD      Terminate the shell.

     _^^^^_VVVV      Escape next character.  Editing characters, the user's erase or
             kill characters may be entered in a command line or in a search
             string if preceded by a _^^^^_VVVV.  The _^^^^_VVVV removes the next character's
             editing features (if any).

     _\\\\       Escape the next _e_r_a_s_e or _kkkk_iiii_llll_llll character.

   MMMMoooottttiiiioooonnnn EEEEddddiiiitttt CCCCoooommmmmmmmaaaannnnddddssss
     These commands move the cursor.

     [_c_o_u_n_t]_llll    Cursor forward (right) one character.

     [_c_o_u_n_t]_wwww    Cursor forward one alpha-numeric word.

     [_c_o_u_n_t]_WWWW    Cursor to the beginning of the next word that follows a
                 blank.

     [_c_o_u_n_t]_eeee    Cursor to end of word.

     [_c_o_u_n_t]_EEEE    Cursor to end of the current blank delimited word.

     [_c_o_u_n_t]_hhhh    Cursor backward (left) one character.

     [_c_o_u_n_t]_bbbb    Cursor backward one word.

     [_c_o_u_n_t]_BBBB    Cursor to preceding blank separated word.

     [_c_o_u_n_t]_||||    Cursor to column _c_o_u_n_t.

     [_c_o_u_n_t]_ffff_c   Find the next character _c in the current line.

     [_c_o_u_n_t]_FFFF_c   Find the previous character _c in the current line.

     [_c_o_u_n_t]_tttt_c   Equivalent to _ffff followed by _hhhh.

     [_c_o_u_n_t]_TTTT_c   Equivalent to _FFFF followed by _llll.






                                                                       PPPPaaaaggggeeee 22222222






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     [_c_o_u_n_t]_;;;;    Repeats _c_o_u_n_t times, the last single character find command,
                 _ffff, _FFFF, _tttt, or _TTTT.

     [_c_o_u_n_t]_,,,,    Reverses the last single character find command _c_o_u_n_t times.

     _0000           Cursor to start of line.

     _^^^^           Cursor to first non-blank character in line.

     _$$$$           Cursor to end of line.

   SSSSeeeeaaaarrrrcccchhhh EEEEddddiiiitttt CCCCoooommmmmmmmaaaannnnddddssss
     These commands access your command history.

     [_c_o_u_n_t]_kkkk    Fetch previous command.  Each time _kkkk is entered the previous
                 command back in time is accessed.

     [_c_o_u_n_t]_----    Equivalent to _kkkk.

     [_c_o_u_n_t]_jjjj    Fetch next command.  Each time _jjjj is entered the next command
                 forward in time is accessed.

     [_c_o_u_n_t]_++++    Equivalent to _jjjj.

     [_c_o_u_n_t]_GGGG    The command number _c_o_u_n_t is fetched.  The default is the
                 least recent history command.

     _////_s_t_r_i_n_g     Search backward through history for a previous command
                 containing _s_t_r_i_n_g.  _S_t_r_i_n_g is terminated by a "RETURN" or
                 "NEW LINE".  If string is preceded by a _^^^^, the matched line
                 must begin with _s_t_r_i_n_g.  If _s_t_r_i_n_g is null the previous
                 string is used.

     _????_s_t_r_i_n_g     Same as _//// except that search is in the forward direction.

     _nnnn           Search for next match of the last pattern to _//// or _????
                 commands.

     _NNNN           Search for next match of the last pattern to _//// or _????, but in
                 reverse direction.  Search history for the _s_t_r_i_n_g entered by
                 the previous _//// command.

   TTTTeeeexxxxtttt MMMMooooddddiiiiffffiiiiccccaaaattttiiiioooonnnn EEEEddddiiiitttt CCCCoooommmmmmmmaaaannnnddddssss
     These commands modify the line.

     _aaaa                Enter input mode and enter text after the current
                      character.

     _AAAA                Append text to the end of the line.  Equivalent to _$$$$_aaaa.






                                                                       PPPPaaaaggggeeee 22223333






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     [_c_o_u_n_t]_cccc_m_o_t_i_o_n
     _cccc[_c_o_u_n_t]_m_o_t_i_o_n   Delete current character through the character that
                      _m_o_t_i_o_n would move the cursor to and enter input mode.
                      If _m_o_t_i_o_n is _cccc, the entire line is deleted and input
                      mode entered.

     _CCCC                Delete the current character through the end of line and
                      enter input mode.  Equivalent to _cccc_$$$$.

     _SSSS                Equivalent to _cccc_cccc.

     _DDDD                Delete the current character through the end of line.
                      Equivalent to _dddd_$$$$.

     [_c_o_u_n_t]_dddd_m_o_t_i_o_n
     _dddd[_c_o_u_n_t]_m_o_t_i_o_n   Delete current character through the character that
                      _m_o_t_i_o_n would move to.  If _m_o_t_i_o_n is _dddd, the entire line
                      is deleted.

     _iiii                Enter input mode and insert text before the current
                      character.

     _IIII                Insert text before the beginning of the line.
                      Equivalent to _0000_iiii.

     [_c_o_u_n_t]_PPPP         Place the previous text modification before the cursor.

     [_c_o_u_n_t]_pppp         Place the previous text modification after the cursor.

     _RRRR                Enter input mode and replace characters on the screen
                      with characters you type overlay fashion.

     [_c_o_u_n_t]_rrrr_c        Replace the _c_o_u_n_t character(s) starting at the current
                      cursor position with _c, and advance the cursor.

     [_c_o_u_n_t]_xxxx         Delete current character.

     [_c_o_u_n_t]_XXXX         Delete preceding character.

     [_c_o_u_n_t]_....         Repeat the previous text modification command.

     [_c_o_u_n_t]_~~~~         Invert the case of the _c_o_u_n_t character(s) starting at
                      the current cursor position and advance the cursor.

     [_c_o_u_n_t]_____         Causes the _c_o_u_n_t word of the previous command to be
                      appended and input mode entered.  The last word is used
                      if _c_o_u_n_t is omitted.

     _****                Causes an _**** to be appended to the current word and
                      filename generation attempted.  If no match is found, it
                      rings the bell.  Otherwise, the word is replaced by the
                      matching pattern and input mode is entered.



                                                                       PPPPaaaaggggeeee 22224444






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _\\\\                Filename completion.  Replaces the current word with the
                      longest common prefix of all filenames matching the
                      current word with an asterisk appended.  If the match is
                      unique, a _//// is appended if the file is a directory and a
                      space is appended if the file is not a directory.

   OOOOtttthhhheeeerrrr EEEEddddiiiitttt CCCCoooommmmmmmmaaaannnnddddssss
     Miscellaneous commands.

     [_c_o_u_n_t]_yyyy_m_o_t_i_o_n
     _yyyy[_c_o_u_n_t]_m_o_t_i_o_n   Yank current character through character that _m_o_t_i_o_n
                      would move the cursor to and puts them into the delete
                      buffer.  The text and cursor are unchanged.

     _YYYY                Yanks from current position to end of line.  Equivalent
                      to _yyyy_$$$$.

     _uuuu                Undo the last text modifying command.

     _UUUU                Undo all the text modifying commands performed on the
                      line.

     [_c_o_u_n_t]_vvvv         Returns the command _ffff_cccc _----_eeee _$$$$_{{{{_VVVV_IIII_SSSS_UUUU_AAAA_LLLL_::::_----_$$$$_{{{{_EEEE_DDDD_IIII_TTTT_OOOO_RRRR_::::_----_vvvv_iiii_}}}}_}}}} _c_o_u_n_t
                      in the input buffer.  If _c_o_u_n_t is omitted, the current
                      line is used.

     _^^^^_LLLL               Line feed and print current line.  Has effect only in
                      control mode.

     _^^^^_JJJJ               (New line) Execute the current line, regardless of mode.

     _^^^^_MMMM               (Return) Execute the current line, regardless of mode.

     _####                Sends the line after inserting a _#### in front of the line.
                      Useful for causing the current line to be inserted in
                      the history without being executed.

