Skunkware 5/Skunkware 5.iso/man/cat.1/expect.1

Text File | 1995-07-25 | 141KB | 2,575 lines

     EEEEXXXXPPPPEEEECCCCTTTT((((1111))))       UUUUNNNNIIIIXXXX SSSSyyyysssstttteeeemmmm VVVV ((((22229999 DDDDeeeecccceeeemmmmbbbbeeeerrrr 1111999999994444))))        EEEEXXXXPPPPEEEECCCCTTTT((((1111))))



     NNNNAAAAMMMMEEEE
          Expect - programmed dialogue with interactive programs,
          Version 5

     SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
          eeeexxxxppppeeeecccctttt [ ----ddddDDDDiiiinnnnNNNN ] [ ----cccc _c_m_d_s ] [ ----ffffbbbb ] _c_m_d_f_i_l_e ] [ _a_r_g_s ]

     IIIINNNNTTTTRRRROOOODDDDUUUUCCCCTTTTIIIIOOOONNNN
          EEEExxxxppppeeeecccctttt is a program that "talks" to other interactive
          programs according to a script.  Following the script,
          EEEExxxxppppeeeecccctttt knows what can be expected from a program and what
          the correct response should be.  An interpreted language
          provides branching and high-level control structures to
          direct the dialogue.  In addition, the user can take control
          and interact directly when desired, afterward returning
          control to the script.

          EEEExxxxppppeeeeccccttttkkkk is a mixture of EEEExxxxppppeeeecccctttt and TTTTkkkk.  It behaves just like
          EEEExxxxppppeeeecccctttt and TTTTkkkk's wwwwiiiisssshhhh.  EEEExxxxppppeeeecccctttt can also be used directly in C
          or C++ (that is, without Tcl).  See libexpect(3).

          The name "Expect" comes from the idea of _s_e_n_d/_e_x_p_e_c_t
          sequences popularized by uucp, kermit and other modem
          control programs.  However unlike uucp, EEEExxxxppppeeeecccctttt is
          generalized so that it can be run as a user-level command
          with any program and task in mind.  EEEExxxxppppeeeecccctttt can actually talk
          to several programs at the same time.

          For example, here are some things EEEExxxxppppeeeecccctttt can do:

               o+   Cause your computer to dial you back, so that you
                   can login without paying for the call.

               o+   Start a game (e.g., rogue) and if the optimal
                   configuration doesn't appear, restart it (again and
                   again) until it does, then hand over control to
                   you.

               o+   Run fsck, and in response to its questions, answer
                   "yes", "no" or give control back to you, based on
                   predetermined criteria.

               o+   Connect to another network or BBS (e.g., MCI Mail,
                   CompuServe) and automatically retrieve your mail so
                   that it appears as if it was originally sent to
                   your local system.

               o+   Carry environment variables, current directory, or
                   any kind of information across rlogin, telnet, tip,
                   su, chgrp, etc.

          There are a variety of reasons why the shell cannot perform



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          these tasks.  (Try, you'll see.) All are possible with
          EEEExxxxppppeeeecccctttt.

          In general, EEEExxxxppppeeeecccctttt is useful for running any program which
          requires interaction between the program and the user.  All
          that is necessary is that the interaction can be
          characterized programmatically.  EEEExxxxppppeeeecccctttt can also give the
          user back control (without halting the program being
          controlled) if desired.  Similarly, the user can return
          control to the script at any time.


     UUUUSSSSAAAAGGGGEEEE
          EEEExxxxppppeeeecccctttt reads _c_m_d_f_i_l_e for a list of commands to execute.
          EEEExxxxppppeeeecccctttt may also be invoked implicitly on systems which
          support the #! notation by marking the script executable,
          and making the first line in your script:

               #!/usr/local/bin/expect -f

          Of course, the path must accurately describe where EEEExxxxppppeeeecccctttt
          lives.  /usr/local/bin is just an example.

          The ----cccc flag prefaces a command to be executed before any in
          the script.  The command should be quoted to prevent being
          broken up by the shell.  This option may be used multiple
          times.  Multiple commands may be executed with a single ----cccc
          by separating them with semicolons.  Commands are executed
          in the order they appear. (When using Expectk, this option
          is specified as ----ccccoooommmmmmmmaaaannnndddd.)

          The ----dddd flag enables some diagnostic output, which primarily
          reports internal activity of commands such as eeeexxxxppppeeeecccctttt and
          iiiinnnntttteeeerrrraaaacccctttt.  This flag has the same effect as "exp_internal 1"
          at the beginning of an Expect script, plus the version of
          EEEExxxxppppeeeecccctttt is printed.  (The ssssttttrrrraaaacccceeee command is useful for
          tracing statements, and the ttttrrrraaaacccceeee command is useful for
          tracing variable assignments.) (When using Expectk, this
          option is specified as ----ddddiiiiaaaagggg.)

          The ----DDDD flag enables an interactive debugger.  An integer
          value should follow.  The debugger will take control before
          the next Tcl procedure if the value is non-zero or if a ^C
          is pressed (or a breakpoint is hit, or other appropriate
          debugger command appears in the script).  See the README
          file or SEE ALSO (below) for more information on the
          debugger.  (When using Expectk, this option is specified as
          ----DDDDeeeebbbbuuuugggg.)

          The ----ffff flag prefaces a file from which to read commands
          from.  The flag itself is optional as it is only useful when
          using the #! notation (see above), so that other arguments



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          may be supplied on the command line.  (When using Expectk,
          this option is specified as ----ffffiiiilllleeee.)

          By default, the command file is read into memory and
          executed in its entirety.  It is occasionally desirable to
          read files one line at a time.  For example, stdin is read
          this way.  In order to force arbitrary files to be handled
          this way, use the ----bbbb flag.  (When using Expectk, this option
          is specified as ----bbbbuuuuffffffffeeeerrrr.)

          If the string "-" is supplied as a filename, standard input
          is read instead.  (Use "./-" to read from a file actually
          named "-".)

          The ----iiii flag causes EEEExxxxppppeeeecccctttt to interactively prompt for
          commands instead of reading them from a file.  Prompting is
          terminated via the eeeexxxxiiiitttt command or upon EOF.  See
          iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr (below) for more information.  ----iiii is assumed if
          neither a command file nor ----cccc is used.  (When using Expectk,
          this option is specified as ----iiiinnnntttteeeerrrraaaaccccttttiiiivvvveeee.)


          -------- may be used to delimit the end of the options.  This is
          useful if you want to pass an option-like argument to your
          script without it being interpreted by EEEExxxxppppeeeecccctttt.  This can
          usefully be placed in the #! line to prevent any flag-like
          interpretation by Expect.  For example, the following will
          leave the original arguments (including the script name) in
          the variable _a_r_g_v.

               #!/usr/local/bin/expect --

          Note that the usual getopt(3) and execve(2) conventions must
          be observed when adding arguments to the #! line.

          The file $exp_library/expect.rc is sourced automatically if
          present, unless the ----NNNN flag is used. (When using Expectk,
          this option is specified as ----NNNNOOOORRRRCCCC.) Immediately after this,
          the file ~/.expect.rc is sourced automatically, unless the
          ----nnnn flag is used.  If the environment variable DOTDIR is
          defined, it is treated as a directory and .expect.rc is read
          from there.  (When using Expectk, this option is specified
          as ----nnnnoooorrrrcccc.) This sourcing occurs only after executing any ----cccc
          flags.

          Optional _a_r_g_s are constructed into a list and stored in the
          variable named _a_r_g_v.  _a_r_g_c is initialized to the length of
          argv.

          _a_r_g_v_0 is defined to be the name of the script (or binary if
          no script is used).  For example, the following prints out
          the name of the script and the first three arguments:



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               send_user "$argv0 [lrange $argv 0 2]\n"


     CCCCOOOOMMMMMMMMAAAANNNNDDDDSSSS
          EEEExxxxppppeeeecccctttt uses _T_c_l (Tool Command Language).  Tcl provides
          control flow (e.g., if, for, break), expression evaluation
          and several other features such as recursion, procedure
          definition, etc.  Commands used here but not defined (e.g.,
          sssseeeetttt, iiiiffff, eeeexxxxeeeecccc) are Tcl commands (see tcl(3)).  EEEExxxxppppeeeecccctttt
          supports additional commands, described below.  Unless
          otherwise specified, commands return the empty string.

          Commands are listed alphabetically so that they can be
          quickly located.  However, new users may find it easier to
          start by reading the descriptions of ssssppppaaaawwwwnnnn, sssseeeennnndddd, eeeexxxxppppeeeecccctttt,
          and iiiinnnntttteeeerrrraaaacccctttt, in that order.

          Note that the best introduction to the language (both Expect
          and Tcl) is provided in the book "Exploring Expect" (see SEE
          ALSO below).  Examples are included in this man page but
          they are very limited since this man page is meant primarily
          as reference material.

          Note that in the text of this man page, "Expect" with an
          uppercase "E" refers to the EEEExxxxppppeeeecccctttt program while "expect"
          with a lower-case "e" refers to the eeeexxxxppppeeeecccctttt command within
          the EEEExxxxppppeeeecccctttt program.)

          cccclllloooosssseeee [-_s_l_a_v_e] [-_o_n_e_x_e_c _0|_1] [-_i _s_p_a_w_n__i_d]
                    closes the connection to the current process.
                    Most interactive programs will detect EOF on their
                    stdin and exit; thus cccclllloooosssseeee usually suffices to
                    kill the process as well.  The ----iiii flag declares
                    the process to close corresponding to the named
                    spawn_id.

                    Both eeeexxxxppppeeeecccctttt and iiiinnnntttteeeerrrraaaacccctttt will detect when the
                    current process exits and implicitly do a cccclllloooosssseeee.
                    But if you kill the process by, say, "exec kill
                    $pid", you will need to explicitly call cccclllloooosssseeee.

                    The ----oooonnnneeeexxxxeeeecccc flag determines whether the spawn id
                    will be closed in any new spawned processes or if
                    the process is overlayed.  To leave a spawn id
                    open, use the value 0.  A non-zero integer value
                    will force the spawn closed (the default) in any
                    new processes.

                    The ----ssssllllaaaavvvveeee flag closes the slave associated with
                    the spawn id.  (See "spawn -pty".) When the
                    connection is closed, the slave is automatically
                    closed as well if still open.



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                    No matter whether the connection is closed
                    implicitly or explicitly, you should call wwwwaaaaiiiitttt to
                    clear up the corresponding kernel process slot.
                    cccclllloooosssseeee does not call wwwwaaaaiiiitttt since there is no
                    guarantee that closing a process connection will
                    cause it to exit.  See wwwwaaaaiiiitttt below for more info.

          ddddeeeebbbbuuuugggg [[-_n_o_w] _0|_1]
                    controls a Tcl debugger allowing you to step
                    through statements, set breakpoints, etc.

                    With no arguments, a 1 is returned if the debugger
                    is not running, otherwise a 0 is returned.

                    With a 1 argument, the debugger is started.  With
                    a 0 argument, the debugger is stopped.  If a 1
                    argument is preceded by the ----nnnnoooowwww flag, the
                    debugger is started immediately (i.e., in the
                    middle of the ddddeeeebbbbuuuugggg command itself).  Otherwise,
                    the debugger is started with the next Tcl
                    statement.

