Fresh Fish 8/FreshFishVol8-CD1.bin/gnu/info/sh-utils.info

GNU Info File | 1994-12-22 | 96KB | 2,065 lines

This is Info file sh-utils.info, produced by Makeinfo-1.55 from the
input file sh-utils.texi.
START-INFO-DIR-ENTRY
* Shell utilities: (sh-utils).        GNU shell utilities.
* basename: (sh-utils)basename invocation.    Strip directory and suffix.
* date: (sh-utils)date invocation.        Print/set system date and time.
* dirname: (sh-utils)dirname invocation.    Strip non-directory suffix.
* echo: (sh-utils)echo invocation.        Print a line of text.
* env: (sh-utils)env invocation.        Modify the environment.
* expr: (sh-utils)expr invocation.        Evaluate expressions.
* false: (sh-utils)false invocation.        Do nothing, unsuccessfully.
* groups: (sh-utils)groups invocation.        Print group names a user is in.
* hostname: (sh-utils)hostname invocation.    Print or set system name.
* id: (sh-utils)id invocation.            Print real/effective uid/gid.
* logname: (sh-utils)logname invocation.    Print current login name.
* nice: (sh-utils)nice invocation.        Modify scheduling priority.
* pathchk: (sh-utils)pathchk invocation.    Check file name portability.
* printenv: (sh-utils)printenv invocation.    Print environment variables.
* printf: (sh-utils)printf invocation.            Format and print data.
* pwd: (sh-utils)pwd invocation.            Print working directory.
* sleep: (sh-utils)sleep invocation.            Delay for a specified time.
* stty: (sh-utils)stty invocation.            Print/change terminal settings.
* su: (sh-utils)su invocation.                    Modify user and group id.
* tee: (sh-utils)tee invocation.            Redirect to multiple files.
* test: (sh-utils)test invocation.            File/string tests.
* true: (sh-utils)true invocation.            Do nothing, successfully.
* tty: (sh-utils)tty invocation.            Print terminal name.
* uname: (sh-utils)uname invocation.            Print system information.
* users: (sh-utils)users invocation.            Print current user names.
* who: (sh-utils)who invocation.            Print who is logged in.
* whoami: (sh-utils)whoami invocation.        Print effective user id.
* yes: (sh-utils)yes invocation.        Print a string indefinitely.
END-INFO-DIR-ENTRY
   This file documents the GNU shell utilities.
   Copyright (C) 1994 Free Software Foundation, Inc.
   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Foundation.
File: sh-utils.info,  Node: Top,  Next: Introduction,  Prev: (DIR),  Up: (DIR)
GNU shell utilities
*******************
   This manual minimally documents version GNU sh-utils 1.12 of the GNU
shell utilities.
* Menu:
* Introduction::        Caveats, overview, and authors.
* Common options::              Common options.
* Printing text::               echo printf yes
* Conditions::                  false true test expr
* Redirection::                 tee
* File name manipulation::      dirname basename pathchk
* Working context information:: pwd stty printenv tty
* User information::            id logname whoami groups users who
* System context::              date uname hostname
* Modified command invocation:: env nice nohup su
* Delaying::                    sleep
* Index::                       General index.
File: sh-utils.info,  Node: Introduction,  Next: Common options,  Prev: Top,  Up: Top
Introduction
************
   First of all, this manual is incomplete.  The `stty' section, in
particular, needs substantial reorganization and additional explanatory
text before it will be up to the standard of other GNU manuals.
Explanatory text in general is lacking; the manual presently assumes you
pretty much know what to do, and just need to be reminded of how.  Thus,
if you are interested, please get involved in improving this manual.
The entire GNU community will benefit.
   Some of these programs are useful only when writing shell scripts;
utilities like these are, in fact, the "language" of shell scripts (to
a great extent).  Others are occasionally useful interactively.
   The GNU shell utilities are mostly compatible with the POSIX.2
standard.
   Please report bugs to `[e-mail]'.  Remember to
include the version number, machine architecture, input files, and any
other information needed to reproduce the bug.  *Note Bugs: (gcc)Bugs.
   This manual is based on the Unix man pages in the distribution, which
were originally written by David MacKenzie and updated by Jim Meyering.
Franc,ois Pinard did the initial conversion to Texinfo format.  Karl
Berry did the indexing, some reorganization, and editing of the results.
Richard Stallman contributed his usual invaluable insights to the
overall process.
File: sh-utils.info,  Node: Common options,  Next: Printing text,  Prev: Introduction,  Up: Top
Common options
**************
   Certain options are available in all these programs.  Rather than
writing identical descriptions for each of the programs, they are
described here.  (In fact, every GNU program accepts (or should accept)
these options.)
   Many of these programs take arbitrary strings as arguments.  In those
cases, `--help' and `--version' are taken as these options only if
there is one and exactly one command line argument.
`--help'
     Print a usage message listing all available options, then exit
     successfully.
`--version'
     Print the version number, then exit successfully.
File: sh-utils.info,  Node: Printing text,  Next: Conditions,  Prev: Common options,  Up: Top
Printing text
*************
   This section describes commands that display text strings.
* Menu:
* echo invocation::             Print a line of text.
* printf invocation::           Format and print data.
* yes invocation::              Print a string until interrupted.
File: sh-utils.info,  Node: echo invocation,  Next: printf invocation,  Up: Printing text
`echo': Print a line of text
============================
   Synopsis:
     echo [ OPTION ]... [ STRING ]...
   `echo' writes each given STRING to standard output, with a space
between each and a newline after the last one.
   The program accepts the following options.  Also see *Note Common
options::.
     Do not output the trailing newline.
     Enable interpretation of the following backslash-escaped
     characters in each STRING:
    `\a'
          alert (bell)
    `\b'
          backspace
    `\c'
          suppress trailing newline
    `\f'
          form feed
    `\n'
          new line
    `\r'
          carriage return
    `\t'
          horizontal tab
    `\v'
          vertical tab
    `\\'
          backslash
    `\NNN'
          the character whose ASCII code is NNN (octal); if NNN is not
          a valid octal number, it is printed literally.
File: sh-utils.info,  Node: printf invocation,  Next: yes invocation,  Prev: echo invocation,  Up: Printing text
`printf': Format and print data
===============================
   Synopsis:
     printf FORMAT [ ARGUMENT ]...
   `printf' prints the FORMAT string, interpreting `%' directives and
`\' escapes in the same way as the C `printf' function.  The FORMAT
argument is re-used as necessary to convert all of the given ARGUMENTs.
   `printf' has one additional directive, `%b', which prints its
argument string with `\' escapes interpreted in the same way as in the
FORMAT string.
   `printf' interprets `\0ooo' in FORMAT as an octal number (if OOO is
0 to 3 octal digits) specifying a character to print, and `\xhhh' as a
hexadecimal number (if HHH is 1 to 3 hex digits) specifying a character
to print.
   An additional escape, `\c', causes `printf' to produce no further
output.
   The only options are a lone `--help' or `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: yes invocation,  Prev: printf invocation,  Up: Printing text
`yes': Print a string until interrupted
=======================================
   `yes' prints the command line arguments, separated by spaces and
followed by a newline, forever until it is killed.  If no arguments are
given, it prints `y' followed by a newline forever until killed.
   The only options are a lone `--help' or `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: Conditions,  Next: Redirection,  Prev: Printing text,  Up: Top
Conditions
**********
   This section describes commands that are primarily useful for their
exit status, rather than their output.  Thus, they are often used as the
condition of shell `if' statements, or as the last command in a
pipeline.
* Menu:
* false invocation::            Do nothing, unsuccessfully.
* true invocation::             Do nothing, successfully.
* test invocation::             Check file types and compare values.
* expr invocation::             Evaluate expressions.
File: sh-utils.info,  Node: false invocation,  Next: true invocation,  Up: Conditions
`false': Do nothing, unsuccessfully
===================================
   `false' does nothing except return an exit status of 1, meaning
"failure".  It can be used as a place holder in shell scripts where an
unsuccessful command is needed.
   Any arguments are ignored, except for a lone `--help' or `--version'
(*note Common options::.).
File: sh-utils.info,  Node: true invocation,  Next: test invocation,  Prev: false invocation,  Up: Conditions
`true': Do nothing, successfully
================================
   `true' does nothing except return an exit status of 0, meaning
"success".  It can be used as a place holder in shell scripts where a
successful command is needed, although the shell built-in command `:'
(colon) may be faster.
   Any arguments are ignored, except for a lone `--help' or `--version'
(*note Common options::.).
File: sh-utils.info,  Node: test invocation,  Next: expr invocation,  Prev: true invocation,  Up: Conditions
`test': Check file types and compare values
===========================================
   `test' returns a status of 0 (true) or 1 (false) depending on the
evaluation of the conditional expression EXPR.  Each part of the
expression must be a separate argument.
   `test' has file status checks, string operators, and numeric
comparison operators.
   Because most shells have a built-in command by the same name, using
the unadorned command name in a script or interactively may get you
different functionality than that described here.
   Besides the options below, `test' accepts a lone `--help' or
`--version'.  *Note Common options::.  A single non-option argument is
also allowed: `test' returns true if the argument is not null.
* Menu:
* File type tests::             -[bcdfhLpSt]
* Access permission tests::     -[gkruwxOG]
* File characteristics tests::  -e -s -nt -ot -ef
* String tests::                -z -n = !=
* Numeric tests::               -eq -ne -lt -le -gt -ge
* Connectives for test::        ! -a -o
File: sh-utils.info,  Node: File type tests,  Next: Access permission tests,  Up: test invocation
File type tests
---------------
   These options test for particular types of files.  (Everything's a
file, but not all files are the same!)