     _====                List the filenames that match the current word if an
                      asterisk were appended it.

     _@@@@_l_e_t_t_e_r          Your alias list is searched for an alias by the name
                      ______l_e_t_t_e_r and if an alias of this name is defined, its
                      value is inserted on the input queue for processing.

   SSSSppppeeeecccciiiiaaaallll CCCCoooommmmmmmmaaaannnnddddssss
     The following simple-commands are executed in the shell process.
     Input/output redirection is permitted.  Unless otherwise indicated, the
     output is written on file descriptor 1 and the exit status, when there is
     no syntax error, is zero.  Commands that are followed by one or two
     asterisks, * or **, are treated specially in the following ways:





                                                                       PPPPaaaaggggeeee 22225555






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     1.   Variable assignment lists preceding the command remain in effect
          when the command completes.

     2.   I/O redirections are processed after variable assignments.

     3.   Errors cause a script that contains them to abort.

     4.   Words, following a command followed by ** that are in the format of
          a variable assignment, are expanded with the same rules as a
          variable assignment.  This means that tilde substitution is
          performed after the _==== sign and word splitting and filename
          generation are not performed.

     _:::: [ _a_r_g ... ]     *
          The command only expands parameters.

     _.... _f_i_l_e [ _a_r_g ... ]     *
          Read the complete _f_i_l_e and execute the commands.  The commands are
          executed in the current shell environment.  The search path
          specified by _PPPP_AAAA_TTTT_HHHH is used to find the directory containing _f_i_l_e.  If
          any arguments _a_r_g are given, they become the positional parameters.
          Otherwise the positional parameters are unchanged.  The exit status
          is the exit status of the last command executed.

     _aaaa_llll_iiii_aaaa_ssss [ _----_tttt_xxxx ] [ _n_a_m_e[_====_v_a_l_u_e ] ] ...     **
          _A_l_i_a_s with no arguments prints the list of aliases in the form
          _n_a_m_e=_v_a_l_u_e on standard output.  An _a_l_i_a_s is defined for each name
          whose _v_a_l_u_e is given.  A trailing space in _v_a_l_u_e causes the next
          word to be checked for alias substitution.  The _----_tttt flag is used to
          set and list tracked aliases.  The value of a tracked alias is the
          full pathname corresponding to the given _n_a_m_e.  The value becomes
          undefined when the value of _PPPP_AAAA_TTTT_HHHH is reset but the aliases remain
          tracked.  Without the _----_tttt flag, for each _n_a_m_e in the argument list
          for which no _v_a_l_u_e is given, the name and value of the alias is
          printed.  The _----_xxxx flag is used to set or print exported aliases.  An
          exported alias is defined for scripts invoked by name.  The exit
          status is nonzero if a _n_a_m_e is given, but no value, for which no
          alias has been defined.

     _bbbb_gggg [ _j_o_b... ]
          This command is only on systems that support job control.  Puts each
          specified _j_o_b into the background.  The current job is put in the
          background if _j_o_b is not specified.  See JJJJoooobbbbssss for a description of
          the format of _j_o_b.

     _bbbb_rrrr_eeee_aaaa_kkkk [ _n ]     *
          Exit from the enclosing _ffff_oooo_rrrr, _wwww_hhhh_iiii_llll_eeee, _uuuu_nnnn_tttt_iiii_llll or _ssss_eeee_llll_eeee_cccc_tttt loop, if any.
          If _n is specified, break _n levels.

     _cccc_oooo_mmmm_mmmm_aaaa_nnnn_dddd [ _----_pppp ] _c_o_m_m_a_n_d__n_a_m_e [ _a_r_g_u_m_e_n_t ... ]





                                                                       PPPPaaaaggggeeee 22226666






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _cccc_oooo_mmmm_mmmm_aaaa_nnnn_dddd [ _----_vvvv _|||| _----_VVVV ] _c_o_m_m_a_n_d__n_a_m_e
          The _c_o_m_m_a_n_d utility causes the shell to treat the arguments as a
          simple command, suppressing the shell function lookup.  If the
          _c_o_m_m_a_n_d__n_a_m_e is the same as the name of one of the special builtin
          utilities, the special properties in the enumerated list at the
          beginning of SSSSppppeeeecccciiiiaaaallll CCCCoooommmmmmmmaaaannnnddddssss section do not occur.  In every other
          respect, if _c_o_m_m_a_n_d__n_a_m_e is not the name of a function, the effect
          of _c_o_m_m_a_n_d are the same as omitting _c_o_m_m_a_n_d.

          The _----_pppp option performs the search using a default value for _P_A_T_H
          that is guaranteed to find all of the standard utilities.

          The _----_vvvv option writes a string to standard output that indicates the
          pathname or command that will be used by the shell, in the current
          execution environment, to invoke _c_o_m_m_a_n_d__n_a_m_e.

          The _----_VVVV option writes a string to standard output that indicates how
          the name given in the _c_o_m_m_a_n_d__n_a_m_e operand is interpreted by the
          shell in the current shell execution environment.  It indicates in
          which of the following categories _c_o_m_m_a_n_d__n_a_m_e falls and include the
          information stated:

          Utilities, regular builtin utilities, and any implementation-
          provided functions that are found using the _P_A_T_H variable are
          identified as such and include the absolute pathname in the string.

          Other shell functions are identified as functions.

          Aliases are identified as aliases and their definitions are included
          in the string.

          Special builtin utilities are identified as special builtin
          utilities.

          Regular builtin utilities not associated with a _P_A_T_H search are
          identified as regular builtin utilities.

          Shell reserved words are identified as reserved words.

     _cccc_oooo_nnnn_tttt_iiii_nnnn_uuuu_eeee [ _n ]     *
          Resume the next iteration of the enclosing _ffff_oooo_rrrr, _wwww_hhhh_iiii_llll_eeee, _uuuu_nnnn_tttt_iiii_llll or
          _ssss_eeee_llll_eeee_cccc_tttt loop.  If _n is specified, resume at the _n-th enclosing loop.

     _cccc_dddd _[[[[ _----_LLLL_PPPP _]]]]   _a_r_g
     _cccc_dddd _[[[[ _----_LLLL_PPPP _]]]]  _o_l_d _n_e_w
          This command can be in either of two forms.  In the first form it
          changes the current directory to _a_r_g.  If _a_r_g is _---- the directory is
          changed to the previous directory.  The shell variable _HHHH_OOOO_MMMM_EEEE is the
          default _a_r_g.  The variable _PPPP_WWWW_DDDD is set to the current directory.  The
          shell variable _CCCC_DDDD_PPPP_AAAA_TTTT_HHHH defines the search path for the directory
          containing _a_r_g.  Alternative directory names are separated by a
          colon (_::::).  The default path is _<<<<_nnnn_uuuu_llll_llll_>>>> (specifying the current



                                                                       PPPPaaaaggggeeee 22227777






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          directory).  Note that the current directory is specified by a null
          pathname, which can appear immediately after the equal sign or
          between the colon delimiters anywhere else in the path list.  If _a_r_g
          begins with a _//// the search path is not used.  Otherwise, each
          directory in the path is searched for _a_r_g.

          The second form of _cccc_dddd substitutes the string _n_e_w for the string _o_l_d
          in the current directory name, _PPPP_WWWW_DDDD and tries to change to this new
          directory.

          If you specify _----_LLLL, _ssss_hhhh does not resolve symbolic links.  This is the
          default behavior.

          If you specify _----_PPPP, _ssss_hhhh resolves all symbolic links.

          If you specify both _----_LLLL and _----_PPPP, the last option specifies the
          behavior.

          The _cccc_dddd command may not be executed by restricted _ssss_hhhh.

     _eeee_cccc_hhhh_oooo [ _a_r_g ... ]
          See _eeee_cccc_hhhh_oooo(1) for usage and description.

     _eeee_vvvv_aaaa_llll [ _a_r_g ... ]     *
          The arguments are read as input to the shell and the resulting
          command(s) executed.