                    The ddddeeeebbbbuuuugggg command does not change any traps.
                    Compare this to starting Expect with the ----DDDD flag
                    (see above).

                    See the README file or SEE ALSO (below) for more
                    information on the debugger.

          ddddiiiissssccccoooonnnnnnnneeeecccctttt
                    disconnects a forked process from the terminal.
                    It continues running in the background.  The
                    process is given its own process group (if
                    possible).  Standard I/O is redirected to
                    /dev/null.

                    The following fragment uses ddddiiiissssccccoooonnnnnnnneeeecccctttt to continue
                    running the script in the background.

                          if [fork]!=0 exit
                          disconnect
                          . . .

                    The following script reads a password, and then
                    runs a program every hour that demands a password
                    each time it is run.  The script supplies the
                    password so that you only have to type it once.
                    (See the ssssttttttttyyyy command which demonstrates how to
                    turn off password echoing.)

                          send_user "password?\ "
                          expect_user -re "(.*)\n"



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                          for {} 1 {} {
                                if [fork]!=0 {sleep 3600;continue}
                                disconnect
                                spawn priv_prog
                                expect Password:
                                send "$expect_out(1,string)\r"
                                . . .
                                exit
                          }

                    An advantage to using ddddiiiissssccccoooonnnnnnnneeeecccctttt over the shell
                    asynchronous process feature (&) is that EEEExxxxppppeeeecccctttt
                    can save the terminal parameters prior to
                    disconnection, and then later apply them to new
                    ptys.  With &, EEEExxxxppppeeeecccctttt does not have a chance to
                    read the terminal's parameters since the terminal
                    is already disconnected by the time EEEExxxxppppeeeecccctttt
                    receives control.

          eeeexxxxiiiitttt [-_o_p_t_s] [_s_t_a_t_u_s]
                    causes EEEExxxxppppeeeecccctttt to exit or otherwise prepare to do
                    so.

                    The ----oooonnnneeeexxxxiiiitttt flag causes the next argument to be
                    used as an exit handler.  Without an argument, the
                    current exit handler is returned.

                    The ----nnnnooooeeeexxxxiiiitttt flag causes EEEExxxxppppeeeecccctttt to prepare to exit
                    but stop short of actually returning control to
                    the operating system.  The user-defined exit
                    handler is run as well as Expect's own internal
                    handlers.  No further Expect commands should be
                    executed.  This is useful if you are running
                    Expect with other Tcl extensions.  The current
                    interpreter (and main window if in the Tk
                    environment) remain so that other Tcl extensions
                    can clean up.  If Expect's eeeexxxxiiiitttt is called again
                    (however this might occur), the handlers are not
                    rerun.

                    Upon exiting, all connections to spawned processes
                    are closed.  Closure will be detected as an EOF by
                    spawned processes.  eeeexxxxiiiitttt takes no other actions
                    beyond what the normal _exit(2) procedure does.
                    Thus, spawned processes that do not check for EOF
                    may continue to run.  (A variety of conditions are
                    important to determining, for example, what
                    signals a spawned process will be sent, but these
                    are system-dependent, typically documented under
                    exit(3).) Spawned processes that continue to run
                    will be inherited by init.




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                    _s_t_a_t_u_s (or 0 if not specified) is returned as the
                    exit status of EEEExxxxppppeeeecccctttt.  eeeexxxxiiiitttt is implicitly
                    executed if the end of the script is reached.

          eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee
                    The command eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee allows eeeexxxxppppeeeecccctttt itself to
                    continue executing rather than returning as it
                    normally would.  (See eeeexxxxppppeeeecccctttt for more
                    information.)



          eeeexxxxpppp____ooooppppeeeennnn [_a_r_g_s] [-_i _s_p_a_w_n__i_d]
                    returns a Tcl file identifier that corresponds to
                    the original spawn id.  The file identifier can
                    then be used as if it were opened by Tcl's ooooppppeeeennnn
                    command.  (The spawn id should no longer be used.
                    A wwwwaaaaiiiitttt should not be executed.

                    The ----lllleeeeaaaavvvveeeeooooppppeeeennnn flag leaves the spawn id open for
                    access through Expect commands.  A wwwwaaaaiiiitttt must be
                    executed on the spawn id.


          eeeexxxxpppp____ppppiiiidddd [-_i _s_p_a_w_n__i_d]
                    returns the process id corresponding to the
                    currently spawned process.  If the ----iiii flag is
                    used, the pid returned corresponds to that of the
                    given spawn id.

          eeeexxxxppppeeeecccctttt [[-_o_p_t_s] _p_a_t_1 _b_o_d_y_1] ... [-_o_p_t_s] _p_a_t_n [_b_o_d_y_n]
                    waits until one of the patterns matches the output
                    of a spawned process, a specified time period has
                    passed, or an end-of-file is seen.  If the final
                    body is empty, it may be omitted.

                    Patterns from the most recent eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee
                    command are implicitly used before any other
                    patterns.  Patterns from the most recent
                    eeeexxxxppppeeeecccctttt____aaaafffftttteeeerrrr command are implicitly used after any
                    other patterns.

                    If the arguments to the entire eeeexxxxppppeeeecccctttt statement
                    require more than one line, all the arguments may
                    be "braced" into one so as to avoid terminating
                    each line with a backslash.  In this one case, the
                    usual Tcl substitutions will occur despite the
                    braces.

                    If a pattern is the keyword eeeeooooffff, the corresponding
                    body is executed upon end-of-file.  If a pattern
                    is the keyword ttttiiiimmmmeeeeoooouuuutttt, the corresponding body is



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                    executed upon timeout.  If no timeout keyword is
                    used, an implicit null action is executed upon
                    timeout.  The default timeout period is 10 seconds
                    but may be set, for example to 30, by the command
                    "set timeout 30".  An infinite timeout may be
                    designated by the value -1.  If a pattern is the
                    keyword ddddeeeeffffaaaauuuulllltttt, the corresponding body is
                    executed upon either timeout or end-of-file.

                    If a pattern matches, then the corresponding body
                    is executed.  eeeexxxxppppeeeecccctttt returns the result of the
                    body (or the empty string if no pattern matched).
                    In the event that multiple patterns match, the one
                    appearing first is used to select a body.

                    Each time new output arrives, it is compared to
                    each pattern in the order they are listed.  Thus,
                    you may test for absence of a match by making the
                    last pattern something guaranteed to appear, such
                    as a prompt.  In situations where there is no
                    prompt, you must use ttttiiiimmmmeeeeoooouuuutttt (just like you would
                    if you were interacting manually).

                    Patterns are specified in three ways.  By default,
                    patterns are specified as with Tcl's ssssttttrrrriiiinnnngggg mmmmaaaattttcccchhhh
                    command.  (Such patterns are also similar to C-
                    shell regular expressions usually referred to as
                    "glob" patterns).  The ----ggggllll flag may may be used to
                    protect patterns that might otherwise match eeeexxxxppppeeeecccctttt
                    flags from doing so.  Any pattern beginning with a
                    "-" should be protected this way.    (All strings
                    starting with "-" are reserved for future
                    options.)


                    For example, the following fragment looks for a
                    successful login.  (Note that aaaabbbboooorrrrtttt is presumed to
                    be a procedure defined elsewhere in the script.)

                          expect {
                                 busy                {print busy\n ; exp_continue}
                                 failed              abort
                                 "invalid password"  abort
                                 timeout             abort
                                 connected
                          }

                    Quotes are necessary on the fourth pattern since
                    it contains a space, which would otherwise
                    separate the pattern from the action.  Patterns
                    with the same action (such as the 3rd and 4th)
                    require listing the actions again.  This can be



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                    avoid by using regexp-style patterns (see below).
                    More information on forming glob-style patterns
                    can be found in the Tcl manual.

                    Regexp-style patterns follow the syntax defined by
                    Tcl's rrrreeeeggggeeeexxxxpppp (short for "regular expression")
                    command.  regexp patterns are introduced with the
                    flag ----rrrreeee.  The previous example can be rewritten
                    using a regexp as:

                          expect {
                                 busy         {print busy\n ; exp_continue}
                                 -re "failed|invalid password" abort
                                 timeout      abort
                                 connected
                          }

                    Both types of patterns are "unanchored".  This
                    means that patterns do not have to match the
                    entire string, but can begin and end the match
                    anywhere in the string (as long as everything else
                    matches).  Use ^ to match the beginning of a
                    string, and $ to match the end.  Note that if you
                    do not wait for the end of a string, your
                    responses can easily end up in the middle of the
                    string as they are echoed from the spawned
                    process.  While still producing correct results,
                    the output can look unnatural.  Thus, use of $ is
                    encouraged if you can exactly describe the
                    characters at the end of a string.

                    Note that in many editors, the ^ and $ match the
                    beginning and end of lines respectively. However,
                    because expect is not line oriented, these
                    characters match the beginning and end of the data
                    (as opposed to lines) currently in the expect
                    matching buffer.  (Also, see the note below on
                    "system indigestion.")

                    The ----eeeexxxx flag causes the pattern to be matched as
                    an "exact" string.  No interpretation of *, ^, etc
                    is made (although the usual Tcl conventions must
                    still be observed).  Exact patterns are always
                    unanchored.


                    The ----nnnnooooccccaaaasssseeee flag causes uppercase characters of
                    the output to compare as if they were lowercase
                    characters.  The pattern is not affected.

                    While reading output, more than 2000 bytes can
                    force earlier bytes to be "forgotten".  This may



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                    be changed with the function mmmmaaaattttcccchhhh____mmmmaaaaxxxx.  (Note
                    that excessively large values can slow down the
                    pattern matcher.) If _p_a_t_l_i_s_t is ffffuuuullllllll____bbbbuuuuffffffffeeeerrrr, the
                    corresponding body is executed if _m_a_t_c_h__m_a_x bytes
                    have been received and no other patterns have
                    matched.  Whether or not the ffffuuuullllllll____bbbbuuuuffffffffeeeerrrr keyword
                    is used, the forgotten characters are written to
                    expect_out(buffer).

                    If _p_a_t_l_i_s_t is the keyword nnnnuuuullllllll, and nulls are
                    allowed (via the rrrreeeemmmmoooovvvveeee____nnnnuuuullllllllssss command), the
                    corresponding body is executed if a single ASCII 0
                    is matched.  It is not possible to match 0 bytes
                    via glob or regexp patterns.