`-b FILE'
     True if FILE exists and is a block special device.
`-c FILE'
     True if FILE exists and is a character special device.
`-d FILE'
     True if FILE exists and is a directory.
`-f FILE'
     True if FILE exists and is a regular file.
`-h FILE'
`-L FILE'
     True if FILE exists and is a symbolic link.
`-p FILE'
     True if FILE exists and is a named pipe.
`-S FILE'
     True if FILE exists and is a socket.
`-t [ FD ]'
     True if FD is opened on a terminal.  If FD is omitted, it defaults
     to 1 (standard output).
File: sh-utils.info,  Node: Access permission tests,  Next: File characteristics tests,  Prev: File type tests,  Up: test invocation
Access permission tests
-----------------------
   These options test for particular access permissions.
`-g FILE'
     True if FILE exists and has its set-group-id bit set.
`-k FILE'
     True if FILE has its "sticky" bit set.
`-r FILE'
     True if FILE exists and is readable.
`-u FILE'
     True if FILE exists and has its set-user-id bit set.
`-w FILE'
     True if FILE exists and is writable.
`-x FILE'
     True if FILE exists and is executable.
`-O FILE'
     True if FILE exists and is owned by the current effective user id.
`-G FILE'
     True if FILE exists and is owned by the current effective group id.
File: sh-utils.info,  Node: File characteristics tests,  Next: String tests,  Prev: Access permission tests,  Up: test invocation
File characteristics tests
--------------------------
   These options test other file characteristics.
`-e FILE'
     True if FILE exists.
`-s FILE'
     True if FILE exists and has a size greater than zero.
`FILE1 -nt FILE2'
     True if FILE1 is newer (according to modification date) than FILE2.
`FILE1 -ot FILE2'
     True if FILE1 is older (according to modification date) than FILE2.
`FILE1 -ef FILE2'
     True if FILE1 and FILE2 have the same device and inode numbers,
     i.e., if they are hard links to each other.
File: sh-utils.info,  Node: String tests,  Next: Numeric tests,  Prev: File characteristics tests,  Up: test invocation
String tests
------------
   These options test string characteristics.  Strings are not quoted
for `test', though you may need to quote them to protect characters
with special meaning to the shell, e.g., spaces.
`-z STRING'
     True if the length of STRING is zero.
`-n STRING'
`STRING'
     True if the length of STRING is non-zero.
`STRING1 = STRING2'
     True if the strings are equal.
`STRING1 != STRING2'
     True if the strings are not equal.
File: sh-utils.info,  Node: Numeric tests,  Next: Connectives for test,  Prev: String tests,  Up: test invocation
Numeric tests
-------------
   Numeric relationals.  The arguments must be entirely numeric
(possibly negative), or the special expression `-l STRING', which
evaluates to the length of STRING.
`ARG1 -eq ARG2'
`ARG1 -ne ARG2'
`ARG1 -lt ARG2'
`ARG1 -le ARG2'
`ARG1 -gt ARG2'
`ARG1 -ge ARG2'
     These arithmetic binary operators return true if ARG1 is equal,
     not-equal, less-than, less-than-or-equal, greater-than, or
     greater-than-or-equal than ARG2, respectively.
   For example:
     test -1 -gt -2 && echo yes
     => yes
     test -l abc -gt 1 && echo yes
     => yes
     test 0x100 -eq 1
     error--> test: integer expression expected before -eq
File: sh-utils.info,  Node: Connectives for test,  Prev: Numeric tests,  Up: test invocation
Connectives for `test'
----------------------
   The usual logical connectives.
`! EXPR'
     True if EXPR is false.
`EXPR1 -a EXPR2'
     True if both EXPR1 and EXPR2 are true.
`EXPR1 -o EXPR2'
     True if either EXPR1 or EXPR2 is true.
File: sh-utils.info,  Node: expr invocation,  Prev: test invocation,  Up: Conditions
`expr': Evaluate expressions
============================
   `expr' evaluates an expression and writes the result on standard
output.  Each token of the expression must be a separate argument.
   Operands are either numbers or strings.  `expr' coerces anything
appearing in an operand position to an integer or a string depending on
the operation being applied to it.
   Strings are not quoted for `expr', though you may need to quote them
to protect characters with special meaning to the shell, e.g., spaces.
   Operators may given as infix symbols or prefix keywords.  Parentheses
may be used for grouping in the usual manner (you must quote parentheses
to avoid the shell evaluating them, however).
   Exit status:
     0 if the expression is neither null nor 0,
     1 if the expression is null or 0,
     2 for invalid expressions.
* Menu:
* Relations for expr::          | & < <= = == != >= >
* Numeric expressions::         + - * / %
* String expressions::          : match substr index length
* Examples of expr::            Examples.
File: sh-utils.info,  Node: Relations for expr,  Next: Numeric expressions,  Up: expr invocation
Relations for `expr'
--------------------
   The usual logical connectives and relations, in order of precedence.
     Yields its first argument if it is neither null nor 0, otherwise
     its second argument.
     Yields its first argument if neither argument is null or 0,
     otherwise 0.
`< <= = == != >= >'
     Compare the arguments and return 1 if the relation is true, 0
     otherwise.  `==' is a synonym for `='.  `expr' first tries to
     coerce both arguments to numbers and do a numeric comparison; if
     either coercion fails, it does a lexicographic comparison.
File: sh-utils.info,  Node: Numeric expressions,  Next: String expressions,  Prev: Relations for expr,  Up: expr invocation
Numeric expressions
-------------------
   Numeric operators, in order of increasing precedence.  The
connectives (previous section) have higher precedence, the string
operators (following section) have lower.
`+ -'
     Addition and subtraction.  Both arguments are coerced to numbers;
     an error occurs if this cannot be done.
`* / %'
     Multiplication, division, remainder.  Both arguments are coerced to
     numbers; an error occurs if this cannot be done.
File: sh-utils.info,  Node: String expressions,  Next: Examples of expr,  Prev: Numeric expressions,  Up: expr invocation
String expressions
------------------
   String operators.  These have lowest precedence.
`STRING : REGEX'
     Perform pattern matching.  The arguments are coerced to strings
     and the second is considered to be a (basic, a la `grep') regular
     expression, with a `^' implicitly prepended.  The first argument is
     then matched against this regular expression.
     If the match succeeds and REGEX uses `\(' and `\)', the `:'
     expression returns the part of STRING that matched the
     subexpression; otherwise, it returns the number of characters
     matched.
     If the match fails, the `:' operator returns the null string if
     `\(' and `\)' are used in REGEX, otherwise 0.
     Only the first `\( ... \)' pair is relevant to the return value;
     additional pairs are meaningful only for grouping the regular
     expression operators.
     *Note Regular Expression Library: (regex)Top, for details of
     regular expression syntax.
`match STRING REGEX'
     An alternative way to do pattern matching.  This is the same as
     `STRING : REGEX'.
`substr STRING POSITION LENGTH'
     Returns the substring of STRING beginning at POSITION with length
     at most LENGTH.  If either POSITION or LENGTH is negative or
     non-numeric, returns the null string.
`index STRING CHARACTER-CLASS'
     Returns the first position in STRING where the first character in
     CHARSET was found.  If no character in CHARSET is found in STRING,
     return 0.
`length STRING'
     Returns the length of STRING.
   The keywords cannot be used as strings.
File: sh-utils.info,  Node: Examples of expr,  Prev: String expressions,  Up: expr invocation
Examples of `expr'
------------------
   Here are a few examples, including quoting for shell metacharacters.
   To add 1 to the shell variable `foo', in Bourne-compatible shells:
     foo=`expr $foo + 1`
   To print the non-directory part of the file name stored in `$fname',
which need not contain a `/'.
     expr $fname : '.*/\(^.*\)' '^|' $fname
     expr abc : 'a\(.\)c'
     => b
     expr index abcdef cz
     => 3
     expr index index a
     error--> expr: syntax error
File: sh-utils.info,  Node: Redirection,  Next: File name manipulation,  Prev: Conditions,  Up: Top
Redirection
***********
   Unix shells commonly provide several forms of "redirection"--ways to
change the input source or output destination of a command.  But one
useful redirection is performed by a separate command, not by the shell;
it's described here.
* Menu:
* tee invocation::              Redirect output to multiple files.
File: sh-utils.info,  Node: tee invocation,  Up: Redirection
`tee': Redirect output to multiple files
========================================
   The `tee' command copies standard input to standard output and also
to any files given as arguments.  This is useful when you want not only
to send some data down a pipe, but also to save a copy.
   Synopsis:
     tee [ OPTION ]... [ FILE ]...
   If a file being written to does not already exist, it is created.
If a file being written to already exists, the data it previously
contained is overwritten unless the `-a' option is used.
   The program accepts the following options.  Also see *Note Common
options::.
`--append'
     Append standard input to the given files rather than overwriting
     them.
`--ignore-interrupts'
     Ignore interrupt signals.
File: sh-utils.info,  Node: File name manipulation,  Next: Working context information,  Prev: Redirection,  Up: Top
File name manipulation
**********************
   This section describes commands that manipulate file names.
* Menu:
* basename invocation::         Strip directory and suffix from a file name.
* dirname invocation::          Strip non-directory suffix from a file name.
* pathchk invocation::          Check file name portability.