     _eeee_xxxx_eeee_cccc [ _a_r_g ... ]     *
          If _a_r_g is given, the command specified by the arguments is executed
          in place of this shell without creating a new process.  Input/output
          arguments may appear and affect the current process.  If no
          arguments are given the effect of this command is to modify file
          descriptors as prescribed by the input/output redirection list.  In
          this case, any file descriptor numbers greater than 2 that are
          opened with this mechanism are closed when invoking another program.

     _eeee_xxxx_iiii_tttt [ _n ]     *
          Causes the shell to exit with the exit status specified by _n.  If _n
          is omitted the exit status is that of the last command executed.  An
          end-of-file also causes the shell to exit except for a shell which
          has the _i_g_n_o_r_e_e_o_f option (see _ssss_eeee_tttt below) turned on.

     _eeee_xxxx_pppp_oooo_rrrr_tttt [ _n_a_m_e[_====_v_a_l_u_e ] ] ...     **
          The given _n_a_m_es are marked for automatic export to the _e_n_v_i_r_o_n_m_e_n_t
          of subsequently-executed commands.

     _eeee_xxxx_pppp_oooo_rrrr_tttt _----_pppp     **
          When _----_pppp is specified, _e_x_p_o_r_t writes to the standard the output names
          and values of all exported variables, in the following format:






                                                                       PPPPaaaaggggeeee 22228888






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



               "export %s=%s\n",< _n_a_m_e >, < _v_a_l_u_e >

          The _----_pppp option allows portable access to the values that can be saved
          and later restored using, for instance, a dot script.

          The shell formats the output, including the proper use of quoting,
          so that it is suitable for reinput to the shell as commands that
          achieve the same exporting results.

     _ffff_cccc [ _----_eeee _e_n_a_m_e ] [ _----_nnnn_llll_rrrr ] [ _f_i_r_s_t [ _l_a_s_t ] ]
     _ffff_cccc _----_eeee _---- [ _o_l_d_====_n_e_w ] [ _c_o_m_m_a_n_d ]
     _ffff_cccc _----_ssss [ _o_l_d_====_n_e_w ] [ _f_i_r_s_t ]
          In the first form, a range of commands from _f_i_r_s_t to _l_a_s_t is
          selected from the last _HHHH_IIII_SSSS_TTTT_SSSS_IIII_ZZZZ_EEEE commands that were typed at the
          terminal.  The arguments _f_i_r_s_t and _l_a_s_t may be specified as a
          [+]number or as a string.  A string is used to locate the most
          recent command starting with the given string.  A negative number is
          used as an offset to the current command number.  If the flag _----_llll, is
          selected, the commands are listed on standard output.  Otherwise,
          the editor program _e_n_a_m_e is invoked on a file containing these
          keyboard commands.  If _e_n_a_m_e is not supplied, the value of the
          variable _FFFF_CCCC_EEEE_DDDD_IIII_TTTT (default _////_uuuu_ssss_rrrr_////_bbbb_iiii_nnnn_////_eeee_dddd) is used as the editor.  When
          editing is complete, the edited command(s) is executed.  If _l_a_s_t is
          not specified it is set to _f_i_r_s_t.  If _f_i_r_s_t is not specified the
          default is the previous command for editing and -16 for listing.
          The flag _----_rrrr reverses the order of the commands and the flag _----_nnnn
          suppresses command numbers when listing.  In the second form the
          _c_o_m_m_a_n_d is re-executed after the substitution _o_l_d_====_n_e_w is performed.
          In the third form the _c_o_m_m_a_n_d is re-executed after the substitution
          _o_l_d_====_n_e_w is performed without invoking an editor.

     _ffff_gggg [ _j_o_b... ]
          This command is only on systems that support job control.  Each _j_o_b
          specified is brought to the foreground.  Otherwise, the current job
          is brought into the foreground.  See JJJJoooobbbbssss for a description of the
          format of _j_o_b.

     _gggg_eeee_tttt_oooo_pppp_tttt_ssss _o_p_t_s_t_r_i_n_g _n_a_m_e [ _a_r_g ... ]
          Checks _a_r_g for legal options.  If _a_r_g is omitted, the positional
          parameters are used.  An option argument begins with a _++++ or a _----.  An
          option not beginning with _++++ or _---- or the argument _----_---- ends the
          options.  _o_p_t_s_t_r_i_n_g contains the letters that _gggg_eeee_tttt_oooo_pppp_tttt_ssss recognizes.
          If a letter is followed by a _::::, that option is expected to have an
          argument.  The options can be separated from the argument by blanks.

          _gggg_eeee_tttt_oooo_pppp_tttt_ssss places the next option letter it finds inside variable _n_a_m_e
          each time it is invoked with a _++++ prepended when _a_r_g begins with a _++++.
          The index of the next _a_r_g is stored in _OOOO_PPPP_TTTT_IIII_NNNN_DDDD.  The option argument,
          if any, gets stored in _OOOO_PPPP_TTTT_AAAA_RRRR_GGGG.  Whenever the shell is invoked,
          _OOOO_PPPP_TTTT_IIII_NNNN_DDDD is initialized to 1.





                                                                       PPPPaaaaggggeeee 22229999






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          A leading _:::: in _o_p_t_s_t_r_i_n_g causes _gggg_eeee_tttt_oooo_pppp_tttt_ssss to store the letter of an
          invalid option in _OOOO_PPPP_TTTT_AAAA_RRRR_GGGG, and to set _n_a_m_e to _????  for an unknown
          option and to _:::: when a required option is missing.  Otherwise,
          _gggg_eeee_tttt_oooo_pppp_tttt_ssss prints an error message.  The exit status is nonzero when
          there are no more options.

     _jjjj_oooo_bbbb_ssss [ _----_llll_nnnn_pppp ] [ _j_o_b ... ]
          Lists information about each given job; or all active jobs if _j_o_b is
          omitted.  The _----_llll flag lists process ids in addition to the normal
          information.  The _----_nnnn flag only displays jobs that have stopped or
          exited since last notified.  The _----_pppp flag causes only the process
          group to be listed.  See JJJJoooobbbbssss for a description of the format of
          _j_o_b.

     _kkkk_iiii_llll_llll [ -_s_i_g ] _j_o_b ...
     _kkkk_iiii_llll_llll [ -_s_i_g ] -1
     _kkkk_iiii_llll_llll _----_ssss _s_i_g_n_a_l__n_a_m_e _j_o_b ...
     _kkkk_iiii_llll_llll _----_llll [ _e_x_i_t__s_t_a_t_u_s ]
          Sends either the TERM (terminate) signal or the specified signal to
          the specified jobs or processes.  In the second form, the TERM
          (terminate) or specified signal is sent to all processes owned by
          the user.  Signals are either given by number or by names (as given
          in _////_uuuu_ssss_rrrr_////_iiii_nnnn_cccc_llll_uuuu_dddd_eeee_////_ssss_iiii_gggg_nnnn_aaaa_llll_...._hhhh, stripped of the prefix ``SIG'').  If the
          signal being sent is TERM (terminate) or HUP (hangup), the job or
          process is sent a CONT (continue) signal if it is stopped.  The
          argument _j_o_b can the process id of a process that is not a member of
          one of the active jobs.  See JJJJoooobbbbssss for a description of the format of
          _j_o_b.  In the fourth form, _kkkk_iiii_llll_llll _----_llll, the signal numbers and names are
          listed.  If an _e_x_i_t__s_t_a_t_u_s operand is given and it is the unsigned
          decimal integer value of a signal number, the _s_i_g_n_a_l__n_a_m_e (the
          specification-defined symbolic constant name without the ``SIG''
          prefix) corresponding to that signal is written.

     _llll_eeee_tttt _a_r_g ...
          Each _a_r_g is a separate _a_r_i_t_h_m_e_t_i_c _e_x_p_r_e_s_s_i_o_n to be evaluated.  See
          AAAArrrriiiitttthhhhmmmmeeeettttiiiicccc EEEEvvvvaaaalllluuuuaaaattttiiiioooonnnn above, for a description of arithmetic
          expression evaluation.

          The exit status is 0 if the value of the last expression is nonzero,
          and 1 otherwise.