                    Upon matching a pattern (or eof or full_buffer),
                    any matching and previously unmatched output is
                    saved in the variable _e_x_p_e_c_t__o_u_t(_b_u_f_f_e_r).  Up to 9
                    regexp substring matches are saved in the
                    variables _e_x_p_e_c_t__o_u_t(_1,_s_t_r_i_n_g) through
                    _e_x_p_e_c_t__o_u_t(_9,_s_t_r_i_n_g).  If the ----iiiinnnnddddiiiicccceeeessss flag is
                    used before a pattern, the starting and ending
                    indices (in a form suitable for llllrrrraaaannnnggggeeee) of the 10
                    strings are stored in the variables
                    _e_x_p_e_c_t__o_u_t(_X,_s_t_a_r_t) and _e_x_p_e_c_t__o_u_t(_X,_e_n_d) where X
                    is a digit, corresponds to the substring position
                    in the buffer.  0 refers to strings which matched
                    the entired pattern and is generated for glob
                    patterns as well as regexp patterns.  For example,
                    if a process has produced output of "abcdefgh\n",
                    the result of:

                          expect "cd"

                    is as if the following statements had executed:

                                 set expect_out(0,string) cd
                                 set expect_out(buffer) abcd

                    and "efgh\n" is left in the output buffer.  If a
                    process produced the output "abbbcabkkkka\n", the
                    result of:

                                 expect -indices -re "b(b*).*(k+)"

                    is as if the following statements had executed:

                                 set expect_out(0,start) 1
                                 set expect_out(0,end) 10
                                 set expect_out(0,string) bbbcabkkkk
                                 set expect_out(1,start) 2
                                 set expect_out(1,end) 3



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                                 set expect_out(1,string) bb
                                 set expect_out(2,start) 10
                                 set expect_out(2,end) 10
                                 set expect_out(2,string) k
                                 set expect_out(buffer) abbbcabkkkk

                    and "a\n" is left in the output buffer.  The
                    pattern "*" (and -re ".*") will flush the output
                    buffer without reading any more output from the
                    process.

                    Normally, the matched output is discarded from
                    Expect's internal buffers.  This may be prevented
                    by prefixing a pattern with the ----nnnnoooottttrrrraaaannnnssssffffeeeerrrr flag.
                    This flag is especially useful in experimenting
                    (and can be abbreviated to "-n" for convenience
                    while experimenting).

                    The spawn id associated with the matching output
                    (or eof or full_buffer) is stored in
                    _e_x_p_e_c_t__o_u_t(_s_p_a_w_n__i_d).

                    By default, patterns are matched against output
                    from the current process, however the ----iiii flag
                    declares the output from the named spawn_id list
                    be matched against any following patterns (up to
                    the next ----iiii).  The spawn_id list should either be
                    a whitespace separated list of spawn_ids or a
                    variable referring to such a list of spawn_ids.

                    For example, the following example waits for
                    "connected" from the current process, or "busy",
                    "failed" or "invalid password" from the spawn_id
                    named by $proc2.

                          expect {
                                 -i $proc2 busy{print busy\n ; exp_continue}
                                 -re "failed|invalid password" abort
                                 timeout      abort
                                 connected
                          }

                    The value of the global variable _a_n_y__s_p_a_w_n__i_d may
                    be used to match patterns to any spawn_ids that
                    are named with all other ----iiii flags in the current
                    eeeexxxxppppeeeecccctttt command.  The spawn_id from a ----iiii flag with
                    no associated pattern (i.e., followed immediately
                    by another ----iiii) is made available to any other
                    patterns in the same eeeexxxxppppeeeecccctttt command associated
                    with _a_n_y__s_p_a_w_n__i_d.

                    The ----iiii flag may also name a global variable in



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                    which case the variable is read for a list of
                    spawn ids.  The variable is reread whenever it
                    changes.  This provides a way of changing the I/O
                    source while the command is in execution.  Spawn
                    ids provided this way are called "indirect" spawn
                    ids.

                    Actions such as bbbbrrrreeeeaaaakkkk and ccccoooonnnnttttiiiinnnnuuuueeee cause control
                    structures (i.e., ffffoooorrrr, pppprrrroooocccc) to behave in the
                    usual way.  The command eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee allows eeeexxxxppppeeeecccctttt
                    itself to continue executing rather than returning
                    as it normally would.

                    This is useful for avoiding explicit loops or
                    repeated expect statements.  The following example
                    is part of a fragment to automate rlogin.  The
                    eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee avoids having to write a second
                    eeeexxxxppppeeeecccctttt statement (to look for the prompt again) if
                    the rlogin prompts for a password.

                    expect {
                                 Password: {
                                              stty -echo
                                              send_user "password (for $user) on $host: "
                                              expect_user -re "(.*)\n"
                                              send_user "\n"
                                              send "$expect_out(1,string)\r"
                                              stty echo
                                              exp_continue
                                 } incorrect {
                                              send_user "invalid password or account\n"
                                              exit
                                 } timeout {
                                              send_user "connection to $host timed out\n"
                                              exit
                                 } eof {
                                              send_user "connection to host failed: $expect_out(buffer)"
                                              exit
                                 } -re $prompt
                    }

                    For example, the following fragment might help a
                    user guide an interaction that is already totally
                    automated.  In this case, the terminal is put into
                    raw mode.  If the user presses "+", a variable is
                    incremented.  If "p" is pressed, several returns
                    are sent to the process, perhaps to poke it in
                    some way, and "i" lets the user interact with the
                    process, effectively stealing away control from
                    the script.  In each case, the eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee allows
                    the current eeeexxxxppppeeeecccctttt to continue pattern matching
                    after executing the current action.



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                    stty raw -echo
                    expect_after {
                                 -i $user_spawn_id
                                 "p" {send "\r\r\r"; exp_continue}
                                 "+" {incr foo; exp_continue}
                                 "i" {interact; exp_continue}
                                 "quit" exit
                    }


                    By default, eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee resets the timeout timer.
                    The timer is not restarted, if eeeexxxxpppp____ccccoooonnnnttttiiiinnnnuuuueeee is
                    called with the ----ccccoooonnnnttttiiiinnnnuuuueeee____ttttiiiimmmmeeeerrrr flag.

          eeeexxxxppppeeeecccctttt____aaaafffftttteeeerrrr [_e_x_p_e_c_t _a_r_g_s]
                    works identically to the eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee except that
                    if patterns from both eeeexxxxppppeeeecccctttt and eeeexxxxppppeeeecccctttt____aaaafffftttteeeerrrr can
                    match, the eeeexxxxppppeeeecccctttt pattern is used.  See the
                    eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee ccccoooommmmmmmmaaaannnndddd ffffoooorrrr mmmmoooorrrreeee iiiinnnnffffoooorrrrmmmmaaaattttiiiioooonnnn....

          eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd [_e_x_p_e_c_t _a_r_g_s]
                    takes the same arguments as eeeexxxxppppeeeecccctttt, however it
                    returns immediately.  Patterns are tested whenever
                    new input arrives.  Note: this only works in the
                    Tk environment.  The pattern ttttiiiimmmmeeeeoooouuuutttt and ddddeeeeffffaaaauuuulllltttt
                    are meaningless to eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd and are
                    silently discarded.  Otherwise, the
                    eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd command uses eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee and
                    eeeexxxxppppeeeecccctttt____aaaafffftttteeeerrrr patterns just like eeeexxxxppppeeeecccctttt does.

                    When eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd actions are being
                    evaluated, background processing for the same
                    spawn id is blocked.  Background processing is
                    unblocked when the action completes.  While
                    background processing is blocked, it is possible
                    to do a (foreground) eeeexxxxppppeeeecccctttt on the same spawn id.

                    It is not possible to execute an eeeexxxxppppeeeecccctttt while an
                    eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd is unblocked.  eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd
                    for a particular spawn id is deleted by declaring
                    a new expect_background with the same spawn id.
                    Declaring eeeexxxxppppeeeecccctttt____bbbbaaaacccckkkkggggrrrroooouuuunnnndddd with no pattern
                    removes the given spawn id from the ability to
                    match patterns in the background.

          eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee [_e_x_p_e_c_t _a_r_g_s]
                    takes the same arguments as eeeexxxxppppeeeecccctttt, however it
                    returns immediately.  Pattern-action pairs from
                    the most recent eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee with the same spawn
                    id are implicitly added to any following eeeexxxxppppeeeecccctttt
                    commands.  If a pattern matches, it is treated as
                    if it had been specified in the eeeexxxxppppeeeecccctttt command



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                    itself, and the associated body is executed in the
                    context of the eeeexxxxppppeeeecccctttt command.  If patterns from
                    both eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee and eeeexxxxppppeeeecccctttt can match, the
                    eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee pattern is used.

                    If not pattern is specified, the spawn id is not
                    checked for any patterns.

                    Unless overridden by a ----iiii flag, eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee
                    patterns match against the spawn id defined at the
                    time that the eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee command was executed
                    (not when its pattern is matched).

                    The -info flag causes eeeexxxxppppeeeecccctttt____bbbbeeeeffffoooorrrreeee to return the
                    current specifications of what patterns it will
                    match.  By default, it reports on the current
                    spawn id.  An optional spawn id specification may
                    be given for information on that spawn id.  For
                    example

                                 expect_before -info -i $proc

                    At most one spawn id specification may be given.
                    The flag -indirect suppresses direct spawn ids
                    that come only from indirect specifications.

                    Instead of a spawn id specification, the flag "-
                    all" will cause "-info" to report on all spawn
                    ids.

                    The output of the -info flag can be reused as the
                    argument to expect_before.

          eeeexxxxppppeeeecccctttt____ttttttttyyyy [_e_x_p_e_c_t _a_r_g_s]
                    is like eeeexxxxppppeeeecccctttt but it reads characters from
                    /dev/tty (i.e. keystrokes from the user).  By
                    default, reading is performed in cooked mode.
                    Thus, lines must end with a return in order for
                    eeeexxxxppppeeeecccctttt to see them.  This may be changed via ssssttttttttyyyy
                    (see the ssssttttttttyyyy command below).

          eeeexxxxppppeeeecccctttt____uuuusssseeeerrrr [_e_x_p_e_c_t _a_r_g_s]
                    is like eeeexxxxppppeeeecccctttt but it reads characters from stdin
                    (i.e. keystrokes from the user).  By default,
                    reading is performed in cooked mode.  Thus, lines
                    must end with a return in order for eeeexxxxppppeeeecccctttt to see
                    them.  This may be changed via ssssttttttttyyyy (see the ssssttttttttyyyy
                    command below).

          eeeexxxxpppp____vvvveeeerrrrssssiiiioooonnnn [[-_e_x_i_t] _v_e_r_s_i_o_n]
                    is useful for assuring that the script is
                    compatible with the current version of Expect.



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                    With no arguments, the current version of EEEExxxxppppeeeecccctttt
                    is returned.  This version may then be encoded in
                    your script.  If you actually know that you are
                    not using features of recent versions, you can
                    specify an earlier version.

                    Versions consist of three numbers separated by
                    dots.  First is the major number.  Scripts written
                    for versions of EEEExxxxppppeeeecccctttt with a different major
                    number will almost certainly not work.
                    eeeexxxxpppp____vvvveeeerrrrssssiiiioooonnnn returns an error if the major numbers
                    do not match.

                    Second is the minor number.  Scripts written for a
                    version with a greater minor number than the
                    current version may depend upon some new feature
                    and might not run.  eeeexxxxpppp____vvvveeeerrrrssssiiiioooonnnn returns an error
                    if the major numbers match, but the script minor
                    number is greater than that of the running EEEExxxxppppeeeecccctttt.

                    Third is a number that plays no part in the
                    version comparison.  However, it is incremented
                    when the EEEExxxxppppeeeecccctttt software distribution is changed
                    in any way, such as by additional documentation or
                    optimization.  It is reset to 0 upon each new
                    minor version.