File: sh-utils.info,  Node: basename invocation,  Next: dirname invocation,  Up: File name manipulation
`basename': Strip directory and suffix from a file name
=======================================================
   Synopsis:
     basename NAME [ SUFFIX ]
   The `basename' command removes any leading directory components from
NAME.  If SUFFIX is specified and is identical to the end of NAME, it
is removed from NAME as well.  `basename' prints the result on standard
output.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: dirname invocation,  Next: pathchk invocation,  Prev: basename invocation,  Up: File name manipulation
`dirname': Strip non-directory suffix from a file name
======================================================
   Synopsis:
     dirname NAME
   `dirname' prints all but the final slash-delimited component of
NAME.  If NAME is a single component, `dirname' prints `.' (meaning the
current directory).
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: pathchk invocation,  Prev: dirname invocation,  Up: File name manipulation
`pathchk': Check file name portability
======================================
   Synopsis:
     pathchk [ OPTION ]... NAME...
   For each NAME, `pathchk' prints a message if any of these conditions
is true:
  1. one of the existing directories in NAME does not have search
     (execute) permission,
  2. the length of NAME is larger than its filesystem's maximum file
     name length,
  3. the length of one component of NAME, corresponding to an existing
     directory name, is larger than its filesystem's maximum length for
     a file name component.
   The program accepts the following option.  Also see *Note Common
options::.
`--portability'
     Instead of performing length checks on the underlying filesystem,
     test the length of each file name and its components against the
     POSIX.1 minimum limits for portability.  Also check that the file
     name contains no characters not in the portable file name
     character set.
   Exit status:
     0 if all specified file names passed all of the tests,
     1 otherwise.
File: sh-utils.info,  Node: Working context information,  Next: User information,  Prev: File name manipulation,  Up: Top
Working context information
***************************
   This section describes commands that display or alter the context in
which you are working: the current directory, the terminal settings, and
so forth.  See also the user-related commands in the next section.
* Menu:
* pwd invocation::              Print working directory.
* stty invocation::             Print or change terminal characteristics.
* printenv invocation::         Print environment variables.
* tty invocation::              Print file name of terminal on standard input.
File: sh-utils.info,  Node: pwd invocation,  Next: stty invocation,  Up: Working context information
`pwd': Print working directory
==============================
   `pwd' prints the fully resolved name of the current directory.  That
is, all components of the printed name will be actual directory
names--none will be symbolic links.
   Because most shells have a built-in command by the same name, using
the unadorned command name in a script or interactively may get you
different functionality than that described here.
   The only options are a lone `--help' or `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: stty invocation,  Next: printenv invocation,  Prev: pwd invocation,  Up: Working context information
`stty': Print or change terminal characteristics
================================================
   If given no arguments, `stty' prints the baud rate, line discipline
number (on systems that support it), and line settings that have been
changed from the values set by `stty sane'.  Mode reading and setting
are performed on the tty line connected to standard input.
   `stty' accepts many non-option arguments that change aspects of the
terminal line operation, as described below.
   Synopses:
     stty [ SETTING ]...
     stty [ OPTION ]
   The program accepts the following options.  Also see *Note Common
options::.
`--all'
     Print all current settings in human-readable form.
`--save'
     Print all current settings in a form that can be used as an
     argument to another `stty' command to restore the current settings.
   Many settings can be turned off by preceding them with a `-'.  Such
arguments are marked below with "May be negated" in their description.
The descriptions themselves refer to the positive case, that is, when
*not* negated (unless stated otherwise, of course).
   Some settings are not available on all POSIX systems, since they use
extensions.  Such arguments are marked below with "Non-POSIX" in their
description.  On non-POSIX systems, those or other settings also may not
be available, but it's not feasible to document all the variations: just
try it and see.
* Menu:
* Control::                     Control settings
* Input::                       Input settings
* Output::                      Output settings
* Local::                       Local settings
* Combination::                 Combination settings
* Characters::                  Special characters
* Special::                     Special settings
File: sh-utils.info,  Node: Control,  Next: Input,  Up: stty invocation
Control settings
----------------
   Control settings:
`parenb'
     Generate parity bit in output and expect parity bit in input.  May
     be negated.
`parodd'
     Set odd parity (even if negated).  May be negated.
`cs5'
`cs6'
`cs7'
`cs8'
     Set character size to 5, 6, 7, or 8 bits.
`hup'
`hupcl'
     Send a hangup signal when the last process closes the tty.  May be
     negated.
`cstopb'
     Use two stop bits per character (one if negated).  May be negated.
`cread'
     Allow input to be received.  May be negated.
`clocal'
     Disable modem control signals.  May be negated.
`crtscts'
     Enable RTS/CTS flow control.  Non-POSIX.  May be negated.
File: sh-utils.info,  Node: Input,  Next: Output,  Prev: Control,  Up: stty invocation
Input settings
--------------
`ignbrk'
     Ignore breaks.  May be negated.
`brkint'
     Make breaks cause an interrupt signal.  May be negated.
`ignpar'
     Ignore parity errors.  May be negated.
`parmrk'
     Mark parity errors (with a 255-0-character sequence).  May be
     negated.
`inpck'
     Enable input parity checking.  May be negated.
`istrip'
     Clear high (8th) bit of input characters.  May be negated.
`inlcr'
     Translate newline to carriage return.  May be negated.
`igncr'
     Ignore carriage return.  May be negated.
`icrnl'
     Translate carriage return to newline.  May be negated.
`ixon'
     Enable XON/XOFF flow control (that is, CTRL-s/CTRL-Q).  May be
     negated.
`ixoff'
`tandem'
     Enable sending of `stop' character when the system input buffer is
     almost full, and `start' character when it becomes almost empty
     again.  May be negated.
`iuclc'
     Translate uppercase characters to lowercase.  Non-POSIX.  May be
     negated.
`ixany'
     Allow any character to restart output (only the start character if
     negated).  Non-POSIX.  May be negated.
`imaxbel'
     Enable beeping and not flushing input buffer if a character arrives
     when the input buffer is full.  Non-POSIX.  May be negated.
File: sh-utils.info,  Node: Output,  Next: Local,  Prev: Input,  Up: stty invocation
Output settings
---------------
   These arguments specify output-related operations.
`opost'
     Postprocess output.  May be negated.
`olcuc'
     Translate lowercase characters to uppercase.  Non-POSIX.  May be
     negated.
`ocrnl'
     Translate carriage return to newline.  Non-POSIX.  May be negated.
`onlcr'
     Translate newline to carriage return-newline.  Non-POSIX.  May be
     negated.
`onocr'
     Do not print carriage returns in the first column.  Non-POSIX.
     May be negated.
`onlret'
     Newline performs a carriage return.  Non-POSIX.  May be negated.
`ofill'
     Use fill (padding) characters instead of timing for delays.
     Non-POSIX.  May be negated.
`ofdel'
     Use delete characters for fill instead of null characters.
     Non-POSIX.  May be negated.
`nl1'
`nl0'
     Newline delay style.  Non-POSIX.
`cr3'
`cr2'
`cr1'
`cr0'
     Carriage return delay style.  Non-POSIX.
`tab3'
`tab2'
`tab1'
`tab0'
     Horizontal tab delay style.  Non-POSIX.
`bs1'
`bs0'
     Backspace delay style.  Non-POSIX.
`vt1'
`vt0'
     Vertical tab delay style.  Non-POSIX.
`ff1'
`ff0'
     Form feed delay style.  Non-POSIX.
File: sh-utils.info,  Node: Local,  Next: Combination,  Prev: Output,  Up: stty invocation
Local settings
--------------
`isig'
     Enable `interrupt', `quit', and `suspend' special characters.  May
     be negated.
`icanon'
     Enable `erase', `kill', `werase', and `rprnt' special characters.
     May be negated.
`iexten'
     Enable non-POSIX special characters.  May be negated.
`echo'
     Echo input characters.  May be negated.
`echoe'
`crterase'
     Echo `erase' characters as backspace-space-backspace.  May be
     negated.
`echok'
     Echo a newline after a `kill' character.  May be negated.
`echonl'
     Echo newline even if not echoing other characters.  May be negated.
`noflsh'
     Disable flushing after `interrupt' and `quit' special characters.
     May be negated.
`xcase'
     Enable input and output of uppercase characters by preceding their
     lowercase equivalents with `\', when `icanon' is set.  Non-POSIX.
     May be negated.
`tostop'
     Stop background jobs that try to write to the terminal.  Non-POSIX.
     May be negated.
`echoprt'
`prterase'
     Echo erased characters backward, between `\' and `/'.  Non-POSIX.
     May be negated.
`echoctl'
`ctlecho'
     Echo control characters in hat notation (`^C') instead of
     literally.  Non-POSIX.  May be negated.
`echoke'
`crtkill'
     Echo the `kill' special character by erasing each character on the
     line as indicated by the `echoprt' and `echoe' settings, instead
     of by the `echoctl' and `echok' settings.  Non-POSIX.  May be
     negated.
File: sh-utils.info,  Node: Combination,  Next: Characters,  Prev: Local,  Up: stty invocation
Combination settings
--------------------
   Combination settings:
`evenp'
`parity'
     Same as `parenb -parodd cs7'.  May be negated.  If negated, same
     as `-parenb cs8'.
`oddp'
     Same as `parenb parodd cs7'.  May be negated.  If negated, same as
     `-parenb cs8'.
     Same as `-icrnl -onlcr'.  May be negated.  If negated, same as
     `icrnl -inlcr -igncr onlcr -ocrnl -onlret'.