     _llll_iiii_mmmm_iiii_tttt [ _----_hhhh ] _r_e_s_o_u_r_c_e _m_a_x_i_m_u_m-_u_s_e
          This is the Bourne shell version included for backward
          compatibility.  Limits the consumption by the current process and
          each process it creates to not individually exceed _m_a_x_i_m_u_m-_u_s_e on
          the specified _r_e_s_o_u_r_c_e.  If no _m_a_x_i_m_u_m-_u_s_e is given, then the
          current limit is printed; if no _r_e_s_o_u_r_c_e is given, then all
          limitations are given.  If the ----hhhh flag is given, the hard limits are
          used instead of the current limits.  The hard limits impose a
          ceiling on the values of the current limits.  Only the superuser can
          raise the hard limits, but a user can lower or raise the current
          limits within the legal range.



                                                                       PPPPaaaaggggeeee 33330000






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          Resources controllable currently include _c_p_u_t_i_m_e, the maximum number
          of cpu-seconds to be used by each process, _f_i_l_e_s_i_z_e, the largest
          single file that can be created, _d_a_t_a_s_i_z_e, the maximum growth of the
          data region via _s_b_r_k(2) beyond the end of the program text,
          _s_t_a_c_k_s_i_z_e, the maximum size of the automatically-extended stack
          region, _c_o_r_e_d_u_m_p_s_i_z_e, the size of the largest core dump created,
          _m_e_m_o_r_y_u_s_e, the maximum amount of physical memory a process can have
          allocated to it at a given time, _d_e_s_c_r_i_p_t_o_r_s, the maximum number of
          open files, _v_m_e_m_o_r_y, the maximum total virtual size of the process,
          including text, data, heap, shared memory, mapped files, stack, and
          so on, and _t_h_r_e_a_d_s, the maximum number of _p_t_h_r_e_a_d_s(5) the process
          may create.

          The _m_a_x_i_m_u_m-_u_s_e can be given as a (floating point or integer) number
          followed by a scale factor.  For all limits other than _c_p_u_t_i_m_e,
          _d_e_s_c_r_i_p_t_o_r_s and _t_h_r_e_a_d_s the default scale is kkkk or kkkkiiiilllloooobbbbyyyytttteeeessss (1024
          bytes); a scale factor of mmmm or mmmmeeeeggggaaaabbbbyyyytttteeeessss can also be used.  For
          _c_p_u_t_i_m_e the default scaling is sssseeeeccccoooonnnnddddssss, while mmmm for minutes or hhhh for
          hours, or a time of the form _m_m::::_s_s giving minutes and seconds can be
          used.

          For both _r_e_s_o_u_r_c_e names and scale factors, unambiguous prefixes of
          the names suffice.

     _nnnn_eeee_wwww_gggg_rrrr_pppp [ _----_llll ] [ _a_r_g ]     *
     _nnnn_eeee_wwww_gggg_rrrr_pppp [ _---- ] [ _a_r_g ]     *
          Equivalent to _eeee_xxxx_eeee_cccc _////_uuuu_ssss_rrrr_////_bbbb_iiii_nnnn_////_nnnn_eeee_wwww_gggg_rrrr_pppp _a_r_g.  The _----_llll (ell) or the _----
          option change the environment to what would be expected if the user
          actually logged in again.

     _pppp_rrrr_iiii_nnnn_tttt [ _----_RRRR_nnnn_pppp_rrrr_ssss_uuuu[_n ] ] [ _a_r_g ... ]
          The shell output mechanism.  With no flags or with flag _---- or _----_---- the
          arguments are printed on standard output as described by _eeee_cccc_hhhh_oooo(1).
          In raw mode, _----_RRRR or _----_rrrr, the escape conventions of _eeee_cccc_hhhh_oooo are ignored.
          The _----_RRRR option prints all subsequent arguments and options other than
          _----_nnnn.  The _----_pppp option causes the arguments to be written onto the pipe
          of the process spawned with _||||_&&&& instead of standard output.  The _----_ssss
          option causes the arguments to be written onto the history file
          instead of standard output.  The _----_uuuu flag can be used to specify a
          one digit file descriptor unit number _nnnn on which the output is
          placed.  The default is 1.  If the flag _----_nnnn is used, no newline is
          added to the output.

     _pppp_wwww_dddd _[[[[ _----_LLLL_PPPP _]]]]
          This is equivalent to _pppp_rrrr_iiii_nnnn_tttt _----_rrrr _---- _$$$$_PPPP_WWWW_DDDD if you have not changed _PPPP_WWWW_DDDD.

          If you specify _----_LLLL, _ssss_hhhh does not resolve symbolic links.  This is the
          default behavior.

          If you specify _----_PPPP, _ssss_hhhh resolves all symbolic links.





                                                                       PPPPaaaaggggeeee 33331111






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          If you specify both _----_LLLL and _----_PPPP, the last option specifies the
          behavior.

     _rrrr_eeee_aaaa_dddd [ _----_pppp_rrrr_ssss_uuuu[ _n ] ] [ _n_a_m_e_????_p_r_o_m_p_t ] [ _n_a_m_e ... ]
          The shell input mechanism.  One line is read and is broken up into
          fields using the characters in _IIII_FFFF_SSSS as separators.  In raw mode, _----_rrrr_,,,,
          a _\\\\ at the end of a line does not signify line continuation.  The
          first field is assigned to the first _n_a_m_e, the second field to the
          second _n_a_m_e, and so on, with leftover fields assigned to the last
          _n_a_m_e.  The _----_pppp option causes the input line to be taken from the
          input pipe of a process spawned by the shell using _||||_&&&&.  If the _----_ssss
          flag is present, the input is saved as a command in the history
          file.  The flag _----_uuuu can be used to specify a one digit file
          descriptor unit to read from.  The file descriptor can be opened
          with the _eeee_xxxx_eeee_cccc special command.  The default value of _n is 0.  If
          _n_a_m_e is omitted _RRRR_EEEE_PPPP_LLLL_YYYY is used as the default _n_a_m_e.  The exit status
          is 0 unless an end-of-file is encountered.  An end-of-file with the
          _----_pppp option causes cleanup for this process so that another can be
          spawned.  If the first argument contains a _????, the remainder of this
          word is used as a _p_r_o_m_p_t on standard error when the shell is
          interactive.  The exit status is 0 unless an end-of-file is
          encountered.

     _rrrr_eeee_aaaa_dddd_oooo_nnnn_llll_yyyy [ _n_a_m_e[_====_v_a_l_u_e] ] ...     **
          The given _n_a_m_es are marked readonly and these names cannot be
          changed by subsequent assignment.

     _rrrr_eeee_aaaa_dddd_oooo_nnnn_llll_yyyy _----_pppp     **
          When _----_pppp is specified, _r_e_a_d_o_n_l_y writes to the standard the output
          names and values of all read-only variables, in the following
          format:

               "readonly %s=%s\n",< _n_a_m_e >, < _v_a_l_u_e >

          The _----_pppp option allows portable access to the values that can be saved
          and later restored using, for instance, a dot script.

          The shell formats the output, including the proper use of quoting,
          so that it is suitable for reinput to the shell as commands that
          achieve the same attribute-setting results.

     _rrrr_eeee_tttt_uuuu_rrrr_nnnn [ _n ]     *
          Causes a shell _f_u_n_c_t_i_o_n to return to the invoking script with the
          return status specified by _n.  If _n is omitted the return status is
          that of the last command executed.  If _rrrr_eeee_tttt_uuuu_rrrr_nnnn is invoked while not
          in a _f_u_n_c_t_i_o_n or a _....  script, it is the same as an _eeee_xxxx_iiii_tttt.

     _ssss_eeee_tttt [ _----_aaaa_bbbb_CCCC_eeee_ffff_hhhh_kkkk_mmmm_nnnn_pppp_ssss_tttt_uuuu_vvvv_xxxx ] [ _----_oooo _o_p_t_i_o_n ] [ _----_AAAA _n_a_m_e ] [ _a_r_g ... ]     *
          The flags for this command have meaning as follows:






                                                                       PPPPaaaaggggeeee 33332222






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          _----_AAAA   Array assignment.  Unset the variable _n_a_m_e and assign values
               sequentially from the list _a_r_g.  If _++++_AAAA is used, the variable
               _n_a_m_e is not unset first.