                    With the ----eeeexxxxiiiitttt flag, EEEExxxxppppeeeecccctttt prints an error and
                    exits if the version is out of date.

          ffffoooorrrrkkkk      creates a new process.  The new process is an
                    exact copy of the current EEEExxxxppppeeeecccctttt process.  On
                    success, ffffoooorrrrkkkk returns 0 to the new (child) process
                    and returns the process ID of the child process to
                    the parent process.  On failure (invariably due to
                    lack of resources, e.g., swap space, memory), ffffoooorrrrkkkk
                    returns -1 to the parent process, and no child
                    process is created.

                    Forked processes exit via the eeeexxxxiiiitttt command, just
                    like the original process.  Forked processes are
                    allowed to write to the log files.  If you do not
                    disable debugging or logging in most of the
                    processes, the result can be confusing.

                    Some pty implementations may be confused by
                    multiple readers and writers, even momentarily.
                    Thus, it is safest to ffffoooorrrrkkkk before spawning
                    processes.

          iiiinnnntttteeeerrrraaaacccctttt [_s_t_r_i_n_g_1 _b_o_d_y_1] ... [_s_t_r_i_n_g_n [_b_o_d_y_n]]
                    gives control of the current process to the user,



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                    so that keystrokes are sent to the current
                    process, and the stdout and stderr of the current
                    process are returned.

                    String-body pairs may be specified as arguments,
                    in which case the body is executed when the
                    corresponding string is entered.  (By default, the
                    string is not sent to the current process.)   The
                    iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr command is assumed, if the final body
                    is missing.

                    If the arguments to the entire iiiinnnntttteeeerrrraaaacccctttt statement
                    require more than one line, all the arguments may
                    be "braced" into one so as to avoid terminating
                    each line with a backslash.  In this one case, the
                    usual Tcl substitutions will occur despite the
                    braces.

                    For example, the following command runs interact
                    with the following string-body pairs defined:
                    When ^Z is pressed, EEEExxxxppppeeeecccctttt is suspended.  (The
                    ----rrrreeeesssseeeetttt flag restores the terminal modes.) When ^A
                    is pressed, the user sees "you typed a control-A"
                    and the process is sent a ^A.  When $ is pressed,
                    the user sees the date.  When ^C is pressed,
                    EEEExxxxppppeeeecccctttt exits.  If "foo" is entered, the user sees
                    "bar".  When ~~ is pressed, the EEEExxxxppppeeeecccctttt interpreter
                    runs interactively.

                        set CTRLZ \032
                        interact {
                                 -reset $CTRLZ {exec kill -STOP [pid]}
                                 \001    {send_user "you typed a control-A\n";
                                          send "\001"
                                         }
                                 $       {send_user "The date is [exec date]."}
                                 \003    exit
                                 foo     {send_user "bar"}
                                 ~~
                        }


                    In string-body pairs, strings are matched in the
                    order they are listed as arguments.  Strings that
                    partially match are not sent to the current
                    process in anticipation of the remainder coming.
                    If characters are then entered such that there can
                    no longer possibly be a match, only the part of
                    the string will be sent to the process that cannot
                    possibly begin another match.  Thus, strings that
                    are substrings of partial matches can match later,
                    if the original strings that was attempting to be



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                    match ultimately fails.

                    By default, string matching is exact with no wild
                    cards.  (In contrast, the eeeexxxxppppeeeecccctttt command uses
                    glob-style patterns by default.)  The ----eeeexxxx flag may
                    be used to protect patterns that might otherwise
                    match iiiinnnntttteeeerrrraaaacccctttt flags from doing so.  Any pattern
                    beginning with a "-" should be protected this way.
                    (All strings starting with "-" are reserved for
                    future options.)

                    The ----rrrreeee flag forces the string to be interpreted
                    as a regexp-style pattern.  In this case, matching
                    substrings are stored in the variable _i_n_t_e_r_a_c_t__o_u_t
                    similarly to the way eeeexxxxppppeeeecccctttt stores its output in
                    the variable eeeexxxxppppeeeecccctttt____oooouuuutttt.  The ----iiiinnnnddddiiiicccceeeessss flag is
                    similarly supported.

                    The pattern eeeeooooffff introduces an action that is
                    executed upon end-of-file.  A separate eeeeooooffff pattern
                    may also follow the ----oooouuuuttttppppuuuutttt flag in which case it
                    is matched if an eof is detected while writing
                    output.  The default eeeeooooffff action is "return", so
                    that iiiinnnntttteeeerrrraaaacccctttt simply returns upon any EOF.

                    The pattern ttttiiiimmmmeeeeoooouuuutttt introduces a timeout (in
                    seconds) and action that is executed after no
                    characters have been read for a given time.  The
                    ttttiiiimmmmeeeeoooouuuutttt pattern applies to the most recently
                    specified process.  There is no default timeout.
                    The special variable "timeout" (used by the eeeexxxxppppeeeecccctttt
                    command) has no affect on this timeout.

                    For example, the following statement could be used
                    to autologout users who have not typed anything
                    for an hour but who still get frequent system
                    messages:

                                 interact -input $user_spawn_id timeout 3600 return -output $spawn_id


                    If the pattern is the keyword nnnnuuuullllllll, and nulls are
                    allowed (via the rrrreeeemmmmoooovvvveeee____nnnnuuuullllllllssss command), the
                    corresponding body is executed if a single ASCII 0
                    is matched.  It is not possible to match 0 bytes
                    via glob or regexp patterns.

                    Prefacing a pattern with the flag ----iiiiwwwwrrrriiiitttteeee causes
                    the variable _i_n_t_e_r_a_c_t__o_u_t(_s_p_a_w_n__i_d) to be set to
                    the spawn_id which matched the pattern (or eof).

                    Actions such as bbbbrrrreeeeaaaakkkk and ccccoooonnnnttttiiiinnnnuuuueeee cause control



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                    structures (i.e., ffffoooorrrr, pppprrrroooocccc) to behave in the
                    usual way.  However rrrreeeettttuuuurrrrnnnn causes interact to
                    return to its caller, while iiiinnnntttteeeerrrr____rrrreeeettttuuuurrrrnnnn causes
                    iiiinnnntttteeeerrrraaaacccctttt to cause a return in its caller.  For
                    example, if "proc foo" called iiiinnnntttteeeerrrraaaacccctttt which then
                    executed the action iiiinnnntttteeeerrrr____rrrreeeettttuuuurrrrnnnn, pppprrrroooocccc ffffoooooooo would
                    return.  (This means that if iiiinnnntttteeeerrrraaaacccctttt calls
                    iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr interactively typing rrrreeeettttuuuurrrrnnnn will cause
                    the interact to continue, while iiiinnnntttteeeerrrr____rrrreeeettttuuuurrrrnnnn will
                    cause the interact to return to its caller.)

                    During iiiinnnntttteeeerrrraaaacccctttt, raw mode is used so that all
                    characters may be passed to the current process.
                    If the current process does not catch job control
                    signals, it will stop if sent a stop signal (by
                    default ^Z).  To restart it, send a continue
                    signal (such as by "kill -CONT <pid>").  If you
                    really want to send a SIGSTOP to such a process
                    (by ^Z), consider spawning csh first and then
                    running your program.  On the other hand, if you
                    want to send a SIGSTOP to EEEExxxxppppeeeecccctttt itself, first
                    press the escape character, and then press ^Z.

                    String-body pairs can be used as a shorthand for
                    avoiding having to enter the interpreter and
                    execute commands interactively.  The previous
                    terminal mode is used while the body of a string-
                    body pair is being executed.

                    For speed, actions execute in raw mode by default.
                    The ----rrrreeeesssseeeetttt flag resets the terminal to the mode it
                    had before iiiinnnntttteeeerrrraaaacccctttt was executed (invariably,
                    cooked mode).  Note that characters entered when
                    the mode is being switched may be lost (an
                    unfortunate feature of the terminal driver on some
                    systems).  The only reason to use ----rrrreeeesssseeeetttt is if
                    your action depends on running in cooked mode.

                    The ----eeeecccchhhhoooo flag sends characters that match the
                    following pattern back to the process that
                    generated them as each character is read.  This
                    may be useful when the user needs to see feedback
                    from partially typed patterns.

                    If a pattern is being echoed but eventually fails
                    to match, the characters are sent to the spawned
                    process.  If the spawned process then echoes them,
                    the user will see the characters twice.  ----eeeecccchhhhoooo is
                    probably only appropriate in situations where the
                    user is unlikely to not complete the pattern.  For
                    example, the following excerpt is from rftp, the
                    recursive-ftp script, where the user is prompted



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                    to enter ~g, ~p, or ~l, to get, put, or list the
                    current directory recursively.  These are so far
                    away from the normal ftp commands, that the user
                    is unlikely to type ~ followed by anything else,
                    except mistakenly, in which case, they'll probably
                    just ignore the result anyway.

                        interact {
                                 -echo ~g {getcurdirectory 1}
                                 -echo ~l {getcurdirectory 0}
                                 -echo ~p {putcurdirectory}
                        }

                    The ----nnnnoooobbbbuuuuffffffffeeeerrrr flag sends characters that match the
                    following pattern on to the output process as
                    characters are read.

                    This is useful when you wish to let a program echo
                    back the pattern.  For example, the following
                    might be used to monitor where a person is dialing
                    (a Hayes-style modem).  Each time "atd" is seen
                    the script logs the rest of the line.

                        proc lognumber {} {
                            interact -nobuffer -re "(.*)" return
                            puts $log "[exec date]: dialed $interact_out(1,string)"
                        }

                        interact -nobuffer "atd" lognumber


                    During iiiinnnntttteeeerrrraaaacccctttt, previous use of lllloooogggg____uuuusssseeeerrrr is
                    ignored.  In particular, iiiinnnntttteeeerrrraaaacccctttt will force its
                    output to be logged (sent to the standard output)
                    since it is presumed the user doesn't wish to
                    interact blindly.

                    The ----oooo flag causes any following key-body pairs to
                    be applied to the output of the current process.
                    This can be useful, for example, when dealing with
                    hosts that send unwanted characters during a
                    telnet session.

                    By default, iiiinnnntttteeeerrrraaaacccctttt expects the user to be
                    writing stdin and reading stdout of the EEEExxxxppppeeeecccctttt
                    process itself.  The ----uuuu flag (for "user") makes
                    iiiinnnntttteeeerrrraaaacccctttt look for the user as the process named by
                    its argument (which must be a spawned id).

                    This allows two unrelated processes to be joined
                    together without using an explicit loop.  To aid
                    in debugging, Expect diagnostics always go to



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                    stderr (or stdout for certain logging and
                    debugging information).  For the same reason, the
                    iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr command will read interactively from
                    stdin.

                    For example, the following fragment creates a
                    login process.  Then it dials the user (not
                    shown), and finally connects the two together.  Of
                    course, any process may be substituted for login.
                    A shell, for example, would allow the user to work
                    without supplying an account and password.