     Reset the `erase' and `kill' special characters to their default
     values.
`sane'
     Same as:
          cread -ignbrk brkint -inlcr -igncr icrnl -ixoff -iuclc -ixany
          imaxbel opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel
          nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl
          -noflsh -xcase -tostop -echoprt echoctl echoke
      and also sets all special characters to their default values.
`cooked'
     Same as `brkint ignpar istrip icrnl ixon opost isig icanon', plus
     sets the `eof' and `eol' characters to their default values if
     they are the same as the `min' and `time' characters.  May be
     negated.  If negated, same as `raw'.
`raw'
     Same as:
          -ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr
          -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -opost -isig -icanon
          -xcase min 1 time 0
      May be negated.  If negated, same as `cooked'.
`cbreak'
     Same as `-icanon'.  May be negated.  If negated, same as `icanon'.
`pass8'
     Same as `-parenb -istrip cs8'.  May be negated.  If negated, same
     as `parenb istrip cs7'.
`litout'
     Same as `-parenb -istrip -opost cs8'.  May be negated.  If
     negated, same as `parenb istrip opost cs7'.
`decctlq'
     Same as `-ixany'.  Non-POSIX.  May be negated.
`tabs'
     Same as `tab0'.  Non-POSIX.  May be negated.  If negated, same as
     `tab3'.
`lcase'
`LCASE'
     Same as `xcase iuclc olcuc'.  Non-POSIX.  May be negated.
`crt'
     Same as `echoe echoctl echoke'.
`dec'
     Same as `echoe echoctl echoke -ixany intr ^C erase ^? kill C-u'.
File: sh-utils.info,  Node: Characters,  Next: Special,  Prev: Combination,  Up: stty invocation
Special characters
------------------
   The special characters' default values vary from system to system.
They are set with the syntax `name value', where the names are listed
below and the value can be given either literally, in hat notation
(`^C'), or as an integer which may start with `0x' to indicate
hexadecimal, `0' to indicate octal, or any other digit to indicate
decimal.
   For GNU stty, giving a value of `^-' or `undef' disables that
special character.  (This is incompatible with Ultrix `stty', which
uses  a value of `u' to disable a special character.  GNU `stty' treats
a value `u' like any other, namely to set that special character to u.)
`intr'
     Send an interrupt signal.
`quit'
     Send a quit signal.
`erase'
     Erase the last character typed.
`kill'
     Erase the current line.
`eof'
     Send an end of file (terminate the input).
`eol'
     End the line.
`eol2'
     Alternate character to end the line.  Non-POSIX.
`swtch'
     Switch to a different shell layer.  Non-POSIX.
`start'
     Restart the output after stopping it.
`stop'
     Stop the output.
`susp'
     Send a terminal stop signal.
`dsusp'
     Send a terminal stop signal after flushing the input.  Non-POSIX.
`rprnt'
     Redraw the current line.  Non-POSIX.
`werase'
     Erase the last word typed.  Non-POSIX.
`lnext'
     Enter the next character typed literally, even if it is a special
     character.  Non-POSIX.
File: sh-utils.info,  Node: Special,  Prev: Characters,  Up: stty invocation
Special settings
----------------
`min N'
     Set the minimum number of characters that will satisfy a read until
     the time value has expired, when `-icanon' is set.
`time N'
     Set the number of tenths of a second before reads time out if the
     min number of characters have not been read, when `-icanon' is set.
`ispeed N'
     Set the input speed to N.
`ospeed N'
     Set the output speed to N.
`rows N'
     Tell the tty kernel driver that the terminal has N rows.
     Non-POSIX.
`cols N'
`columns N'
     Tell the kernel that the terminal has N columns.  Non-POSIX.
`size'
     Print the number of rows and columns that the kernel thinks the
     terminal has.  (Systems that don't support rows and cols in the
     kernel typically use the environment variables `LINES' and
     `COLUMNS' instead; however, GNU `stty' does not know anything
     about them.) Non-POSIX.
`line N'
     Use line discipline N.  Non-POSIX.
`speed'
     Print the terminal speed.
     Set the input and output speeds to N.  N can be one of: 0 50 75
     110 134 134.5 150 200 300 600 1200 1800 2400 4800 9600 19200 38400
     `exta' `extb'.  `exta' is the same as 19200; `extb' is the same as
     38400.  0 hangs up the line if `-clocal' is set.
File: sh-utils.info,  Node: printenv invocation,  Next: tty invocation,  Prev: stty invocation,  Up: Working context information
`printenv': Print all or some environment variables
===================================================
   Synopsis:
     printenv [ OPTION ] [ VARIABLE ]...
   If no VARIABLEs are specified, `printenv' prints the value of every
environment variable.  Otherwise, it prints the value of each VARIABLE
that is set, and nothing for those that are not set.
   The only options are a lone `--help' or `--version'.  *Note Common
options::.
   Exit status:
     0 if all variables specified were found
     1 if at least one specified variable was not found
     2 if a write error occurred
File: sh-utils.info,  Node: tty invocation,  Prev: printenv invocation,  Up: Working context information
`tty': Print file name of terminal on standard input
====================================================
   `tty' prints the file name of the tty connected to its standard
input.  It prints `not a tty' if standard input is not a tty.
   Synopsis:
     tty [ OPTION ]...
   The program accepts the following option.  Also see *Note Common
options::.
`--silent'
`--quiet'
     Print nothing; only return an exit status.
   Exit status:
     0 if standard input is a tty
     1 if standard input is not a tty
     2 if given incorrect arguments
     3 if a write error occurs
File: sh-utils.info,  Node: User information,  Next: System context,  Prev: Working context information,  Up: Top
User information
****************
   This section describes commands that print user-related information:
logins, groups, and so forth.
* Menu:
* id invocation::               Print real and effective uid and gid.
* logname invocation::          Print current login name.
* whoami invocation::           Print effective user id.
* groups invocation::           Print group names a user is in.
* users invocation::            Print login names of users currently logged in.
* who invocation::              Print who is currently logged in.
File: sh-utils.info,  Node: id invocation,  Next: logname invocation,  Up: User information
`id': Print real and effective uid and gid
==========================================
`id' prints information about the given user, or the process running it
if no user is specified.
   Synopsis:
     id [ OPTION ]... [ USERNAME ]
   By default, it prints the real user id, real group id, effective
user id if different from the real user id, effective group id if
different from the real group id, and supplemental group ids.
   Each of these numeric values is preceded by an identifying string and
followed by the corresponding user or group name in parentheses.
   The options cause `id' to print only part of the above information.
Also see *Note Common options::.
`--group'
     Print only the group id.
`--groups'
     Print only the supplementary groups.
`--name'
     Print the user or group name instead of the ID number.  Requires
     `-u', `-g', or `-G'.
`--real'
     Print the real, instead of effective, user or group id.  Requires
     `-u', `-g', or `-G'.
`--user'
     Print only the user id.
File: sh-utils.info,  Node: logname invocation,  Next: whoami invocation,  Prev: id invocation,  Up: User information
`logname': Print current login name
===================================
   `logname' prints the calling user's name, as found in the file
`/etc/utmp', and exits with a status of 0.  If there is no `/etc/utmp'
entry for the calling process, `logname' prints an error message and
exits with a status of 1.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: whoami invocation,  Next: groups invocation,  Prev: logname invocation,  Up: User information
`whoami': Print effective user id
=================================
   `whoami' prints the user name associated with the current effective
user id.  It is equivalent to the command `id -un'.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: groups invocation,  Next: users invocation,  Prev: whoami invocation,  Up: User information
`groups': Print group names a user is in
========================================
   `groups' prints the names of the primary and any supplementary
groups that each given USERNAME, or the current process if none are
given, is in.  If user names are given, the name of each user is
printed before the list of that user's groups.
   Synopsis:
     groups [ USERNAME ]...
   The group lists are equivalent to the output of the command `id -Gn'.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: users invocation,  Next: who invocation,  Prev: groups invocation,  Up: User information
`users': Print login names of users currently logged in
=======================================================
   `users' prints on a single line a blank-separated list of user names
of users currently logged in to the current host.  Each user name
corresponds to a login session, so if a user has more than one login
session, that user's name will appear the same number of times in the
output.
   Synopsis:
     users [ FILE ]
   With no FILE argument, `users' extracts its information from the
file `/etc/utmp'.  If a file argument is given, `users' uses that file
instead.  A common choice is `/etc/wtmp'.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: who invocation,  Prev: users invocation,  Up: User information
`who': Print who is currently logged in
=======================================
   Synopsis:
     `who' [ OPTION ] [ FILE ] [ am i ]
   If given no non-option arguments, `who' prints the following
information for each user currently logged on: login name, terminal
line, login time, and remote hostname or X display.
   If given one non-option argument, `who' uses that instead of
`/etc/utmp' as the name of the file containing the record of users
logged on.  `/etc/wtmp' is commonly given as an argument to `who' to
look at who has previously logged on.
   If given two non-option arguments, `who' prints only the entry for
the user running it (determined from its standard input), preceded by
the hostname.  Traditionally, the two arguments given are `am i', as in
`who am i'.
   The program accepts the following options.  Also see *Note Common
options::.
     Same as `who am i'.
`--count'
     Print only the login names and the number of users logged on.
     Overrides all other options.
     Ignored; for compatibility with other versions of `who'.
`--idle'
     After the login time, print the number of hours and minutes that
     the user has been idle.  `.' means the user was active in last
     minute.  `old' means the user was idle for more than 24 hours.