          _----_aaaa   All subsequent variables that are defined are automatically
               exported.

          _----_bbbb   Cause the shell to notify the user asynchronously of background
               job completions.  When the shell notifies the user a job has
               been completed, it may remove the job's process ID from the
               list of those known in the current shell execution environment.
               Asynchronous notification is not enabled by default.

          _----_CCCC   (Upper-case C) Prevent existing files from being overwritten by
               the shell's > redirection operator.  The >| redirection
               operator overrides this _n_o_c_l_o_b_b_e_r option for an individual
               file.

          _----_eeee   If a command has a nonzero exit status, execute the _EEEE_RRRR_RRRR trap,
               if set, and exit.  This mode is disabled while reading
               profiles.

          _----_ffff   Disables filename generation.

          _----_hhhh   Each command becomes a tracked alias when first encountered.

          _----_kkkk   All variable assignment arguments are placed in the environment
               for a command, not just those that precede the command name.

          _----_mmmm   Background jobs run in a separate process group and a line
               prints upon completion.  The exit status of background jobs is
               reported in a completion message.  On systems with job control,
               this flag is turned on automatically for interactive shells.

          _----_nnnn   Read commands and check them for syntax errors, but do not
               execute them.  Ignored for interactive shells.

          _----_oooo   The following argument can be one of the following option
               names:

               _aaaa_llll_llll_eeee_xxxx_pppp_oooo_rrrr_tttt    Same as _----_aaaa.

               _eeee_rrrr_rrrr_eeee_xxxx_iiii_tttt      Same as _----_eeee.

               _bbbb_gggg_nnnn_iiii_cccc_eeee       All background jobs are run at a lower priority.
                            This is the default mode.

               _eeee_mmmm_aaaa_cccc_ssss        Puts you in an _e_m_a_c_s style in-line editor for
                            command entry.






                                                                       PPPPaaaaggggeeee 33333333






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



               _iiii_gggg_nnnn_oooo_rrrr_eeee_eeee_oooo_ffff    The shell does not exit on end-of-file.  The
                            command _eeee_xxxx_iiii_tttt must be used.

               _kkkk_eeee_yyyy_wwww_oooo_rrrr_dddd      Same as _----_kkkk.

               _mmmm_aaaa_rrrr_kkkk_dddd_iiii_rrrr_ssss     All directory names resulting from filename
                            generation have a trailing _//// appended.

               _mmmm_oooo_nnnn_iiii_tttt_oooo_rrrr      Same as _----_mmmm.

               _nnnn_oooo_cccc_llll_oooo_bbbb_bbbb_eeee_rrrr    Same as _----_CCCC.

               _nnnn_oooo_eeee_xxxx_eeee_cccc       Same as _----_nnnn.

               _nnnn_oooo_gggg_llll_oooo_bbbb       Same as _----_ffff.

               _nnnn_oooo_llll_oooo_gggg        Do not save function definitions in history file.

               _nnnn_oooo_tttt_iiii_ffff_yyyy       Same as _----_bbbb.

               _nnnn_oooo_uuuu_nnnn_ssss_eeee_tttt      Same as _----_uuuu.

               _pppp_rrrr_iiii_vvvv_iiii_llll_eeee_gggg_eeee_dddd   Same as _----_pppp.

               _vvvv_eeee_rrrr_bbbb_oooo_ssss_eeee      Same as _----_vvvv.

               _tttt_rrrr_aaaa_cccc_kkkk_aaaa_llll_llll     Same as _----_hhhh.

               _vvvv_iiii           Puts you in insert mode of a _vvvv_iiii style inline
                            editor until you hit escape character _0000_3333_3333.  This
                            puts you in move mode.  A return sends the line.

               _vvvv_iiii_rrrr_aaaa_wwww        Each character is processed as it is typed in _vvvv_iiii
                            mode.

               _xxxx_tttt_rrrr_aaaa_cccc_eeee       Same as _----_xxxx.

               If no option name is supplied the current option settings are
               printed.

          _----_pppp   Disables processing of the _$$$$_HHHH_OOOO_MMMM_EEEE_////_...._pppp_rrrr_oooo_ffff_iiii_llll_eeee file and uses the
               file _////_eeee_tttt_cccc_////_ssss_uuuu_iiii_dddd______pppp_rrrr_oooo_ffff_iiii_llll_eeee instead of the _EEEE_NNNN_VVVV file.  This mode is
               on whenever the effective uid (gid) is not equal to the real
               uid (gid).  Turning this off causes the effective uid and gid
               to be set to the real uid and gid.

          _----_ssss   Sort the positional parameters lexicographically.

          _----_tttt   Exit after reading and executing one command.






                                                                       PPPPaaaaggggeeee 33334444






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          _----_uuuu   Treat unset parameters as an error when substituting.

          _----_vvvv   Print shell input lines as they are read.

          _----_xxxx   Print commands and their arguments as they are executed.

          _----    Turns off _----_xxxx and _----_vvvv flags and stops examining arguments for
               flags.

          _----_----   Do not change any of the flags; useful in setting _$$$$_1111 to a value
               beginning with _----.  If no arguments follow this flag the
               positional parameters are unset.

          Using _++++ rather than _---- causes these flags to be turned off.  These
          flags can also be used upon invocation of the shell.  The current
          set of flags may be found in _$$$$_----.  Unless _----_AAAA is specified, the
          remaining arguments are positional parameters and are assigned, in
          order, to _$$$$_1111 _$$$$_2222 ....  If no arguments are given the names and values
          of all variables are printed on the standard output.

     _ssss_hhhh_iiii_ffff_tttt [ _n ]     *
          The positional parameters from _$$$$_n_++++_1111 ...  are renamed _$$$$_1111 ..., default
          _n is 1.  The parameter _n can be any arithmetic expression that
          evaluates to a non-negative number less than or equal to _$$$$_####.

     _tttt_iiii_mmmm_eeee_ssss     *
          Print the accumulated user and system times for the shell and for
          processes run from the shell.

     _tttt_rrrr_aaaa_pppp [ _a_r_g ] [ _s_i_g ] ...     *
          _a_r_g is a command to be read and executed when the shell receives
          signal(s) _s_i_g.  (Note that _a_r_g is scanned once when the trap is set
          and once when the trap is taken.)  Each _s_i_g can be given as a number
          or as the name of the signal.  Trap commands are executed in order
          of signal number.  Any attempt to set a trap on a signal that was
          ignored on entry to the current shell is ineffective.  If _a_r_g is
          omitted or is _----, all trap(s) _s_i_g are reset to their original values.
          If _a_r_g is the null string this signal is ignored by the shell and by
          the commands it invokes.  If _s_i_g is _EEEE_RRRR_RRRR, _a_r_g is executed whenever a
          command has a nonzero exit status.  _s_i_g is _DDDD_EEEE_BBBB_UUUU_GGGG _a_r_g is executed
          after each command.  If _s_i_g is _0000 or _EEEE_XXXX_IIII_TTTT and the _tttt_rrrr_aaaa_pppp statement is
          executed inside the body of a function, the command _a_r_g is executed
          after the function completes.  If _s_i_g is _0000 or _EEEE_XXXX_IIII_TTTT for a _tttt_rrrr_aaaa_pppp set
          outside any function the command _a_r_g is executed on exit from the
          shell.  The _tttt_rrrr_aaaa_pppp command with no arguments prints a list of commands
          associated with each signal number.

     _tttt_yyyy_pppp_eeee_ssss_eeee_tttt [ _++++_____HHHH_LLLL_RRRR_ZZZZ_ffff_iiii_llll_rrrr_tttt_uuuu_xxxx[_n] ] [ _n_a_m_e[_====_v_a_l_u_e ] ] ...     **
          Sets attributes and values for shell variables.  When invoked inside
          a function, a new instance of the variable _n_a_m_e is created.  The
          parameter value and type are restored when the function completes.
          The following list of attributes may be specified:



                                                                       PPPPaaaaggggeeee 33335555






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          _----_HHHH   This flag provides UNIX to host-name file mapping on non-UNIX
               machines.