                        spawn login
                        set login $spawn_id
                        spawn tip modem
                        # dial back out to user
                        # connect user to login
                        interact -u $login

                    To send output to multiple processes, list each
                    spawn id list prefaced by a ----oooouuuuttttppppuuuutttt flag.  Input
                    for a group of output spawn ids may be determined
                    by a spawn id list prefaced by a ----iiiinnnnppppuuuutttt flag.
                    (Both ----iiiinnnnppppuuuutttt and ----oooouuuuttttppppuuuutttt may take lists in the
                    same form as the ----iiii flag in the eeeexxxxppppeeeecccctttt command,
                    except that any_spawn_id is not meaningful in
                    iiiinnnntttteeeerrrraaaacccctttt.) All following flags and strings (or
                    patterns) apply to this input until another -input
                    flag appears.  If no ----iiiinnnnppppuuuutttt appears, ----oooouuuuttttppppuuuutttt
                    implies "-input $user_spawn_id -output".
                    (Similarly, with patterns that do not have
                    ----iiiinnnnppppuuuutttt.) If one ----iiiinnnnppppuuuutttt is specified, it overrides
                    $user_spawn_id.  If a second ----iiiinnnnppppuuuutttt is specified,
                    it overrides $spawn_id.  Additional ----iiiinnnnppppuuuutttt flags
                    may be specified.

                    The two implied input processes default to having
                    their outputs specified as $spawn_id and
                    $user_spawn_id (in reverse). If a ----iiiinnnnppppuuuutttt flag
                    appears with no ----oooouuuuttttppppuuuutttt flag, characters from that
                    process are discarded.

                    The ----iiii flag introduces a replacement for the
                    current spawn_id when no other ----iiiinnnnppppuuuutttt or ----oooouuuuttttppppuuuutttt
                    flags are used.

                    It is possible to change the processes that are
                    being interacted with by using indirect spawn ids.
                    (Indirect spawn ids are described in the section
                    on the expect command.)  Indirect spawn ids may be
                    specified with the -i, -u, -input, or -output
                    flags.



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          eeeexxxxpppp____iiiinnnntttteeeerrrrnnnnaaaallll [-_f _f_i_l_e] _v_a_l_u_e
                    causes further commands to send diagnostic
                    information internal to EEEExxxxppppeeeecccctttt to stderr if _v_a_l_u_e
                    is non-zero.  This output is disabled if _v_a_l_u_e is
                    0.  The diagnostic information includes every
                    character received, and every attempt made to
                    match the current output against the patterns.

                    If the optional _f_i_l_e is supplied, all normal and
                    debugging output is written to that file
                    (regardless of the value of _v_a_l_u_e).  Any previous
                    diagnostic output file is closed.

                    The ----iiiinnnnffffoooo flag causes exp_internal to return a
                    description of the most recent non-info arguments
                    given.

          iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr
                    causes the user to be interactively prompted for
                    EEEExxxxppppeeeecccctttt and Tcl commands.  The result of each
                    command is printed.

                    Actions such as bbbbrrrreeeeaaaakkkk and ccccoooonnnnttttiiiinnnnuuuueeee cause control
                    structures (i.e., ffffoooorrrr, pppprrrroooocccc) to behave in the
                    usual way.  However rrrreeeettttuuuurrrrnnnn causes interpreter to
                    return to its caller, while iiiinnnntttteeeerrrr____rrrreeeettttuuuurrrrnnnn causes
                    iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr to cause a return in its caller.  For
                    example, if "proc foo" called iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr which
                    then executed the action iiiinnnntttteeeerrrr____rrrreeeettttuuuurrrrnnnn, pppprrrroooocccc ffffoooooooo
                    would return.  Any other command causes
                    iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr to continue prompting for new
                    commands.

                    By default, the prompt contains two integers.  The
                    first integer describes the depth of the
                    evaluation stack (i.e., how many times Tcl_Eval
                    has been called).  The second integer is the Tcl
                    history identifier.  The prompt can be set by
                    defining a procedure called "prompt1" whose return
                    value becomes the next prompt.  If a statement has
                    open quotes, parens, braces, or brackets, a
                    secondary prompt (by default "+> ") is issued upon
                    newline.  The secondary prompt may be set by
                    defining a procedure called "prompt2".

                    During iiiinnnntttteeeerrrrpppprrrreeeetttteeeerrrr, cooked mode is used, even if
                    the its caller was using raw mode.

          lllloooogggg____ffffiiiilllleeee [_a_r_g_s] [[-_a] _f_i_l_e]
                    If a filename is provided, lllloooogggg____ffffiiiilllleeee will record a
                    transcript of the session (beginning at that
                    point) in the file.  lllloooogggg____ffffiiiilllleeee will stop recording



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                    if no argument is given.  Any previous log file is
                    closed.

                    Instead of a filename, a Tcl file identifier may
                    be provided by using the ----ooooppppeeeennnn or ----lllleeeeaaaavvvveeeeooooppppeeeennnn
                    flags.  This is similar to the ssssppppaaaawwwwnnnn command.
                    (See ssssppppaaaawwwwnnnn for more info.)

                    The ----aaaa flag forces output to be logged that was
                    suppressed by the lllloooogggg____uuuusssseeeerrrr command.

                    By default, the lllloooogggg____ffffiiiilllleeee command _a_p_p_e_n_d_s to old
                    files rather than truncating them, for the
                    convenience of being able to turn logging off and
                    on multiple times in one session.  To truncate
                    files, use the ----nnnnooooaaaappppppppeeeennnndddd ffffllllaaaagggg....

                    The ----iiiinnnnffffoooo flag causes log_file to return a
                    description of the most recent non-info arguments
                    given.

          lllloooogggg____uuuusssseeeerrrr _0|_1
                    By default, the send/expect dialogue is logged to
                    stdout (and a logfile if open).  The logging to
                    stdout is disabled by the command "log_user 0" and
                    reenabled by "log_user 1".  Logging to the logfile
                    is unchanged.

                    The ----iiiinnnnffffoooo flag causes log_user to return a
                    description of the most recent non-info arguments
                    given.


          mmmmaaaattttcccchhhh____mmmmaaaaxxxx [-_d] [-_i _s_p_a_w_n__i_d] [_s_i_z_e]
                    defines the size of the buffer (in bytes) used
                    internally by eeeexxxxppppeeeecccctttt.  With no _s_i_z_e argument, the
                    current size is returned.

                    With the ----dddd flag, the default size is set.  (The
                    initial default is 2000.) With the ----iiii flag, the
                    size is set for the named spawn id, otherwise it
                    is set for the current process.

          oooovvvveeeerrrrllllaaaayyyy [-# _s_p_a_w_n__i_d] [-# _s_p_a_w_n__i_d] [...] _p_r_o_g_r_a_m [_a_r_g_s]
                    executes _p_r_o_g_r_a_m _a_r_g_s in place of the current
                    EEEExxxxppppeeeecccctttt program, which terminates.  A bare hyphen
                    argument forces a hyphen in front of the command
                    name as if it was a login shell.  All spawn_ids
                    are closed except for those named as arguments.
                    These are mapped onto the named file identifiers.

                    Spawn_ids are mapped to file identifiers for the



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                    new program to inherit.  For example, the
                    following line runs chess and allows it to be
                    controlled by the current process - say, a chess
                    master.

                                 overlay -0 $spawn_id -1 $spawn_id -2 $spawn_id chess

                    This is more efficient than "interact -u",
                    however, it sacrifices the ability to do
                    programmed interaction since the EEEExxxxppppeeeecccctttt process is
                    no longer in control.

                    Note that no controlling terminal is provided.
                    Thus, if you disconnect or remap standard input,
                    programs that do job control (shells, login, etc)
                    will not function properly.

          ppppaaaarrrriiiittttyyyy [-_d] [-_i _s_p_a_w_n__i_d] [_v_a_l_u_e]
                    defines whether parity should be retained or
                    stripped from the output of spawned processes.  If
                    _v_a_l_u_e is zero, parity is stripped, otherwise it is
                    not stripped.  With no _v_a_l_u_e argument, the current
                    value is returned.

                    With the ----dddd flag, the default parity value is set.
                    (The initial default is 1, i.e., parity is not
                    stripped.) With the ----iiii flag, the parity value is
                    set for the named spawn id, otherwise it is set
                    for the current process.

          eeeexxxxpppp____ppppiiiidddd [-_i _s_p_a_w_n__i_d]
                    returns the process id corresponding to the
                    current spawn id or the named spawn id.

          rrrreeeemmmmoooovvvveeee____nnnnuuuullllllllssss [-_d] [-_i _s_p_a_w_n__i_d] [_v_a_l_u_e]
                    defines whether nulls are retained or removed from
                    the output of spawned processes before pattern
                    matching or storing in the variable _e_x_p_e_c_t__o_u_t or
                    _i_n_t_e_r_a_c_t__o_u_t.  If _v_a_l_u_e is 1, nulls are removed.
                    If _v_a_l_u_e is 0, nulls are not removed.  With no
                    _v_a_l_u_e argument, the current value is returned.

                    With the ----dddd flag, the default value is set.  (The
                    initial default is 1, i.e., nulls are removed.)
                    With the ----iiii flag, the value is set for the named
                    spawn id, otherwise it is set for the current
                    process.

                    Whether or not nulls are removed, EEEExxxxppppeeeecccctttt will
                    record null bytes to the log and stdout.

          sssseeeennnndddd [-_f_l_a_g_s] _s_t_r_i_n_g



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                    Sends _s_t_r_i_n_g to the current process.  For example,
                    the command

                                 send "hello world\r"

                    sends the characters, h e l l o <blank> w o r l d
                    <return> to the current process. (Tcl includes a
                    printf-like command (called ffffoooorrrrmmmmaaaatttt) which can
                    build arbitrarily complex strings.)

                    Characters are sent immediately although programs
                    with line-buffered input will not read the
                    characters until a return character is sent.  A
                    return character is denoted "\r".

                    The -------- flag forces the next argument to be
                    interpreted as a string rather than a flag.  Any
                    string can be preceded by "--" whether or not it
                    actually looks like a flag.  This provides a
                    reliable mechanism to specify variable strings
                    without being tripped up by those that
                    accidentally look like flags.  (All strings
                    starting with "-" are reserved for future
                    options.)

                    The ----iiii flag declares that the string be sent to
                    the named spawn_id.  If the spawn_id is
                    _u_s_e_r__s_p_a_w_n__i_d, and the terminal is in raw mode,
                    newlines in the string are translated to return-
                    newline sequences so that they appear as it the
                    terminal was in cooked mode.  The ----rrrraaaawwww flag
                    disables this translation.

                    The ----nnnnuuuullllllll flag sends null characters (0 bytes).
                    By default, one null is sent.  An integer may
                    follow the ----0000 to indicate how many nulls to send.

                    The ----bbbbrrrreeeeaaaakkkk flag generates a break condition.  This
                    only makes sense if the spawn id refers to a tty
                    device opened via "spawn -open".  If you have
                    spawned a process such as tip, you should use
                    tip's convention for generating a break.

                    The ----ssss flag forces output to be sent "slowly",
                    thus avoid the common situation where a computer
                    outtypes an input buffer that was designed for a
                    human who would never outtype the same buffer.
                    This output is controlled by the value of the
                    variable "send_slow" which takes a two element
                    list.  The first element is an integer that
                    describes the number of bytes to send atomically.
                    The second element is a real number that describes



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                    the number of seconds by which the atomic sends
                    must be separated.  For example, "set send_slow
                    {10 .001}" would force "send -s" to send strings
                    with 1 millisecond in between each 10 characters
                    sent.