`--heading'
     Print a line of column headings.
`--mesg'
`--message'
`--writable'
     After each login name print a character indicating the user's
     message status:
          `+' allowing `write' messages
          `-' disallowing `write' messages
          `?' cannot find terminal device
File: sh-utils.info,  Node: System context,  Next: Modified command invocation,  Prev: User information,  Up: Top
System context
**************
   This section describes commands that print or change system-wide
information.
* Menu:
* date invocation::             Print or set system date and time.
* uname invocation::            Print system information.
* hostname invocation::         Print or set system name.
File: sh-utils.info,  Node: date invocation,  Next: uname invocation,  Up: System context
`date': Print or set system date and time
=========================================
   `date' with no arguments prints the current time and date, in the
format of the `%c' directive (described below).
   Synopses:
     date [ OPTION ]... [ +FORMAT ]
     date [ -u|--utc|--universal ] [ MMDDHHMM[[CC]YY][.SS] ]
   If given an argument that starts with a `+', `date' prints the
current time and date (or the time and date specified by the `--date'
option, see below) in the format defined by that argument, which is the
same as in the `strftime' function.  Except for directives, which start
with `%', characters in the format string are printed unchanged.  The
directives are described below.
   By default, `date' pads numeric fields with zeroes.  GNU `date'
recognizes the following numeric modifiers between the `%' and the
directive.  These are GNU extensions.
     (hyphen) do not pad the field
     (underscore) pad the field with spaces
* Menu:
* Time directives::             %[HIklMprsSTXZ]
* Date directives::             %[aAbBcdDhjmUwWxyY]
* Literal directives::          %[%nt]
* Setting the time::            Changing the system clock.
* Options for date::            Instead of the current time.
* Examples of date::            Examples.
File: sh-utils.info,  Node: Time directives,  Next: Date directives,  Up: date invocation
Time directives
---------------
   `date' directives related to times.
     hour (00...23)
     hour (01...12)
     hour ( 0...23)
     hour ( 1...12)
     minute (00...59)
     locale's AM or PM
     time, 12-hour (hh:mm:ss [AP]M)
     seconds since the epoch, i.e., 1 January 1970 00:00:00 UTC (a GNU
     extension)
     second (00...61)
     time, 24-hour (hh:mm:ss)
     locale's time representation (%H:%M:%S)
     time zone (e.g., EDT), or nothing if no time zone is determinable
File: sh-utils.info,  Node: Date directives,  Next: Literal directives,  Prev: Time directives,  Up: date invocation
Date directives
---------------
   `date' directives related to dates.
     locale's abbreviated weekday name (Sun...Sat)
     locale's full weekday name, variable length (Sunday...Saturday)
     locale's abbreviated month name (Jan...Dec)
     locale's full month name, variable length (January...December)
     locale's date and time (Sat Nov 04 12:02:33 EST 1989)
     day of month (01...31)
     date (mm/dd/yy)
     same as %b
     day of year (001...366)
     month (01...12)
     week number of year with Sunday as first day of week (00...53)
     day of week (0...6) with 0 corresponding to Sunday
     week number of year with Monday as first day of week (00...53)
     locale's date representation (mm/dd/yy)
     last two digits of year (00...99)
     year (1970....)
File: sh-utils.info,  Node: Literal directives,  Next: Setting the time,  Prev: Date directives,  Up: date invocation
Literal directives
------------------
   `date' directives that produce literal strings.
     a literal %
     a newline
     a horizontal tab
File: sh-utils.info,  Node: Setting the time,  Next: Options for date,  Prev: Literal directives,  Up: date invocation
Setting the time
----------------
   If given an argument that does not start with `+', `date' sets the
system clock to the time and date specified by that argument (as
described below).  You must have appropriate privileges to set the
system clock.  The `--date' and `--set' options may not be used with
such an argument.  The `--universal' option may be used with such an
argument to indicate that the specified time and date are relative to
Coordinated Universal Time rather than to the local time zone.
   The argument must consist entirely of digits, which have the
following meaning:
     month
     day within month
     hour
     minute
     first two digits of year (optional)
     last two digits of year (optional)
     second (optional)
   The `--set' option also sets the system clock; see the next section.
File: sh-utils.info,  Node: Options for date,  Next: Examples of date,  Prev: Setting the time,  Up: date invocation
Options for `date'
------------------
   The program accepts the following options.  Also see *Note Common
options::.
`-d DATESTR'
`--date=DATESTR'
     Display the time and date specified in DATESTR instead of the
     current time and date.  DATESTR can be in almost any common
     format.  It can contain month names, timezones, `am' and `pm',
     `yesterday', `ago', `next', etc.  The source file `getdate.y'
     implements this parsing for all GNU routines; we need precise
     documentation!
`-f DATEFILE'
`--file=DATEFILE'
     Parse each line in DATEFILE as with `-d' and display the resulting
     time and date.  If DATEFILE is `-', use standard input.  This is
     useful when you have many dates to process, because the system
     overhead of starting up the `date' executable many times can be
     considerable.
`-s DATESTR'
`--set=DATESTR'
     Set the time and date to DATESTR,  See `-d' above.
`--utc'
`--universal'
     Print or set the time and date in Universal Coordinated Time
     instead of in local (wall clock) time.
File: sh-utils.info,  Node: Examples of date,  Prev: Options for date,  Up: date invocation
Examples of `date'
------------------
   Here are a few examples.  Also see the documentation for the `-d'
option in the previous section.
   * To print the date of the day before yesterday:
          date --date='2 days ago'
   * To print the date of the day three months and one day hence:
          date --date='3 months 1 day'
   * To print the day of year of Christmas in the current year:
          date --date='25 Dec' +%j
   * To print the current full month name and the day of the month:
          date '+%B %d'
     But this may not be what you want because for the first nine days
     of the month, the `%d' expands to a zero-padded two-digit field,
     for example `date -d 1may '+%B %d'' will print `May 01'.
   * To print a date without the leading zero for one-digit days of the
     month, you can use the (GNU extension) `-' modifier to suppress
     the padding altogether.
          date -d=1may '+%B %-d'
   * To print the current date and time in the format required by many
     non-GNU versions of `date' when setting the system clock:
          date +%m%d%H%M%Y.%S
   * To set the system clock forward by two minutes:
          date --set='+2 minutes'
File: sh-utils.info,  Node: uname invocation,  Next: hostname invocation,  Prev: date invocation,  Up: System context
`uname': Print system information
=================================
   `uname' prints information about the machine and operating system it
is run on.  If no options are given, `uname' acts as if the `-s' option
were given.
   Synopsis:
     uname [ OPTION ]...
   If multiple options or `-a' are given, the selected information is
printed in this order:
     SYSNAME NODENAME RELEASE OSVERSION MACHINE
   The OSVERSION, at least, may well be multiple words.  For example:
     bash$ uname -a
     => Linux hayley 1.0.4 #3 Thu May 12 18:06:34 1994 i486
   The program accepts the following options.  Also see *Note Common
options::.
`--all'
     Print all of the below information.
`--machine'
     Print the machine (hardware) type.
`--nodename'
     Print the machine's network node hostname.
`--release'
     Print the operating system release.
`--sysname'
     Print the operating system name.
     Print the operating system version.
File: sh-utils.info,  Node: hostname invocation,  Prev: uname invocation,  Up: System context
`hostname': Print or set system name
====================================
   With no arguments, `hostname' prints the name of the current host
system.  With one argument, it sets the current host name to the
specified string.  You must have appropriate privileges to set the host
name.
   Synopsis:
     hostname [ NAME ]
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: Modified command invocation,  Next: Delaying,  Prev: System context,  Up: Top
Modified command invocation
***************************
   This section describes commands that run other commands in some
context different than the current one: a modified environment, as a
different user, etc.
* Menu:
* env invocation::              Modify environment variables.
* nice invocation::             Modify scheduling priority.
* nohup invocation::            Immunize to hangups.
* su invocation::               Modify user and group id.
File: sh-utils.info,  Node: env invocation,  Next: nice invocation,  Up: Modified command invocation
`env': Run a command in a modified environment
==============================================
   `env' runs a command with an environment modified as specified by
the command line arguments.
   Synopses:
     env [ OPTION ]... [ NAME=VALUE ]... [ COMMAND [ ARGS ]... ]
     env
   Arguments of the form `VARIABLE=VALUE' set the environment variable
VARIABLE to value VALUE.  VALUE may be empty (`VARIABLE=').  Setting a
variable to an empty value is different from unsetting it.
   The first remaining argument specifies the program name to invoke;
it is searched for according to the `PATH' environment variable.  Any
remaining arguments are passed as arguments to that program.
   If no command name is specified following the environment
specifications, the resulting environment is printed.  This is like
specifying a command name of `printenv'.
   The program accepts the following options.  Also see *Note Common
options::.
`-u NAME'
`--unset=NAME'
     Remove variable NAME from the environment, if it was in the
     environment.
`--ignore-environment'
     Start with an empty environment, ignoring the inherited
     environment.
File: sh-utils.info,  Node: nice invocation,  Next: nohup invocation,  Prev: env invocation,  Up: Modified command invocation
`nice': Run a command with modified scheduling priority
=======================================================
   If no arguments are given, `nice' prints the current scheduling
priority, which it inherited.  Otherwise, `nice' runs the given COMMAND
with its scheduling priority adjusted.  If no ADJUSTMENT is given, the
priority of the command is incremented by 10.  You must have
appropriate privileges to specify a negative adjustment.  The priority
can be adjusted by `nice' over the range of -20 (the highest priority)
to 19 (the lowest).