          _----_LLLL   Left justify and remove leading blanks from _v_a_l_u_e.  If _n is
               nonzero it defines the width of the field, otherwise it is
               determined by the width of the value of first assignment.  When
               the variable is assigned to, it is filled on the right with
               blanks or truncated, if necessary, to fit into the field.
               Leading zeros are removed if the _----_ZZZZ flag is also set.  The _----_RRRR
               flag is turned off.

          _----_RRRR   Right justify and fill with leading blanks.  If _n is nonzero it
               defines the width of the field, otherwise it is determined by
               the width of the value of first assignment.  The field is left
               filled with blanks or truncated from the end if the variable is
               reassigned.  The _LLLL flag is turned off.

          _----_ZZZZ   Right justify and fill with leading zeros if the first non-
               blank character is a digit and the _----_LLLL flag has not been set.
               If _n is nonzero it defines the width of the field, otherwise it
               is determined by the width of the value of first assignment.

          _----_ffff   The names refer to function names rather than variable names.
               No assignments can be made and the only other valid flags are
               _----_tttt, _----_uuuu and _----_xxxx.  The flag _----_tttt turns on execution tracing for this
               function.  The flag _----_uuuu causes this function to be marked
               undefined.  The _FFFF_PPPP_AAAA_TTTT_HHHH variable is searched to find the function
               definition when the function is referenced.  The flag _----_xxxx allows
               the function definition to remain in effect across shell
               procedures invoked by name.

          _----_iiii   Variable is an integer.  This makes arithmetic faster.  If _n is
               nonzero it defines the output arithmetic base, otherwise the
               first assignment determines the output base.

          _----_llll   All upper-case characters converted to lower-case.  The upper-
               case flag, _----_uuuu is turned off.

          _----_rrrr   The given _n_a_m_es are marked readonly and these names cannot be
               changed by subsequent assignment.

          _----_tttt   Tags the variables.  Tags are user definable and have no
               special meaning to the shell.

          _----_uuuu   All lower-case characters are converted to upper-case
               characters.  The lower-case flag, _----_llll is turned off.

          _----_xxxx   The given _n_a_m_es are marked for automatic export to the
               _e_n_v_i_r_o_n_m_e_n_t of subsequently-executed commands.






                                                                       PPPPaaaaggggeeee 33336666






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          Using _++++ rather than _---- causes these flags to be turned off.  If no
          _n_a_m_e arguments are given but flags are specified, a list of _n_a_m_e_s
          (and optionally the _vvvv_aaaa_llll_uuuu_eeee_ssss) of the _v_a_r_i_a_b_l_e_s which have these flags
          set is printed.  (Using _++++ rather than _---- keeps the values from being
          printed.)  If no _n_a_m_es and flags are given, the _n_a_m_e_s and _a_t_t_r_i_b_u_t_e_s
          of all _v_a_r_i_a_b_l_e_s are printed.

     _uuuu_llll_iiii_mmmm_iiii_tttt [ _----_[[[[_HHHH_SSSS_]]]]_[[[[_aaaa _|||| _cccc_dddd_ffff_nnnn_ssss_tttt_vvvv_mmmm_pppp_]]]] ]
     _uuuu_llll_iiii_mmmm_iiii_tttt [ _----_[[[[_HHHH_SSSS_]]]]_[[[[_cccc _|||| _dddd _|||| _ffff _|||| _nnnn _|||| _ssss _|||| _tttt _|||| _vvvv _|||| _mmmm _|||| _pppp_]]]] _]]]] _l_i_m_i_t
          _uuuu_llll_iiii_mmmm_iiii_tttt prints or sets hard or soft resource limits.  These limits
          are described in _gggg_eeee_tttt_rrrr_llll_iiii_mmmm_iiii_tttt(2).

          If _l_i_m_i_t is not present, _uuuu_llll_iiii_mmmm_iiii_tttt prints the specified limits.  Any
          number of limits may be printed at one time.  The _----_aaaa option prints
          all limits.

          If _l_i_m_i_t is present, _uuuu_llll_iiii_mmmm_iiii_tttt sets the specified limit to _l_i_m_i_t.  The
          string _uuuu_nnnn_llll_iiii_mmmm_iiii_tttt_eeee_dddd requests the largest valid limit.  Limits may be
          set for only one resource at a time.  Any user may set a soft limit
          to any value below the hard limit.  Any user may lower a hard limit.
          Only a privileged user may raise a hard limit; see _ssss_uuuu(1M).

          The _----_HHHH option specifies a hard limit.  The _----_SSSS option specifies a
          soft limit.  If neither option is specified, _uuuu_llll_iiii_mmmm_iiii_tttt sets both limits
          and prints the soft limit.

          The following options specify the resource whose limits are to be
          printed or set.  If no option is specified, the file size limit is
          printed or set.

          _----_cccc   maximum core file size (in 512-byte blocks)

          _----_dddd   maximum size of data segment or heap (in kbytes)

          _----_ffff   maximum file size (in 512-byte blocks)

          _----_nnnn   maximum file descriptor plus 1

          _----_ssss   maximum size of stack segment (in kbytes).  Note that if this
               is set too high, _ssss_pppp_rrrr_oooo_cccc(2) may fail.

          _----_tttt   maximum CPU time (in seconds)

          _----_vvvv   maximum size of virtual memory (in kbytes)

          _----_mmmm   maximum size of resident memory (in kbytes)

          _----_pppp   maximum number of _p_t_h_r_e_a_d_s(5) that process may create.

          If no option is given, _----_ffff is assumed.





                                                                       PPPPaaaaggggeeee 33337777






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     _uuuu_mmmm_aaaa_ssss_kkkk [ _----_SSSS ][ _m_a_s_k ]
          The user file-creation mask is set to _m_a_s_k [see _uuuu_mmmm_aaaa_ssss_kkkk(2)].  _m_a_s_k can
          either be an octal number or a symbolic value as described in
          _cccc_hhhh_mmmm_oooo_dddd(1).  If a symbolic value is given, the new umask value is the
          complement of the result of applying _m_a_s_k to the complement of the
          previous umask value.  If _m_a_s_k is omitted, the current value of the
          mask is printed.  If _----_SSSS is specified, the symbolic output is in the
          following format:

               "u=%s,g=%s,o=%s\n", _o_w_n_e_r, _g_r_o_u_p, _o_t_h_e_r

          where the three values are permissions combinations of the letters
          from the set {r,w,x}.

     _uuuu_nnnn_aaaa_llll_iiii_aaaa_ssss _n_a_m_e ...
     _uuuu_nnnn_aaaa_llll_iiii_aaaa_ssss _----_aaaa
          The variables given by the list of _n_a_m_es are removed from the _a_l_i_a_s
          list.  In the second form, all alias definitions are removed from
          the current shell execution environment.

     _uuuu_nnnn_llll_iiii_mmmm_iiii_tttt [ _----_hhhh ] _r_e_s_o_u_r_c_e
          This is the Bourne shell version included for backward
          compatibility.  Removes the limitation on _r_e_s_o_u_r_c_e.  If no _r_e_s_o_u_r_c_e
          is specified, then all _r_e_s_o_u_r_c_e limitations are removed.  If ----hhhh is
          given, the corresponding hard limits are removed.  Only the
          superuser can do this. (See lllliiiimmmmiiiitttt above)

     _uuuu_nnnn_ssss_eeee_tttt [ _----_ffff_vvvv ] _n_a_m_e ...     *
          The variables given by the list of _n_a_m_es are unassigned, i.  e.,
          their values and attributes are erased.  Read-only variables cannot
          be unset.  If the flag, _----_vvvv, is set, the names refer to _v_a_r_i_a_b_l_e
          names.  This is the default when no options are specified.  If the
          flag, _----_ffff, is set, the names refer to _f_u_n_c_t_i_o_n names.  Unsetting
          _EEEE_RRRR_RRRR_NNNN_OOOO, _LLLL_IIII_NNNN_EEEE_NNNN_OOOO, _MMMM_AAAA_IIII_LLLL_CCCC_HHHH_EEEE_CCCC_KKKK, _OOOO_PPPP_TTTT_AAAA_RRRR_GGGG, _OOOO_PPPP_TTTT_IIII_NNNN_DDDD, _RRRR_AAAA_NNNN_DDDD_OOOO_MMMM, _SSSS_EEEE_CCCC_OOOO_NNNN_DDDD_SSSS, _TTTT_MMMM_OOOO_UUUU_TTTT,
          and _____ causes removes their special meaning even if they are
          subsequently assigned to.  In some shell invocations, unsetting
          variables not previously set or null returns a value of 0.  (See the
          _CCCC_OOOO_MMMM_PPPP_AAAA_TTTT_IIII_BBBB_IIII_LLLL_IIII_TTTT_YYYY _IIII_SSSS_SSSS_UUUU_EEEE_SSSS section at the end of this document.)