                    The ----hhhh flag forces output to be sent (somewhat)
                    like a human actually typing.  Human-like delays
                    appear between the characters.  (The algorithm is
                    based upon a Weibull distribution, with
                    modifications to suit this particular
                    application.)  This output is controlled by the
                    value of the variable "send_human" which takes a
                    five element list.  The first two elements are
                    average interarrival time of characters in
                    seconds.  The first is used by default.  The
                    second is used at word endings, to simulate the
                    subtle pauses that occasionally occur at such
                    transitions.  The third parameter is a measure of
                    varibility where .1 is quite variable, 1 is
                    reasonably variable, and 10 is quite invariable.
                    The extremes are 0 to infinity.  The last two
                    parameters are, respectively, a minimum and
                    maximum interarrival time.  The minimum and
                    maximum are used last and "clip" the final time.
                    The ultimate average can be quite different from
                    the given average if the minimum and miximum clip
                    enough values.

                    As an example, the following command emulates a
                    fast and consistent typist:

                                 set send_human {.1 .3 1 .05 2}
                                 send -h "I'm hungry.  Let's do lunch."

                    while the following might be more suitable after a
                    hangover:

                                 set send_human {.4 .4 .2 .5 100}
                                 send -h "Goodd party lash night!"

                    Note that errors are not simulated, although you
                    can set up error correction situations yourself by
                    embedding mistakes and corrections in a send
                    argument.

                    It is a good idea to precede the first sssseeeennnndddd to a
                    process by an eeeexxxxppppeeeecccctttt.  eeeexxxxppppeeeecccctttt will wait for the
                    process to start, while sssseeeennnndddd cannot.  In
                    particular, if the first sssseeeennnndddd completes before the
                    process starts running, you run the risk of having
                    your data ignored.  In situations where



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                    interactive programs offer no initial prompt, you
                    can precede sssseeeennnndddd by a delay as in:

                                 # To avoid giving hackers hints on how to break in,
                                 # this system does not prompt for an external password.
                                 # Wait for 5 seconds for exec to complete
                                 spawn telnet very.secure.gov
                                 sleep 5
                                 send password\r

                    eeeexxxxpppp____sssseeeennnndddd is an alias for sssseeeennnndddd.  If you are using
                    Expectk or some other variant of Expect in the Tk
                    environment, sssseeeennnndddd is defined by Tk for an entirely
                    different purpose.  eeeexxxxpppp____sssseeeennnndddd is provided for
                    compatibility between environments.  Similar
                    aliases are provided for other Expect's other send
                    commands.

          sssseeeennnndddd____eeeerrrrrrrroooorrrr _s_t_r_i_n_g
                    is like sssseeeennnndddd, except that the string is sent to
                    stderr rather than the current process.

          sssseeeennnndddd____lllloooogggg _s_t_r_i_n_g
                    is like sssseeeennnndddd, except that the string is only sent
                    to the log file (see lllloooogggg____ffffiiiilllleeee.) The arguments are
                    ignored if no log file is open.

          sssseeeennnndddd____ttttttttyyyy _s_t_r_i_n_g
                    is like sssseeeennnndddd, except that the string is sent to
                    /dev/tty rather than the current process.

          sssseeeennnndddd____uuuusssseeeerrrr [_a_r_g_s] _s_t_r_i_n_g
                    is like sssseeeennnndddd, except that the arguments are sent
                    to stdout rather than the current process.

          sssslllleeeeeeeepppp_s_e_c_o_n_d_s
                    causes the script to sleep for the given number of
                    seconds.  Seconds may be a decimal number.
                    Interrupts (and Tk events if you are using
                    Expectk) are processed while Expect sleeps.

          ssssppppaaaawwwwnnnn [_a_r_g_s] _p_r_o_g_r_a_m [_a_r_g_s]
                    creates a new process running _p_r_o_g_r_a_m _a_r_g_s.  Its
                    stdin, stdout and stderr are connected to Expect,
                    so that they may be read and written by other
                    EEEExxxxppppeeeecccctttt commands.  The connection is broken by
                    cccclllloooosssseeee or if the process itself closes any of the
                    file identifiers.

                    When a process is started by ssssppppaaaawwwwnnnn, the variable
                    _s_p_a_w_n__i_d is set to a descriptor referring to that
                    process.  The process described by _s_p_a_w_n__i_d is



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                    considered the _c_u_r_r_e_n_t _p_r_o_c_e_s_s.  _s_p_a_w_n__i_d may be
                    read or written, in effect providing job control.

                    _u_s_e_r__s_p_a_w_n__i_d is a global variable containing a
                    descriptor which refers to the user.  For example,
                    when _s_p_a_w_n__i_d is set to this value, eeeexxxxppppeeeecccctttt behaves
                    like eeeexxxxppppeeeecccctttt____uuuusssseeeerrrr.

                    _e_r_r_o_r__s_p_a_w_n__i_d is a global variable containing a
                    descriptor which refers to the standard error.
                    For example, when _s_p_a_w_n__i_d is set to this value,
                    sssseeeennnndddd behaves like sssseeeennnndddd____eeeerrrrrrrroooorrrr.


                    _t_t_y__s_p_a_w_n__i_d is a global variable containing a
                    descriptor which refers to /dev/tty.  If /dev/tty
                    does not exist (such as in a cron, at, or batch
                    script), then _t_t_y__s_p_a_w_n__i_d is not defined.  This
                    may be tested as:

                                 if [info vars tty_spawn_id] {
                                         # /dev/tty exists
                                 } else {
                                         # /dev/tty doesn't exist
                                         # probably in cron, batch, or at script
                                 }


                    ssssppppaaaawwwwnnnn returns the UNIX process id.  If no process
                    is spawned, 0 is returned.  The variable
                    _s_p_a_w_n__o_u_t(_s_l_a_v_e,_n_a_m_e) is set to the name of the
                    pty slave device.


                    By default, ssssppppaaaawwwwnnnn echoes the command name and
                    arguments.  The ----nnnnooooeeeecccchhhhoooo flag stops ssssppppaaaawwwwnnnn from
                    doing this.

                    The ----ccccoooonnnnssssoooolllleeee flag causes console output to be
                    redirected to the spawned process.  This is not
                    supported on all systems.

                    Internally, ssssppppaaaawwwwnnnn uses a pty, initialized the same
                    way as the user's tty.  This is further
                    initialized so that all settings are "sane"
                    (according to stty(1)).  If the variable _s_t_t_y__i_n_i_t
                    is defined, it is interpreted in the style of stty
                    arguments as further configuration.  For example,
                    "set stty_init raw" will cause further spawned
                    processes's terminals to start in raw mode.
                    ----nnnnoooottttttttyyyyccccooooppppyyyy skips the initialization based on the
                    user's tty.  ----nnnnoooottttttttyyyyiiiinnnniiiitttt skips the "sane"



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                    initialization.

                    Normally, ssssppppaaaawwwwnnnn takes little time to execute.  If
                    you notice spawn taking a significant amount of
                    time, it is probably encountering ptys that are
                    wedged.  A number of tests are run on ptys to
                    avoid entanglements with errant processes.  (These
                    take 10 seconds per wedged pty.)  Running Expect
                    with the ----dddd option will show if EEEExxxxppppeeeecccctttt is
                    encountering many ptys in odd states.  If you
                    cannot kill the processes to which these ptys are
                    attached, your only recourse may be to reboot.

                    If _p_r_o_g_r_a_m cannot be spawned successfully because
                    exec(2) fails (e.g. when _p_r_o_g_r_a_m doesn't exist),
                    an error message will be returned by the next
                    iiiinnnntttteeeerrrraaaacccctttt or eeeexxxxppppeeeecccctttt command as if _p_r_o_g_r_a_m had run
                    and produced the error message as output.  This
                    behavior is a natural consequence of the
                    implementation of ssssppppaaaawwwwnnnn.  Internally, spawn forks,
                    after which the spawned process has no way to
                    communicate with the original EEEExxxxppppeeeecccctttt process
                    except by communication via the spawn_id.

                    The ----ooooppppeeeennnn flag causes the next argument to be
                    interpreted as a Tcl file identifier (i.e.,
                    returned by ooooppppeeeennnn.) The spawn id can then be used
                    as if it were a spawned process.  (The file
                    identifier should no longer be used.) This lets
                    you treat raw devices, files, and pipelines as
                    spawned processes without using a pty.  0 is
                    returned to indicate there is no associated
                    process.  When the connection to the spawned
                    process is closed, so is the Tcl file identifier.
                    The ----lllleeeeaaaavvvveeeeooooppppeeeennnn flag is similar to ----ooooppppeeeennnn except
                    that ----lllleeeeaaaavvvveeeeooooppppeeeennnn causes the file identifier to be
                    left open even after the spawn id is closed.

                    The ----ppppttttyyyy flag causes a pty to be opened but no
                    process spawned.  0 is returned to indicate there
                    is no associated process.  Spawn_id is set as
                    usual.

                    The variable _s_p_a_w_n__o_u_t(_s_l_a_v_e,_f_d) is set to a file
                    identifier corresponding to the pty slave.  It can
                    be closed using "close -slave".

                    The ----iiiiggggnnnnoooorrrreeee flag names a signal to be ignored in
                    the spawned process.  Otherwise, signals get the
                    default behavior.  Signals are named as in the
                    ttttrrrraaaapppp command, except that each signal requires a
                    separate flag.



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          ssssttttrrrraaaacccceeee _l_e_v_e_l
                    causes following statements to be printed before
                    being executed.  (Tcl's trace command traces
                    variables.) _l_e_v_e_l indicates how far down in the
                    call stack to trace.  For example, the following
                    command runs EEEExxxxppppeeeecccctttt while tracing the first 4
                    levels of calls, but none below that.

                                 expect -c "strace 4" script.exp


                    The ----iiiinnnnffffoooo flag causes strace to return a
                    description of the most recent non-info arguments
                    given.

          ssssttttttttyyyy _a_r_g_s changes terminal modes similarly to the external
                    stty command.

                    By default, the controlling terminal is accessed.
                    Other terminals can be accessed by appending "<
                    /dev/tty..." to the command.  (Note that the
                    arguments should not be grouped into a single
                    argument.)

                    Requests for status return it as the result of the
                    command.  If no status is requested and the
                    controlling terminal is accessed, the previous
                    status of the raw and echo attributes are returned
                    in a form which can later be used by the command.

                    For example, the arguments rrrraaaawwww or ----ccccooooooookkkkeeeedddd put the
                    terminal into raw mode.  The arguments ----rrrraaaawwww or
                    ccccooooooookkkkeeeedddd put the terminal into cooked mode.  The
                    arguments eeeecccchhhhoooo and ----eeeecccchhhhoooo put the terminal into
                    echo and noecho mode respectively.

                    The following example illustrates how to
                    temporarily disable echoing.  This could be used
                    in otherwise-automatic scripts to avoid embedding
                    passwords in them.  (See more discussion on this
                    under EXPECT HINTS below.)