   Synopsis:
     nice [ OPTION ]... [ COMMAND [ ARG ]... ]
   Because most shells have a built-in command by the same name, using
the unadorned command name in a script or interactively may get you
different functionality than that described here.
   The program accepts the following option.  Also see *Note Common
options::.
`-n ADJUSTMENT'
`-ADJUSTMENT'
`--adjustment=ADJUSTMENT'
     Add ADJUSTMENT instead of 10 to the command's priority.
File: sh-utils.info,  Node: nohup invocation,  Next: su invocation,  Prev: nice invocation,  Up: Modified command invocation
`nohup': Run a command immune to hangups
========================================
   `nohup' runs the given COMMAND with hangup signals ignored, so that
the command can continue running in the background after you log out.
   Synopsis:
     nohup COMMAND [ ARG ]...
   Also, the scheduling priority is increased by 5.  If standard output
is a tty, it and standard error are redirected so that they are
appended to the file `nohup.out'; if that cannot be written to, they are
appended to the file `$HOME/nohup.out'.  If that cannot be written to,
the command is not run.
   If `nohup' creates either `nohup.out' or `$HOME/nohup.out', it
creates it with no "group" or "other" access permissions.  It does not
change the permissions if the output file already existed.
   `nohup' does not automatically put the command it runs in the
background; you must do that explicitly, by ending the command line
with an `&'.
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: su invocation,  Prev: nohup invocation,  Up: Modified command invocation
`su': Run a command with substitute user and group id
=====================================================
   `su' allows one user to temporarily become another user.  It runs a
command (often an interactive shell) with the real and effective user
id, group id, and supplemental groups of a given USER.
   Synopsis:
     su [ OPTION ]... [ USER [ ARG ]... ]
   If no USER is given, the default is `root', the super-user.  The
shell to use is taken from USER's `passwd' entry, or `/bin/sh' if none
is specified there.  If USER has a password, `su' prompts for the
password unless run by a user with effective user id of zero (the
super-user).
   By default, `su' does not change the current directory.  It sets the
environment variables `HOME' and `SHELL' from the password entry for
USER, and if USER is not the super-user, sets `USER' and `LOGNAME' to
USER.  By default, the shell is not a login shell.
   Any additional ARGs are passed as additional arguments to the shell.
   GNU `su' does not treat `/bin/sh' or any other shells specially
(e.g., by setting `argv[0]' to `-su', passing `-c' only to certain
shells, etc.).
   `su' can optionally be compiled to use `syslog' to report failed,
and optionally successful, `su' attempts.  (If the system supports
`syslog'.)  However, GNU `su' does not check if the user is a member of
the `wheel' group; see below.
   The program accepts the following options.  Also see *Note Common
options::.
`-c COMMAND'
`--command=COMMAND'
     Pass COMMAND, a single command line to run, to the shell with a
     `-c' option instead of starting an interactive shell.
`--fast'
     Pass the `-f' option to the shell.  This probably only makes sense
     if the shell run is `csh' or `tcsh', for which the `-f' option
     prevents reading the startup file (`.cshrc').  With Bourne-like
     shells, the `-f' option disables file name pattern expansion
     (globbing), which is not likely to be useful.
`--login'
     Make the shell a login shell.  This means the following.  Unset all
     environment variables except `TERM', `HOME', and `SHELL' (which
     are set as described above), and `USER' and `LOGNAME' (which are
     set, even for the super-user, as described above), and set `PATH'
     to a compiled-in default value.  Change to USER's home directory.
     Prepend `-' to the shell's name, intended to make it read its
     login startup file(s).
`--preserve-environment'
     Do not change the environment variables `HOME', `USER', `LOGNAME',
     or `SHELL'.  Run the shell given in the environment variable
     `SHELL' instead of the shell from USER's passwd entry, unless the
     user running `su' is not the superuser and USER's shell is
     restricted.  A "restricted shell" is one that is not listed in the
     file `/etc/shells', or in a compiled-in list if that file does not
     exist.  Parts of what this option does can be overridden by
     `--login' and `--shell'.
`-s SHELL'
`--shell=SHELL'
     Run SHELL instead of the shell from USER's passwd entry, unless
     the user running `su' is not the superuser and USER's shell is
     restricted (see `-m' just above).
Why GNU `su' does not support the `wheel' group
===============================================
   (This section is by Richard Stallman.)
   Sometimes a few of the users try to hold total power over all the
rest.  For example, in 1984, a few users at the MIT AI lab decided to
seize power by changing the operator password on the Twenex system and
keeping it secret from everyone else.  (I was able to thwart this coup
and give power back to the users by patching the kernel, but I wouldn't
know how to do that in Unix.)
   However, occasionally the rulers do tell someone.  Under the usual
`su' mechanism, once someone learns the root password who sympathizes
with the ordinary users, he or she can tell the rest.  The "wheel
group" feature would make this impossible, and thus cement the power of
the rulers.
   I'm on the side of the masses, not that of the rulers.  If you are
used to supporting the bosses and sysadmins in whatever they do, you
might find this idea strange at first.
File: sh-utils.info,  Node: Delaying,  Next: Index,  Prev: Modified command invocation,  Up: Top
Delaying
********
   Perhaps `wait' or other commands should be described here also?
* Menu:
* sleep invocation::            Delay for a specified time.
File: sh-utils.info,  Node: sleep invocation,  Up: Delaying
`sleep': Delay for a specified time
===================================
   `sleep' pauses for an amount of time specified by the sum of the
values of the command line arguments.
   Synopsis:
     sleep [ NUMBER[smhd] ]...
   Each argument is a number followed by an optional unit; the default
is seconds.  The units are:
     seconds
     minutes
     hours
     days
   The only options are `--help' and `--version'.  *Note Common
options::.
File: sh-utils.info,  Node: Index,  Prev: Delaying,  Up: Top
Index
*****
* Menu:
* !:                                    Connectives for test.
* !=:                                   String tests.
* %:                                    Numeric expressions.
* &:                                    Relations for expr.
* *:                                    Numeric expressions.
* +:                                    Numeric expressions.
* -:                                    Numeric expressions.
* -:                                    env invocation.
* -:                                    su invocation.
* -adjustment:                          nice invocation.
* -all:                                 stty invocation.
* -all:                                 uname invocation.
* -append:                              tee invocation.
* -command:                             su invocation.
* -count:                               who invocation.
* -date:                                Options for date.
* -fast:                                su invocation.
* -file:                                Options for date.
* -group:                               id invocation.
* -groups:                              id invocation.
* -heading:                             who invocation.
* -help:                                Common options.
* -idle:                                who invocation.
* -ignore-environment:                  env invocation.
* -ignore-interrupts:                   tee invocation.
* -login:                               su invocation.
* -machine:                             uname invocation.
* -mesg:                                who invocation.
* -message:                             who invocation.
* -name:                                id invocation.
* -nodename:                            uname invocation.
* -portability:                         pathchk invocation.
* -preserve-environment:                su invocation.
* -quiet:                               tty invocation.
* -real:                                id invocation.
* -release:                             uname invocation.
* -save:                                stty invocation.
* -set:                                 Options for date.
* -shell:                               su invocation.
* -silent:                              tty invocation.
* -sysname:                             uname invocation.
* -universal:                           Options for date.
* -user:                                id invocation.
* -utc:                                 Options for date.
* -version:                             Common options.
* -writable:                            who invocation.
* -ADJUSTMENT:                          nice invocation.
* -a:                                   uname invocation.
* -a:                                   tee invocation.
* -a:                                   Connectives for test.
* -a:                                   stty invocation.
* -b:                                   File type tests.
* -c:                                   File type tests.
* -c:                                   su invocation.
* -d:                                   Options for date.
* -d:                                   File type tests.
* -e:                                   File characteristics tests.
* -e:                                   echo invocation.
* -ef:                                  File characteristics tests.
* -eq:                                  Numeric tests.
* -f:                                   Options for date.
* -f:                                   su invocation.
* -f:                                   File type tests.
* -g:                                   Access permission tests.
* -G:                                   id invocation.
* -G:                                   Access permission tests.
* -g:                                   id invocation.
* -g:                                   stty invocation.
* -ge:                                  Numeric tests.
* -gt:                                  Numeric tests.
* -h:                                   File type tests.
* -H:                                   who invocation.
* -i:                                   tee invocation.
* -i:                                   who invocation.
* -i:                                   env invocation.
* -k:                                   Access permission tests.
* -L:                                   File type tests.
* -l:                                   su invocation.
* -le:                                  Numeric tests.
* -lt:                                  Numeric tests.
* -m:                                   su invocation.
* -m:                                   who invocation.
* -m:                                   uname invocation.
* -n:                                   String tests.
* -n:                                   echo invocation.
* -n:                                   id invocation.
* -n:                                   uname invocation.
* -n:                                   nice invocation.
* -ne:                                  Numeric tests.
* -nt:                                  File characteristics tests.
* -O:                                   Access permission tests.
* -o:                                   Connectives for test.
* -ot:                                  File characteristics tests.
* -p:                                   su invocation.
* -p:                                   File type tests.
* -p:                                   pathchk invocation.
* -q:                                   who invocation.
* -r:                                   id invocation.
* -r:                                   Access permission tests.
* -r:                                   uname invocation.
* -s:                                   File characteristics tests.
* -s:                                   who invocation.
* -S:                                   File type tests.
* -s:                                   uname invocation.