     _wwww_aaaa_iiii_tttt [ _j_o_b ]     *
          Wait for the specified _j_o_b and report its termination status.  If
          _j_o_b is not given all currently active child processes are waited
          for.  The exit status from this command is that of the process
          waited for.  See JJJJoooobbbbssss for a description of the format of _j_o_b.

     _wwww_hhhh_eeee_nnnn_cccc_eeee [ _----_pppp_vvvv ] _n_a_m_e ...
          For each _n_a_m_e, indicate how it is interpreted if used as a command
          name.

          _----_vvvv   produces a more verbose report.





                                                                       PPPPaaaaggggeeee 33338888






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          _----_pppp   does a path search for _n_a_m_e even if name is an alias, a
               function, or a reserved word.

   IIIInnnnvvvvooooccccaaaattttiiiioooonnnn
     If the shell is invoked by _eeee_xxxx_eeee_cccc(2), and the first character of argument
     zero (_$$$$_0000) is _----, the shell is assumed to be a _llll_oooo_gggg_iiii_nnnn shell and commands are
     read from _////_eeee_tttt_cccc_////_pppp_rrrr_oooo_ffff_iiii_llll_eeee and then from either _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee in the current
     directory or _$$$$_HHHH_OOOO_MMMM_EEEE_////_...._pppp_rrrr_oooo_ffff_iiii_llll_eeee, if either file exists.  Next, commands are
     read from the filenamed by performing parameter substitution on the value
     of the environment variable _EEEE_NNNN_VVVV if the file exists.  If the _----_ssss flag is
     not present and _a_r_g is, a path search is performed on the first _a_r_g to
     determine the name of the script to execute.  The script _a_r_g must have
     read permission and any _ssss_eeee_tttt_uuuu_iiii_dddd and _ssss_eeee_tttt_gggg_iiii_dddd settings are ignored.  Commands
     are read as described below; the following flags are interpreted by the
     shell when it is invoked:

     _----_cccc _s_t_r_i_n_g   If the _----_cccc flag is present commands are read from _s_t_r_i_n_g.

     _----_ssss          If the _----_ssss flag is present or if no arguments remain, commands
                 are read from the standard input.  Shell output, except for
                 the output of the Special commands listed above, is written
                 to file descriptor 2.

     _----_iiii          If the _----_iiii flag is present or if the shell input and output
                 are attached to a terminal (as told by _iiii_oooo_cccc_tttt_llll(2)) this shell
                 is _i_n_t_e_r_a_c_t_i_v_e.  In this case TERM is ignored (so that _kkkk_iiii_llll_llll _0000
                 does not kill an interactive shell) and INTR is caught and
                 ignored (so that _wwww_aaaa_iiii_tttt is interruptible).  In all cases, QUIT
                 is ignored by the shell.

     _----_rrrr          If the _----_rrrr flag is present the shell is a restricted shell.

     The remaining flags and arguments are described under the _ssss_eeee_tttt command
     above.

   RRRReeeessssttttrrrriiiicccctttteeeedddd sssshhhh OOOOnnnnllllyyyy
     The restricted _ssss_hhhh is used to set up login names and execution
     environments whose capabilities are more controlled than those of the
     standard shell.  The actions of the restricted _ssss_hhhh are identical to those
     of _ssss_hhhh, except that the following are disallowed:

          Changing directory [see _cccc_dddd(1)]
          Setting the value of _SSSS_HHHH_EEEE_LLLL_LLLL, _EEEE_NNNN_VVVV, or _PPPP_AAAA_TTTT_HHHH
          Specifying path or command names containing _////
          Redirecting output (_>>>>, _>>>>_||||_,,,, _<<<<_>>>>_,,,, and _>>>>_>>>>)

     The restrictions above are enforced after _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee and the _EEEE_NNNN_VVVV files are
     interpreted.

     When a command to be executed is found to be a shell procedure, the
     restricted _ssss_hhhh invokes _ssss_hhhh to execute it.  Thus, it is possible to provide
     to the end-user shell procedures that have access to the full power of



                                                                       PPPPaaaaggggeeee 33339999






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



     the standard shell, while imposing a limited menu of commands; this
     scheme assumes that the end-user does not have write and execute
     permissions in the same directory.

     The net effect of these rules is that the writer of the _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee has
     complete control over user actions, by performing guaranteed setup
     actions and leaving the user in an appropriate directory (probably not
     the login directory).

     The system administrator often sets up a directory of commands (that is,
     _////_uuuu_ssss_rrrr_////_rrrr_bbbb_iiii_nnnn) that can be safely invoked by the restricted _ssss_hhhh.

     WARNING: Since the restricted _ssss_hhhh depends on _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee to set up
     restrictions, and _...._pppp_rrrr_oooo_ffff_iiii_llll_eeee is only interpreted by login shells, allowing
     a restricted _ssss_hhhh user to access the system in a manor that does not invoke
     a login shell will allow the user to bypass these restrictions.  An
     example of this type of access is remote shell (See _rrrr_ssss_hhhh______bbbb_ssss_dddd(1C)).

EEEEXXXXIIIITTTT SSSSTTTTAAAATTTTUUUUSSSS
     Errors detected by the shell, such as syntax errors, cause the shell to
     return a nonzero exit status.  Otherwise, the shell returns the exit
     status of the last command executed (see also the _eeee_xxxx_iiii_tttt command above).
     If the shell is being used non-interactively, execution of the shell file
     is abandoned.  Run time errors detected by the shell are reported by
     printing the command or function name and the error condition.  If the
     line number that the error occurred on is greater than one, the line
     number is also printed in square brackets (_[[[[_]]]]) after the command or
     function name.

     If a command is not found, the exit status is _1111_2222_7777.  If the command name
     is found, but it is not an executable utility, the exit status is _1111_2222_6666.
     Applications that invoke utilities without using the shell should use
     these exit status values to report similar errors.

     If a command fails during word expansion or redirection, its exit status
     is greater than zero.

     Internally, for purposes of deciding if a command exits with a nonzero
     exit status, the shell recognizes the entire status value retrieved for
     the command by the equivalent of the _w_a_i_t() function WEXITSTATUS macro.
     When reporting the exit status with the special parameter ?, the shell
     reports the full eight bits of exit status available.  The exit status of
     a command that terminated because it received a signal is reported as
     greater than _1111_2222_8888_....

FFFFIIIILLLLEEEESSSS
     /etc/passwd
     /etc/profile
     /etc/suid_profile
     $HOME/_....profile
     /tmp/sh*
     /dev/null



                                                                       PPPPaaaaggggeeee 44440000






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



SSSSEEEEEEEE AAAALLLLSSSSOOOO
     emacs(1), cat(1), cd(1), chmod(1), cut(1), echo(1), env(1), newgrp(1M),
     paste(1), stty(1), test(1), umask(1), vi(1), dup(2), exec(2), fork(2),
     ioctl(2), lseek(2), pipe(2), signal(2), ulimit(2), umask(2), wait(2),
     rand(3C), a.out(4), profile(4), environ(5).