                                 stty -echo
                                 send_user "Password: "
                                 expect_user -re "(.*)\n"
                                 set password $expect_out(1,string)
                                 stty echo


          ssssyyyysssstttteeeemmmm _a_r_g_s
                    gives _a_r_g_s to sh(1) as input, just as if it had
                    been typed as a command from a terminal.  EEEExxxxppppeeeecccctttt



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                    waits until the shell terminates.  The return
                    status from sh is handled the same way that eeeexxxxeeeecccc
                    handles its return status.

                    In contrast to eeeexxxxeeeecccc which redirects stdin and
                    stdout to the script, ssssyyyysssstttteeeemmmm performs no
                    redirection (other than that indicated by the
                    string itself).  Thus, it is possible to use
                    programs which must talk directly to /dev/tty.
                    For the same reason, the results of ssssyyyysssstttteeeemmmm are not
                    recorded in the log.

          ttttiiiimmmmeeeessssttttaaaammmmpppp [_a_r_g_s]
                    returns a timestamp.  With no arguments, the
                    number of seconds since the epoch is returned.

                    The ----ffffoooorrrrmmmmaaaatttt flag introduces a string which is
                    returned but with substitutions made according to
                    the POSIX rules for strftime.  For example %a is
                    replaced by an abbreviated weekday name (i.e.,
                    Sat).  Others are:
                                 %a      abbreviated weekday name
                                 %A      full weekday name
                                 %b      abbreviated month name
                                 %B      full month name
                                 %c      date-time as in: Wed Oct  6 11:45:56 1993
                                 %d      day of the month (01-31)
                                 %H      hour (00-23)
                                 %I      hour (01-12)
                                 %j      day (001-366)
                                 %m      month (01-12)
                                 %M      minute (00-59)
                                 %p      am or pm
                                 %S      second (00-61)
                                 %u      day (1-7, Monday is first day of week)
                                 %U      week (00-53, first Sunday is first day of week one)
                                 %V      week (01-53, ISO 8601 style)
                                 %w      day (0-6)
                                 %W      week (00-53, first Monday is first day of week one)
                                 %x      date-time as in: Wed Oct  6 1993
                                 %X      time as in: 23:59:59
                                 %y      year (00-99)
                                 %Y      year as in: 1993
                                 %Z      timezone (or nothing if not determinable)
                                 %%      a bare percent sign

                    Other % specifications are undefined.  Other
                    characters will be passed through untouched.  Only
                    the C locale is supported.

                    The ----sssseeeeccccoooonnnnddddssss flag introduces a number of seconds
                    since the epoch to be used as a source from which



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                    to format.  Otherwise, the current time is used.

                    The ----ggggmmmmtttt flag forces timestamp output to use the
                    GMT timezone.  With no flag, the local timezone is
                    used.


          ttttrrrraaaapppp [[_c_o_m_m_a_n_d] _s_i_g_n_a_l_s]
                    causes the given _c_o_m_m_a_n_d to be executed upon
                    future receipt of any of the given signals.  The
                    command is executed in the global scope.  If
                    _c_o_m_m_a_n_d is absent, the signal action is returned.
                    If _c_o_m_m_a_n_d is the string SIG_IGN, the signals are
                    ignored.  If _c_o_m_m_a_n_d is the string SIG_DFL, the
                    signals are result to the system default.  _s_i_g_n_a_l_s
                    is either a single signal or a list of signals.
                    Signals may be specified numerically or
                    symbolically as per signal(3).  The "SIG" prefix
                    may be omitted.

                    With no arguments (or the argument -number), ttttrrrraaaapppp
                    returns the signal number of the trap command
                    currently being executed.

                    The ----ccccooooddddeeee flag uses the return code of the command
                    in place of whatever code Tcl was about to return
                    when the command originally started running.

                    The ----iiiinnnntttteeeerrrrpppp flag causes the command to be
                    evaluated using the interpreter active at the time
                    the command started running rather than when the
                    trap was declared.

                    The ----nnnnaaaammmmeeee flag causes the ttttrrrraaaapppp command to return
                    the signal name of the trap command currently
                    being executed.

                    The ----mmmmaaaaxxxx flag causes the ttttrrrraaaapppp command to return
                    the largest signal number that can be set.

                    For example, the command "trap {send_user "Ouch!"}
                    SIGINT" will print "Ouch!" each time the user
                    presses ^C.

                    By default, SIGINT (which can usually be generated
                    by pressing ^C) and SIGTERM cause Expect to exit.
                    This is due to the following trap, created by
                    default when Expect starts.

                                 trap exit {SIGINT SIGTERM}

                    If you use the -D flag to start the debugger,



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                    SIGINT is redefined to start the interactive
                    debugger.  This is due to the following trap:

                                 trap {exp_debug 1} SIGINT

                    The debugger trap can be changed by setting the
                    environment variable EXPECT_DEBUG_INIT to a new
                    trap command.

                    You can, of course, override both of these just by
                    adding trap commands to your script.  In
                    particular, if you have your own "trap exit
                    SIGINT", this will override the debugger trap.
                    This is useful if you want to prevent users from
                    getting to the debugger at all.

                    If you want to define your own trap on SIGINT but
                    still trap to the debugger when it is running,
                    use:

                                 if ![exp_debug] {trap mystuff SIGINT}

                    Alternatively, you can trap to the debugger using
                    some other signal.

                    ttttrrrraaaapppp will not let you override the action for
                    SIGALRM as this is used internally to EEEExxxxppppeeeecccctttt.  The
                    disconnect command sets SIGALRM to SIG_IGN
                    (ignore).  You can reenable this as long as you
                    disable it during subsequent spawn commands.

                    See signal(3) for more info.

          wwwwaaaaiiiitttt [_a_r_g_s]
                    delays until a spawned process (or the current
                    process if none is named) terminates.

                    wwwwaaaaiiiitttt normally returns a list of four integers.
                    The first integer is the pid of the process that
                    was waited upon.  The second integer is the
                    corresponding spawn id.  The third integer is -1
                    if an operating system error occurred, or 0
                    otherwise.  If the third integer was 0, the fourth
                    integer is the status returned by the spawned
                    process.  If the third integer was -1, the fourth
                    integer is the value of errno set by the operating
                    system.  The global variable errorCode is also
                    set.

                    Additional elements may appear at the end of the
                    return value from wwwwaaaaiiiitttt.  An optional fifth element
                    identifies a class of information.  Currently, the



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                    only possible value for this element is
                    CHILDKILLED in which case the next two values are
                    the C-style signal name and a short textual
                    description.

                    The ----iiii flag declares the process to wait
                    corresponding to the named spawn_id (NOT the
                    process id).  It is possible to wait for any
                    spawned process by using the spawn id -1.

                    The ----nnnnoooowwwwaaaaiiiitttt flag causes the wait to return
                    immediately with the indication of a successful
                    wait.  When the process exits (later), it will
                    automatically disappear without the need for an
                    explicit wait.

     LLLLIIIIBBBBRRRRAAAARRRRIIIIEEEESSSS
          Expect automatically knows about two built-in libraries for
          Expect scripts.  These are defined by the directories named
          in the variables exp_library and exp_exec_library.  Both are
          meant to contain utility files that can be used by other
          scripts.

          exp_library contains architecture-independent files.
          exp_exec_library contains architecture-dependent files.
          Depending on your system, both directories may be totally
          empty.  The existence of the file $exp_exec_library/cat-
          buffers describes whether your /bin/cat buffers by default.


     PPPPRRRREEEETTTTTTTTYYYY----PPPPRRRRIIIINNNNTTTTIIIINNNNGGGG
          A vgrind definition is available for pretty-printing EEEExxxxppppeeeecccctttt
          scripts.  Assuming the vgrind definition supplied with the
          EEEExxxxppppeeeecccctttt distribution is correctly installed, you can use it
          as:

                       vgrind -lexpect file


     EEEEXXXXAAAAMMMMPPPPLLLLEEEESSSS
          It many not be apparent how to put everything together that
          the man page describes.  I encourage you to read and try out
          the examples in the example directory of the EEEExxxxppppeeeecccctttt
          distribution.  Some of them are real programs.  Others are
          simply illustrative of certain techniques, and of course, a
          couple are just quick hacks.  The INSTALL file has a quick
          overview of these programs.

          The EEEExxxxppppeeeecccctttt papers (see SEE ALSO) are also useful.  While
          some papers use syntax corresponding to earlier versions of
          Expect, the accompanying rationales are still valid and go
          into a lot more detail than this man page.



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     CCCCAAAAVVVVEEEEAAAATTTTSSSS
          Extensions may collide with Expect's command names.  For
          example, sssseeeennnndddd is defined by Tk for an entirely different
          purpose.  For this reason, most of the EEEExxxxppppeeeecccctttt commands are
          also available as "exp_XXXX".  Commands and variables
          beginning with "exp", "inter", "spawn", and "timeout" do not
          have aliases.  Use the extended command names if you need
          this compatibility between environments.

          EEEExxxxppppeeeecccctttt takes a rather liberal view of scoping.  In
          particular, variables read by commands specific to the
          EEEExxxxppppeeeecccctttt program will be sought first from the local scope,
          and if not found, in the global scope.  For example, this
          obviates the need to place "global timeout" in every
          procedure you write that uses eeeexxxxppppeeeecccctttt.  On the other hand,
          variables written are always in the local scope (unless a
          "global" command has been issued).  The most common problem
          this causes is when spawn is executed in a procedure.
          Outside the procedure, _s_p_a_w_n__i_d no longer exists, so the
          spawned process is no longer accessible simply because of
          scoping.  Add a "global spawn_id" to such a procedure.

          If you cannot enable the multispawning capability (i.e.,
          your system supports neither select (BSD *.*), poll (SVR>2),
          nor something equivalent), EEEExxxxppppeeeecccctttt will only be able to
          control a single process at a time.  In this case, do not
          attempt to set _s_p_a_w_n__i_d, nor should you execute processes
          via exec while a spawned process is running.  Furthermore,
          you will not be able to eeeexxxxppppeeeecccctttt from multiple processes
          (including the user as one) at the same time.

          Terminal parameters can have a big effect on scripts.  For
          example, if a script is written to look for echoing, it will
          misbehave if echoing is turned off.  For this reason, Expect
          forces sane terminal parameters by default.  Unfortunately,
          this can make things unpleasant for other programs.  As an
          example, the emacs shell wants to change the "usual"
          mappings: newlines get mapped to newlines instead of
          carriage-return newlines, and echoing is disabled.  This
          allows one to use emacs to edit the input line.
          Unfortunately, Expect cannot possibly guess this.

          You can request that Expect not override its default setting
          of terminal parameters, but you must then be very careful
          when writing scripts for such environments.  In the case of
          emacs, avoid depending upon things like echoing and end-of-
          line mappings.

          The commands that accepted arguments braced into a single
          list (the eeeexxxxppppeeeecccctttt variants and iiiinnnntttteeeerrrraaaacccctttt) use a heuristic to
          decide if the list is actually one argument or many.  The
          heuristic can fail only in the case when the list actually



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          does represent a single argument which has multiple embedded
          \n's with non-whitespace characters between them.  This
          seems sufficiently improbable, however the argument "-brace"
          can be used to force a single argument to be handled as a
          single argument.  This could conceivably be used with
          machine-generated Expect code.