* -s:                                   Options for date.
* -s:                                   su invocation.
* -s:                                   tty invocation.
* -t:                                   File type tests.
* -T:                                   who invocation.
* -u:                                   Options for date.
* -u:                                   env invocation.
* -u:                                   Access permission tests.
* -u:                                   who invocation.
* -u:                                   id invocation.
* -unset:                               env invocation.
* -v:                                   uname invocation.
* -w:                                   who invocation.
* -w:                                   Access permission tests.
* -x:                                   Access permission tests.
* -z:                                   String tests.
* .cshrc:                               su invocation.
* /:                                    Numeric expressions.
* /bin/sh:                              su invocation.
* /etc/passwd:                          su invocation.
* /etc/shells:                          su invocation.
* /etc/utmp:                            who invocation.
* /etc/utmp:                            users invocation.
* /etc/utmp:                            logname invocation.
* /etc/wtmp:                            users invocation.
* /etc/wtmp:                            who invocation.
* <:                                    Relations for expr.
* <=:                                   Relations for expr.
* =:                                    String tests.
* =:                                    Relations for expr.
* ==:                                   Relations for expr.
* >:                                    Relations for expr.
* >=:                                   Relations for expr.
* date options:                         Options for date.
* -su:                                  su invocation.
* access permission tests:              Access permission tests.
* addition:                             Numeric expressions.
* am i:                                 who invocation.
* and operator:                         Connectives for test.
* and operator:                         Relations for expr.
* appropriate privileges:               hostname invocation.
* appropriate privileges:               nice invocation.
* appropriate privileges:               Setting the time.
* arbitrary date strings, parsing:      Options for date.
* arbitrary text, displaying:           echo invocation.
* arithmetic tests:                     Numeric tests.
* background jobs, stopping at terminal write: Local.
* backslash escapes:                    echo invocation.
* basename:                             basename invocation.
* baud rate, setting:                   Special.
* beeping at input buffer full:         Input.
* beginning of time:                    Time directives.
* block special check:                  File type tests.
* breaks, cause interrupts:             Input.
* breaks, ignoring:                     Input.
* brkint:                               Input.
* bsN:                                  Output.
* bugs, reporting:                      Introduction.
* built-in shell commands, conflicts with: nice invocation.
* built-in shell commands, conflicts with: pwd invocation.
* built-in shell commands, conflicts with: test invocation.
* C-s/C-q flow control:                 Input.
* case translation:                     Local.
* cbreak:                               Combination.
* change or print terminal settings:    stty invocation.
* character size:                       Control.
* character special check:              File type tests.
* characters, special:                  Characters.
* check file types:                     test invocation.
* clocal:                               Control.
* cols:                                 Special.
* columns:                              Special.
* COLUMNS:                              Special.
* combination settings:                 Combination.
* commands for delaying:                Delaying.
* commands for exit status:             Conditions.
* commands for file name manipulation:  File name manipulation.
* commands for invoking other commands: Modified command invocation.
* commands for printing text:           Printing text.
* commands for printing the working context: Working context information.
* commands for printing user information: User information.
* commands for redirection:             Redirection.
* commands for system context:          System context.
* common options:                       Common options.
* compare values:                       test invocation.
* comparison operators:                 Relations for expr.
* conditions:                           Conditions.
* conflicts with shell built-ins:       nice invocation.
* conflicts with shell built-ins:       pwd invocation.
* conflicts with shell built-ins:       test invocation.
* connectives, logical:                 Relations for expr.
* connectives, logical:                 Connectives for test.
* context, system:                      System context.
* control characters, using ^C:         Local.
* control settings:                     Control.
* cooked:                               Combination.
* coordinated universal time:           Options for date.
* crN:                                  Output.
* cread:                                Control.
* crt:                                  Combination.
* crterase:                             Local.
* crtkill:                              Local.
* crtscts:                              Control.
* csN:                                  Control.
* cstopb:                               Control.
* ctlecho:                              Local.
* current working directory, printing:  pwd invocation.
* date:                                 date invocation.
* date directives:                      Date directives.
* date strings, parsing:                Options for date.
* dec:                                  Combination.
* decctlq:                              Combination.
* delay for a specified time:           sleep invocation.
* delaying commands:                    Delaying.
* destinations, multiple output:        tee invocation.
* directives, date:                     Date directives.
* directives, literal:                  Literal directives.
* directives, time:                     Time directives.
* directory check:                      File type tests.
* directory components, printing:       dirname invocation.
* directory, stripping from file names: basename invocation.
* dirname:                              dirname invocation.
* disabling special characters:         Characters.
* displaying text:                      echo invocation.
* division:                             Numeric expressions.
* do nothing, successfully:             true invocation.
* dsusp:                                Characters.
* echo:                                 Local.
* echo:                                 echo invocation.
* echoctl:                              Local.
* echoe:                                Local.
* echok:                                Local.
* echoke:                               Local.
* echonl:                               Local.
* echoprt:                              Local.
* effective uid and gid, printing:      id invocation.
* effective UID, printing:              whoami invocation.
* eight-bit characters:                 Combination.
* eight-bit characters:                 Control.
* eight-bit input:                      Input.
* ek:                                   Combination.
* env:                                  env invocation.
* environment variables, printing:      printenv invocation.
* environment, preserving:              su invocation.
* environment, printing:                env invocation.
* environment, running a program in a modified: env invocation.
* eof:                                  Characters.
* eol:                                  Characters.
* eol2:                                 Characters.
* epoch, seconds since:                 Time directives.
* equal string check:                   String tests.
* erase:                                Characters.
* evaluation of expressions:            expr invocation.
* even parity:                          Control.
* evenp:                                Combination.
* examples of date:                     Examples of date.
* examples of expr:                     Examples of expr.
* executable file check:                Access permission tests.
* existence-of-file check:              File characteristics tests.
* exit status commands:                 Conditions.
* exit status of expr:                  expr invocation.
* exit status of pathchk:               pathchk invocation.
* exit status of printenv:              printenv invocation.
* exit status of true:                  true invocation.
* exit status of true:                  false invocation.
* exit status of tty:                   tty invocation.
* expr:                                 expr invocation.
* expression evaluation:                test invocation.
* expression evaluation:                expr invocation.
* expressions, numeric:                 Numeric expressions.
* expressions, string:                  String expressions.
* failure exit status:                  false invocation.
* false:                                false invocation.
* fascism:                              su invocation.
* ffN:                                  Output.
* fields, padding numeric:              date invocation.
* file characteristics tests:           File characteristics tests.
* file name manipulation:               File name manipulation.
* file name pattern expansion, disabled: su invocation.
* file names, checking validity and portability: pathchk invocation.
* file names, stripping directory and suffix: basename invocation.
* file type tests:                      File type tests.
* flow control, hardware:               Control.
* flow control, software:               Input.
* flushing, disabling:                  Local.
* formatting times:                     date invocation.
* getdate.y:                            Options for date.
* globbing, disabled:                   su invocation.
* Greenwich Mean Time:                  Options for date.
* group wheel, not supported:           su invocation.
* groups:                               groups invocation.
* hangups, immunity to:                 nohup invocation.
* hard link check:                      File characteristics tests.
* hardware flow control:                Control.
* hardware type:                        uname invocation.
* hat notation for control characters:  Local.
* help, online:                         Common options.
* history:                              Introduction.
* HOME:                                 su invocation.
* hostname:                             hostname invocation.
* hostname:                             uname invocation.
* hup[cl]:                              Control.
* icanon:                               Local.
* icrnl:                                Input.
* id:                                   id invocation.
* idle time:                            who invocation.
* iexten:                               Local.
* ignbrk:                               Input.
* igncr:                                Input.
* ignpar:                               Input.
* imaxbel:                              Input.
* immunity to hangups:                  nohup invocation.
* index:                                String expressions.
* information, about current users:     who invocation.
* inlcr:                                Input.
* inpck:                                Input.
* input settings:                       Input.
* intr:                                 Characters.
* introduction:                         Introduction.
* invocation of commands, modified:     Modified command invocation.
* isig:                                 Local.
* ispeed:                               Special.
* istrip:                               Input.
* iuclc:                                Input.
* ixany:                                Input.
* ixoff:                                Input.
* ixon:                                 Input.
* kill:                                 Characters.
* last DAY:                             Options for date.
* LCASE:                                Combination.
* lcase:                                Combination.
* leading directory components, stripping: basename invocation.
* length:                               String expressions.
* line:                                 Special.
* line settings of terminal:            stty invocation.
* LINES:                                Special.
* literal directives:                   Literal directives.
* litout:                               Combination.
* lnext:                                Characters.
* local settings:                       Local.
* logical and operator:                 Relations for expr.
* logical and operator:                 Connectives for test.
* logical connectives:                  Relations for expr.
* logical connectives:                  Connectives for test.
* logical or operator:                  Relations for expr.
* logical or operator:                  Connectives for test.
* login name, printing:                 logname invocation.
* login sessions, printing users with:  users invocation.
* login shell:                          su invocation.
* login shell, creating:                su invocation.
* login time:                           who invocation.
* logname:                              logname invocation.
* LOGNAME:                              su invocation.
* lowercase, translating to output:     Output.
* machine type:                         uname invocation.
* machine-readable stty output:         stty invocation.
* manipulation of file names:           File name manipulation.
* match:                                String expressions.
* matching patterns:                    String expressions.
* message status:                       who invocation.
* min:                                  Special.
* MIT AI lab:                           su invocation.