     Morris I. Bolsky and David G. Korn, _T_h_e _K_o_r_n_S_h_e_l_l _C_o_m_m_a_n_d _a_n_d _P_r_o_g_r_a_m_m_i_n_g
     _L_a_n_g_u_a_g_e, Prentice Hall, 1989

NNNNOOOOTTTTEEEESSSS
     If a command that is a _t_r_a_c_k_e_d _a_l_i_a_s is executed and then a command with
     the same name is installed in a directory in the search path before the
     directory where the original command was found, the shell continues to
     _eeee_xxxx_eeee_cccc the original command.  Use the _----_tttt option of the _aaaa_llll_iiii_aaaa_ssss command to
     correct this situation.

     Some very old shell scripts contain a _^^^^ as a synonym for the pipe
     character _||||.

     Using the _ffff_cccc builtin command within a compound command causes the whole
     command to disappear from the history file.

     The builtin command _.... _f_i_l_e reads the whole file before any commands are
     executed.  Therefore, _aaaa_llll_iiii_aaaa_ssss and _uuuu_nnnn_aaaa_llll_iiii_aaaa_ssss commands in the file do not apply
     to any functions defined in the file.

     Traps are not processed while a job is waiting for a foreground process.
     Thus, a trap on _CCCC_HHHH_LLLL_DDDD won't be executed until the foreground job
     terminates.

     Prior to IRIX Release 5.0, the _rrrr_ssss_hhhh command invoked the restricted shell.
     This restricted shell command is _////_uuuu_ssss_rrrr_////_llll_iiii_bbbb_////_rrrr_ssss_hhhh and it can be executed by
     using the full pathname.  Beginning with IRIX Release 5.0, the _rrrr_ssss_hhhh
     command is the remote shell.  See _rrrr_ssss_hhhh______bbbb_ssss_dddd(1C).

     Sometimes, particularly when using wildcards, the shell will fail to
     execute a command, and complain with the message
        aaaarrrrgggg lllliiiisssstttt ttttoooooooo lllloooonnnngggg
     This can often be avoided by using multiple commands, the _x_a_r_g_s(1)
     command, or by increasing the nnnnccccaaaarrrrggggssss kernel parameter with the
     _s_y_s_t_u_n_e(1m) command.

CCCCOOOOMMMMPPPPAAAATTTTIIIIBBBBIIIILLLLIIIITTTTYYYY IIIISSSSSSSSUUUUEEEESSSS
     To retain some backward compatibility to the Bourne shell, certain Korn
     shell features are controlled by how the shell is invoked and/or the
     current value of the environment variable ______XXXX_PPPP_GGGG.

     When the shell is invoked as _""""_ssss_hhhh_"""", the following features are performed
     only when the current value of the ______XXXX_PPPP_GGGG variable is equal to 1 (one):

          - command substitution of the form "$( command )"
          - arithmetic expression of the form "$(( expression ))"



                                                                       PPPPaaaaggggeeee 44441111






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



          - tilde expansion of pathnames
          - unsetting variables, not previously set or null, returns 0


     When the shell is invoked as _""""_ssss_hhhh_"""" and the current value of the ______XXXX_PPPP_GGGG
     environment variable is not equal to 1 (one), the special positional
     parameter $0, within a function call, is the name of the function.
     Otherwise, it is the name of the invoking shell script.

     When the shell is not invoked as _""""_ssss_hhhh_"""" and the real and effective uid and
     gid differ, the effective uid and gid are set to the real uid and gid.

     With all invocations of the shell, when the current value of the ______XXXX_PPPP_GGGG
     environment variable is equal to 1 (one), the _----_nnnn option of the builtin
     _eeee_cccc_hhhh_oooo command does not suppress the terminating newline and is treated as
     part of the output string.

     Additional incompatibilities are listed below and can be found in the
     Appendix of the _""""_TTTT_hhhh_eeee _KKKK_oooo_rrrr_nnnn_ssss_hhhh_eeee_llll_llll _CCCC_oooo_mmmm_mmmm_aaaa_nnnn_dddd _aaaa_nnnn_dddd _PPPP_rrrr_oooo_gggg_rrrr_aaaa_mmmm_mmmm_iiii_nnnn_gggg _LLLL_aaaa_nnnn_gggg_uuuu_aaaa_gggg_eeee_"""" _((((_BBBB_oooo_llll_ssss_kkkk_yyyy
     _&&&& _KKKK_oooo_rrrr_nnnn_;;;; _PPPP_rrrr_eeee_nnnn_tttt_iiii_cccc_eeee _HHHH_aaaa_llll_llll_))))

     The Korn shell is more restrictive with field comparisons in the builtin
     _tttt_eeee_ssss_tttt command:

          _[[[[ _""""_1111_0000_2222_4444_0000 _ffff_iiii_llll_eeee_nnnn_aaaa_mmmm_eeee_"""" _----_gggg_eeee _1111_0000_2222_4444_0000 _]]]]

     is accepted by the Bourne shell whereas the Korn shell gives a syntax
     error.

     The Korn shell _kkkk_iiii_llll_llll builtin command now handles the special process
     number (-1) for all process owned by the user.  (See the SSSSppppeeeecccciiiiaaaallll CCCCoooommmmmmmmaaaannnnddddssss
     section.)

     The _ffff_aaaa_llll_ssss_eeee command is a builtin for the Korn shell and cannot be defined
     as a function.

     The _cccc_hhhh_dddd_iiii_rrrr is a builtin alias to the _cccc_dddd command. When shell is invoked as
     "ksh", this alias is removed allowing _cccc_hhhh_dddd_iiii_rrrr to be defined as a function.
     When shell is invoked as "sh", this can also be accomplished by
     unaliasing _cccc_hhhh_dddd_iiii_rrrr and then defining it as a function.

     Some Korn shell internal variables are typeset as integers and setting
     them to non-numeric values will cause "bad number" error messages. They
     include _EEEE_RRRR_RRRR_NNNN_OOOO_,,,, _LLLL_IIII_NNNN_EEEE_NNNN_OOOO_,,,, _MMMM_AAAA_IIII_LLLL_CCCC_HHHH_EEEE_CCCC_KKKK_,,,, _OOOO_PPPP_TTTT_IIII_NNNN_DDDD_,,,, _PPPP_PPPP_IIII_DDDD_,,,, _RRRR_AAAA_NNNN_DDDD_OOOO_MMMM_,,,, _SSSS_EEEE_CCCC_OOOO_NNNN_DDDD_SSSS _aaaa_nnnn_dddd
     _TTTT_MMMM_OOOO_UUUU_TTTT_....

     The Korn shell evaluates variable assignment lists before I/O redirection
     unlike the Bourne shell in which order does not matter.

     The Bourne shell (bsh) has been modified to allow fullpath calls of
     Bourne shell builtins using the builtin name POSIX links to
     /sbin/builtin_exec.



                                                                       PPPPaaaaggggeeee 44442222






sssshhhh((((1111))))                                                                    sssshhhh((((1111))))



IIIINNNNTTTTEEEERRRRNNNNAAAATTTTIIIIOOOONNNNAAAALLLLIIIIZZZZAAAATTTTIIIIOOOONNNN
     The shell accepts multibyte input for command line args, file names,
     environment variable names and values, variable arrays, function names,
     history files and shell scripts. Multibyte sequences accepted for the
     _iiii_ssss_pppp_hhhh_oooo_nnnn_oooo_gggg_rrrr_aaaa_mmmm_((((_)))) and _iiii_ssss_iiii_dddd_eeee_oooo_gggg_rrrr_aaaa_mmmm_((((_)))) subroutines are also allowed.

     _NNNN_oooo_tttt_eeee_:::: The _eeee_mmmm_aaaa_cccc_ssss line editing feature is currently supported only with the
     default _CCCC/_PPPP_OOOO_SSSS_IIII_XXXX locale.

     _NNNN_oooo_tttt_eeee_:::: Changing the _LLLL_AAAA_NNNN_GGGG value during a shell session can produce
     undefined results when accessing e.g. variables created under a different
     locale.











































                                                                       PPPPaaaaggggeeee 44443333