     BBBBUUUUGGGGSSSS
          It was really tempting to name the program "sex" (for either
          "Smart EXec" or "Send-EXpect"), but good sense (or perhaps
          just Puritanism) prevailed.

          On some systems, when a shell is spawned, it complains about
          not being able to access the tty but runs anyway.  This
          means your system has a mechanism for gaining the
          controlling tty that EEEExxxxppppeeeecccctttt doesn't know about.  Please find
          out what it is, and send this information back to me.

          Ultrix 4.1 (at least the latest versions around here)
          considers timeouts of above 1000000 to be equivalent to 0.

          Telnet (verified only under SunOS 4.1.2) hangs if TERM is
          not set.  This is a problem under cron and at, which do not
          define TERM.  Thus, you must set it explicitly - to what
          type is usually irrelevant.  It just has to be set to
          something!  The following probably suffices for most cases.

                       set env(TERM) vt100

          Some implementations of ptys are designed so that the kernel
          throws away any unread output after 10 to 15 seconds (actual
          number is implementation-dependent) after the process has
          closed the file descriptor.  Thus EEEExxxxppppeeeecccctttt programs such as

                       spawn date
                       sleep 20
                       expect

          will fail.  To avoid this, invoke non-interactive programs
          with eeeexxxxeeeecccc rather than ssssppppaaaawwwwnnnn.  While such situations are
          conceivable, in practice I have never encountered a
          situation in which the final output of a truly interactive
          program would be lost due to this behavior.

          On the other hand, Cray UNICOS ptys throw away any unread
          output immediately after the process has closed the file
          descriptor.  I have reported this to Cray and they are
          working on a fix.

          Sometimes a delay is required between a prompt and a
          response, such as when a tty interface is changing UART
          settings or matching baud rates by looking for start/stop



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          bits.  Usually, all this is require is to sleep for a second
          or two.  A more robust technique is to retry until the
          hardware is ready to receive input.  The following example
          uses both strategies:

                       send "speed 9600\r";
                       sleep 1
                       expect {
                               timeout {send "\r"; exp_continue}
                               $prompt
                       }



     EEEEXXXXPPPPEEEECCCCTTTT HHHHIIIINNNNTTTTSSSS
          There are a couple of things about EEEExxxxppppeeeecccctttt that may be non-
          intuitive.  This section attempts to address some of these
          things with a couple of suggestions.

          A common expect problem is how to recognize shell prompts.
          Since these are customized differently by differently people
          and different shells, portably automating rlogin can be
          difficult without knowing the prompt.  A reasonable
          convention is to have users store a regular expression
          describing their prompt (in particular, the end of it) in
          the environment variable EXPECT_PROMPT.  Code like the
          following can be used.  If EXPECT_PROMPT doesn't exist, the
          code still has a good chance of functioning correctly.

          set prompt "(%|#|\\$) $"          ;# default prompt
          catch {set prompt $env(EXPECT_PROMPT)}

          expect -re $prompt

          I encourage you to write eeeexxxxppppeeeecccctttt patterns that include the
          end of whatever you expect to see.  This avoids the
          possibility of answering a question before seeing the entire
          thing.  In addition, while you may well be able to answer
          questions before seeing them entirely, if you answer early,
          your answer may appear echoed back in the middle of the
          question.  In other words, the resulting dialogue will be
          correct but look scrambled.

          Most prompts include a space character at the end.  For
          example, the prompt from ftp is 'f', 't', 'p', '>' and
          <blank>.  To match this prompt, you must account for each of
          these characters.  It is a common mistake not to include the
          blank.  Put the blank in explicitly.

          If you use a pattern of the form X*, the * will match all
          the output received from the end of X to the last thing
          received.  This sounds intuitive but can be somewhat



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          confusing because the phrase "last thing received" can vary
          depending upon the speed of the computer and the processing
          of I/O both by the kernel and the device driver.

          In particular, humans tend to see program output arriving in
          huge chunks (atomically) when in reality most programs
          produce output one line at a time.  Assuming this is the
          case, the * in the pattern of the previous paragraph may
          only match the end of the current line even though there
          seems to be more, because at the time of the match that was
          all the output that had been received.

          eeeexxxxppppeeeecccctttt has no way of knowing that further output is coming
          unless your pattern specifically accounts for it.

          Even depending on line-oriented buffering is unwise.  Not
          only do programs rarely make promises about the type of
          buffering they do, but system indigestion can break output
          lines up so that lines break at seemingly random places.
          Thus, if you can express the last few characters of a prompt
          when writing patterns, it is wise to do so.

          If you are waiting for a pattern in the last output of a
          program and the program emits something else instead, you
          will not be able to detect that with the ttttiiiimmmmeeeeoooouuuutttt keyword.
          The reason is that eeeexxxxppppeeeecccctttt will not timeout - instead it will
          get an eeeeooooffff indication.  Use that instead.  Even better, use
          both.  That way if that line is ever moved around, you won't
          have to edit the line itself.

          Newlines are usually converted to carriage return, linefeed
          sequences when output by the terminal driver.  Thus, if you
          want a pattern that explicitly matches the two lines, from,
          say, printf("foo\nbar"), you should use the pattern
          "foo\r\nbar".

          A similar translation occurs when reading from the user, via
          eeeexxxxppppeeeecccctttt____uuuusssseeeerrrr.  In this case, when you press return, it will
          be translated to a newline.  If EEEExxxxppppeeeecccctttt then passes that to a
          program which sets its terminal to raw mode (like telnet),
          there is going to be a problem, as the program expects a
          true return.  (Some programs are actually forgiving in that
          they will automatically translate newlines to returns, but
          most don't.)  Unfortunately, there is no way to find out
          that a program put its terminal into raw mode.

          Rather than manually replacing newlines with returns, the
          solution is to use the command "stty raw", which will stop
          the translation.  Note, however, that this means that you
          will no longer get the cooked line-editing features.

          iiiinnnntttteeeerrrraaaacccctttt implicitly sets your terminal to raw mode so this



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          problem will not arise then.

          It is often useful to store passwords (or other private
          information) in EEEExxxxppppeeeecccctttt scripts.  This is not recommended
          since anything that is stored on a computer is susceptible
          to being accessed by anyone.  Thus, interactively prompting
          for passwords from a script is a smarter idea than embedding
          them literally.  Nonetheless, sometimes such embedding is
          the only possibility.

          Unfortunately, the UNIX file system has no direct way of
          creating scripts which are executable but unreadable.
          Systems which support setgid shell scripts may indirectly
          simulate this as follows:

          Create the EEEExxxxppppeeeecccctttt script (that contains the secret data) as
          usual.  Make its permissions be 750 (-rwxr-x---) and owned
          by a trusted group, i.e., a group which is allowed to read
          it.  If necessary, create a new group for this purpose.
          Next, create a /bin/sh script with permissions 2751
          (-rwxr-s--x) owned by the same group as before.

          The result is a script which may be executed (and read) by
          anyone.  When invoked, it runs the EEEExxxxppppeeeecccctttt script.

     SSSSEEEEEEEE AAAALLLLSSSSOOOO
          TTTTccccllll(3), lllliiiibbbbeeeexxxxppppeeeecccctttt(3)
          "_E_x_p_l_o_r_i_n_g _E_x_p_e_c_t: _A _T_c_l-_B_a_s_e_d _T_o_o_l_k_i_t _f_o_r _A_u_t_o_m_a_t_i_n_g
          _I_n_t_e_r_a_c_t_i_v_e _P_r_o_g_r_a_m_s" by Don Libes, pp. 602, ISBN 1-56592-
          090-2, O'Reilly and Associates, 1995.
          "_e_x_p_e_c_t: _C_u_r_i_n_g _T_h_o_s_e _U_n_c_o_n_t_r_o_l_l_a_b_l_e _F_i_t_s _o_f _I_n_t_e_r_a_c_t_i_v_i_t_y"
          by Don Libes, Proceedings of the Summer 1990 USENIX
          Conference, Anaheim, California, June 11-15, 1990.
          "_U_s_i_n_g eeeexxxxppppeeeecccctttt to Automate System Administration Tasks" by
          Don Libes, Proceedings of the 1990 USENIX Large Installation
          Systems Administration Conference, Colorado Springs,
          Colorado, October 17-19, 1990.
          "_T_c_l: _A_n _E_m_b_e_d_d_a_b_l_e _C_o_m_m_a_n_d _L_a_n_g_u_a_g_e" by John Ousterhout,
          Proceedings of the Winter 1990 USENIX Conference,
          Washington, D.C., January 22-26, 1990.
          "_e_x_p_e_c_t: _S_c_r_i_p_t_s _f_o_r _C_o_n_t_r_o_l_l_i_n_g _I_n_t_e_r_a_c_t_i_v_e _P_r_o_g_r_a_m_s" by
          Don Libes, Computing Systems, Vol. 4, No. 2, University of
          California Press Journals, November 1991.
          "_R_e_g_r_e_s_s_i_o_n _T_e_s_t_i_n_g _a_n_d _C_o_n_f_o_r_m_a_n_c_e _T_e_s_t_i_n_g _I_n_t_e_r_a_c_t_i_v_e
          _P_r_o_g_r_a_m_s", by Don Libes, Proceedings of the Summer 1992
          USENIX Conference, pp. 135-144, San Antonio, TX, June 12-15,
          1992.
          "_K_i_b_i_t_z - _C_o_n_n_e_c_t_i_n_g _M_u_l_t_i_p_l_e _I_n_t_e_r_a_c_t_i_v_e _P_r_o_g_r_a_m_s
          _T_o_g_e_t_h_e_r", by Don Libes, Software - Practice & Experience,
          John Wiley & Sons, West Sussex, England, Vol. 23, No. 5,
          May, 1993.
          "_A _D_e_b_u_g_g_e_r _f_o_r _T_c_l _A_p_p_l_i_c_a_t_i_o_n_s", by Don Libes, Proceedings



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     EEEEXXXXPPPPEEEECCCCTTTT((((1111))))       UUUUNNNNIIIIXXXX SSSSyyyysssstttteeeemmmm VVVV ((((22229999 DDDDeeeecccceeeemmmmbbbbeeeerrrr 1111999999994444))))        EEEEXXXXPPPPEEEECCCCTTTT((((1111))))



          of the 1993 Tcl/Tk Workshop, Berkeley, CA, June 10-11, 1993.

     AAAAUUUUTTTTHHHHOOOORRRR
          Don Libes, National Institute of Standards and Technology

     AAAACCCCKKKKNNNNOOOOWWWWLLLLEEEEDDDDGGGGEEEEMMMMEEEENNNNTTTTSSSS
          Thanks to John Ousterhout for Tcl, and Scott Paisley for
          inspiration.  Thanks to Rob Savoye for Expect's
          autoconfiguration code.

          The HISTORY file documents much of the evolution of eeeexxxxppppeeeecccctttt.
          It makes interesting reading and might give you further
          insight to this software.  Thanks to the people mentioned in
          it who sent me bug fixes and gave other assistance.

          Design and implementation of EEEExxxxppppeeeecccctttt was paid for in part by
          the U.S. government and is therefore in the public domain.
          However the author and NIST would like credit if this
          program and documentation or portions of them are used.




































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