* modem control:                        Control.
* modified command invocation:          Modified command invocation.
* modified environment, running a program in: env invocation.
* modifying scheduling priority:        nice invocation.
* multiplication:                       Numeric expressions.
* name of operating system:             uname invocation.
* named pipe check:                     File type tests.
* network node name:                    uname invocation.
* newer-than file check:                File characteristics tests.
* newline echoing after kill:           Local.
* newline, echoing:                     Local.
* newline, translating to crlf:         Output.
* newline, translating to return:       Input.
* next DAY:                             Options for date.
* nice:                                 nice invocation.
* nl:                                   Combination.
* nlN:                                  Output.
* no-op:                                true invocation.
* node name:                            uname invocation.
* noflsh:                               Local.
* nohup:                                nohup invocation.
* nohup.out:                            nohup invocation.
* nohup.out:                            nohup invocation.
* non-directory suffix, stripping:      dirname invocation.
* nonempty file check:                  File characteristics tests.
* nonzero-length string check:          String tests.
* not-equal string check:               String tests.
* numeric expressions:                  Numeric expressions.
* numeric field padding:                date invocation.
* numeric tests:                        Numeric tests.
* ocrnl:                                Output.
* odd parity:                           Control.
* oddp:                                 Combination.
* ofdel:                                Output.
* ofill:                                Output.
* olcuc:                                Output.
* older-than file check:                File characteristics tests.
* onlcr:                                Output.
* onlret:                               Output.
* onocr:                                Output.
* operating system name:                uname invocation.
* operating system release:             uname invocation.
* operating system version:             uname invocation.
* opost:                                Output.
* options for date:                     Options for date.
* or operator:                          Relations for expr.
* or operator:                          Connectives for test.
* ospeed:                               Special.
* output settings:                      Output.
* owned by effective gid check:         Access permission tests.
* owned by effective uid check:         Access permission tests.
* pad character:                        Output.
* pad instead of timing for delaying:   Output.
* padding of numeric fields:            date invocation.
* parenb:                               Control.
* parentheses for grouping:             expr invocation.
* parity:                               Combination.
* parity errors, marking:               Input.
* parity, ignoring:                     Input.
* parmrk:                               Input.
* parodd:                               Control.
* parsing date strings:                 Options for date.
* pass8:                                Combination.
* passwd entry, and su shell:           su invocation.
* PATH:                                 env invocation.
* PATH:                                 su invocation.
* pathchk:                              pathchk invocation.
* pattern matching:                     String expressions.
* permission tests:                     Access permission tests.
* pipe fitting:                         tee invocation.
* portable file names, checking for:    pathchk invocation.
* POSIX.2:                              Introduction.
* print name of current directory:      pwd invocation.
* print system information:             uname invocation.
* print terminal file name:             tty invocation.
* printenv:                             printenv invocation.
* printf:                               printf invocation.
* printing all or some environment variables: printenv invocation.
* printing current user information:    who invocation.
* printing current usernames:           users invocation.
* printing groups a user is in:         groups invocation.
* printing real and effective uid and gid: id invocation.
* printing text:                        echo invocation.
* printing text, commands for:          Printing text.
* printing the current time:            date invocation.
* printing the effective UID:           whoami invocation.
* printing the hostname:                hostname invocation.
* printing user's login name:           logname invocation.
* priority, modifying:                  nice invocation.
* prterase:                             Local.
* pwd:                                  pwd invocation.
* quit:                                 Characters.
* raw:                                  Combination.
* read from stdin and write to stdout and files: tee invocation.
* readable file check:                  Access permission tests.
* real uid and gid, printing:           id invocation.
* redirection:                          Redirection.
* regular expression matching:          String expressions.
* regular file check:                   File type tests.
* relations, numeric or string:         Relations for expr.
* release of operating system:          uname invocation.
* remainder:                            Numeric expressions.
* remote hostname:                      who invocation.
* repeated output of a string:          yes invocation.
* restricted shell:                     su invocation.
* return, ignoring:                     Input.
* return, translating to newline:       Output.
* return, translating to newline:       Input.
* root, becoming:                       su invocation.
* rows:                                 Special.
* rprnt:                                Characters.
* RTS/CTS flow control:                 Control.
* same file check:                      File characteristics tests.
* sane:                                 Combination.
* scheduling priority, modifying:       nice invocation.
* seconds since the epoch:              Time directives.
* set-group-id check:                   Access permission tests.
* set-user-id check:                    Access permission tests.
* setting the hostname:                 hostname invocation.
* setting the time:                     Setting the time.
* SHELL:                                su invocation.
* shell utilities:                      Top.
* size:                                 Special.
* sleep:                                sleep invocation.
* socket check:                         File type tests.
* software flow control:                Input.
* special characters:                   Characters.
* special settings:                     Special.
* speed:                                Special.
* start:                                Characters.
* sticky bit check:                     Access permission tests.
* stop:                                 Characters.
* stop bits:                            Control.
* strftime and date:                    date invocation.
* string expressions:                   String expressions.
* string tests:                         String tests.
* strip directory and suffix from file names: basename invocation.
* stripping non-directory suffix:       dirname invocation.
* stty:                                 stty invocation.
* su:                                   su invocation.
* substitute user and group ids:        su invocation.
* substr:                               String expressions.
* subtraction:                          Numeric expressions.
* successful exit:                      true invocation.
* suffix, stripping from file names:    basename invocation.
* super-user, becoming:                 su invocation.
* supplementary groups, printing:       groups invocation.
* susp:                                 Characters.
* swtch:                                Characters.
* symbolic link check:                  File type tests.
* symbolic links and pwd:               pwd invocation.
* syslog:                               su invocation.
* system context:                       System context.
* system information, printing:         uname invocation.
* system name, printing:                hostname invocation.
* tabN:                                 Output.
* tabs:                                 Combination.
* tandem:                               Input.
* tee:                                  tee invocation.
* TERM:                                 su invocation.
* terminal check:                       File type tests.
* terminal file name, printing:         tty invocation.
* terminal lines, currently used:       who invocation.
* terminal settings:                    stty invocation.
* test:                                 test invocation.
* text, displaying:                     echo invocation.
* time:                                 Special.
* time directives:                      Time directives.
* time formats:                         date invocation.
* time setting:                         Setting the time.
* time units:                           sleep invocation.
* time, printing or setting:            date invocation.
* tomorrow:                             Options for date.
* tostop:                               Local.
* true:                                 true invocation.
* tty:                                  tty invocation.
* Twenex:                               su invocation.
* two-way parity:                       Control.
* u, and disabling special characters:  Characters.
* uname:                                uname invocation.
* uppercase, translating to lowercase:  Input.
* USER:                                 su invocation.
* user id, switching:                   su invocation.
* user information, commands for:       User information.
* user name, printing:                  logname invocation.
* usernames, printing current:          users invocation.
* users:                                users invocation.
* utilities for shell programming:      Top.
* utmp:                                 logname invocation.
* valid file names, checking for:       pathchk invocation.
* version number, finding:              Common options.
* version of operating system:          uname invocation.
* vtN:                                  Output.
* werase:                               Characters.
* wheel group, not supported:           su invocation.
* who:                                  who invocation.
* who am i:                             who invocation.
* whoami:                               whoami invocation.
* working context:                      Working context information.
* working directory, printing:          pwd invocation.
* writable file check:                  Access permission tests.
* write, allowed:                       who invocation.
* xcase:                                Local.
* XON/XOFF flow control:                Input.
* yes:                                  yes invocation.
* yesterday:                            Options for date.
* zero-length string check:             String tests.
* \0ooo:                                printf invocation.
* \0xhhh:                               printf invocation.
* \c:                                   printf invocation.
* |:                                    Relations for expr.
Tag Table:
Node: Top
Node: Introduction
Node: Common options
Node: Printing text
Node: echo invocation
Node: printf invocation
Node: yes invocation
Node: Conditions
Node: false invocation
Node: true invocation
Node: test invocation
10144
Node: File type tests
11284
Node: Access permission tests
12075
Node: File characteristics tests
12840
Node: String tests
13507
Node: Numeric tests
14089
Node: Connectives for test
14873
Node: expr invocation
15213
Node: Relations for expr
16354
Node: Numeric expressions
17048
Node: String expressions
17646
Node: Examples of expr
19350
Node: Redirection
19932
Node: tee invocation
20373
Node: File name manipulation
21201
Node: basename invocation
21657
Node: dirname invocation
22221
Node: pathchk invocation
22735
Node: Working context information
23898
Node: pwd invocation
24574
Node: stty invocation
25186
Node: Control
27095
Node: Input
27843
Node: Output
29200
Node: Local
30444
Node: Combination
32011
Node: Characters
34149
Node: Special
35689
Node: printenv invocation
37027
Node: tty invocation
37750
Node: User information
38445
Node: id invocation
39105
Node: logname invocation
40248
Node: whoami invocation
40751
Node: groups invocation
41145
Node: users invocation
41791
Node: who invocation
42603
Node: System context
44320
Node: date invocation
44743
Node: Time directives
46107
Node: Date directives
46761
Node: Literal directives
47758
Node: Setting the time
48042
Node: Options for date
49017
Node: Examples of date
50197
Node: uname invocation
51482
Node: hostname invocation
52587
Node: Modified command invocation
53086
Node: env invocation
53653
Node: nice invocation
54916
Node: nohup invocation
56042
Node: su invocation
57165
Node: Delaying
61441
Node: sleep invocation
61698
Node: Index
62230
End Tag Table