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getopt(1) [netbsd man page]

GETOPT(1)						    BSD General Commands Manual 						 GETOPT(1)

NAME
getopt -- parse command options SYNOPSIS
args=`getopt optstring $*` set -- `getopt optstring $*` DESCRIPTION
getopt is used to break up options in command lines for easy parsing by shell procedures, and to check for legal options. [Optstring] is a string of recognized option letters (see getopt(3)); if a letter is followed by a colon, the option is expected to have an argument which may or may not be separated from it by white space. The special option ``--'' is used to delimit the end of the options. getopt will place ``--'' in the arguments at the end of the options, or recognize it if used explicitly. The shell arguments ($1, $2, ...) are reset so that each option is preceded by a ``-'' and in its own shell argument; each option argument is also in its own shell argument. getopt should not be used in new scripts; use the shell builtin getopts instead. EXAMPLES
The following code fragment shows how one might process the arguments for a command that can take the options [a] and [b], and the option [c], which requires an argument. args=`getopt abc: $*` if [ $? -ne 0 ]; then echo 'Usage: ...' exit 2 fi set -- $args while [ $# -gt 0 ]; do case "$1" in -a|-b) flag=$1 ;; -c) carg=$2; shift ;; --) shift; break ;; esac shift done This code will accept any of the following as equivalent: cmd -acarg file file cmd -a -c arg file file cmd -carg -a file file cmd -a -carg -- file file IEEE Std 1003.2 (``POSIX.2'') mandates that the sh(1) set command return the value of 0 for the exit status. Therefore, the exit status of the getopt command is lost when getopt and the sh(1) set command are used on the same line. The example given is one way to detect errors found by getopt. DIAGNOSTICS
getopt prints an error message on the standard error output when it encounters an option letter not included in [optstring]. SEE ALSO
sh(1), getopt(3) HISTORY
Written by Henry Spencer, working from a Bell Labs manual page. Behavior believed identical to the Bell version. BUGS
Whatever getopt(3) has. Arguments containing white space or embedded shell metacharacters generally will not survive intact; this looks easy to fix but isn't. The error message for an invalid option is identified as coming from getopt rather than from the shell procedure containing the invocation of getopt; this again is hard to fix. The precise best way to use the set command to set the arguments without disrupting the value(s) of shell options varies from one shell ver- sion to another. BSD
November 28, 2009 BSD

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getopt(1)							   User Commands							 getopt(1)

NAME
getopt - parse command options SYNOPSIS
set -- ` getopt optstring $ * ` DESCRIPTION
The getopts command supersedes getopt. For more information, see NOTES below. getopt is used to break up options in command lines for easy parsing by shell procedures and to check for legal options. optstring is a string of recognized option letters; see getopt(3C). If a letter is followed by a colon (:), the option is expected to have an argument which may or may not be separated from it by white space. The special option - is used to delimit the end of the options. If it is used explicitly, getopt recognizes it; otherwise, getopt generates it; in either case, getopt places it at the end of the options. The posi- tional parameters ($1 $2 ...) of the shell are reset so that each option is preceded by a - and is in its own positional parameter; each option argument is also parsed into its own positional parameter. EXAMPLES
Example 1: Processing the arguments for a command The following code fragment shows how one might process the arguments for a command that can take the options -a or -b, as well as the option -o, which requires an argument: set -- `getopt abo: $*` if [ $? != 0 ] then echo $USAGE exit 2 fi for i in $* do case $i in -a | -b) FLAG=$i; shift;; -o) OARG=$2; shift 2;; --) shift; break;; esac done This code accepts any of the following as equivalent: cmd -aoarg filename1 filename2 cmd -a -o arg filename1 filename2 cmd -oarg -a filename1 filename2 cmd -a -oarg -- filename1 filename2 ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |CSI |enabled | +-----------------------------+-----------------------------+ SEE ALSO
intro(1), getopts(1), getoptcvt(1), sh(1), shell_builtins(1), getopt(3C), attributes(5) DIAGNOSTICS
getopt prints an error message on the standard error when it encounters an option letter not included in optstring. NOTES
getopt will not be supported in the next major release. For this release a conversion tool has been provided, namely, getoptcvt. For more information, see getopts(1) and getoptcvt(1). Reset optind to 1 when rescanning the options. getopt does not support the part of Rule 8 of the command syntax standard (see intro(1)) that permits groups of option-arguments following an option to be separated by white space and quoted. For example, cmd -a -b -o "xxx z yy" filename is not handled correctly. To correct this deficiency, use the getopts command in place of getopt. If an option that takes an option-argument is followed by a value that is the same as one of the options listed in optstring (referring to the earlier EXAMPLES section, but using the following command line: cmd -o -a filename getopt always treats it as an option-argument to -o; it never recognizes -a as an option. For this case, the for loop in the example shifts past the filename argument. SunOS 5.10 7 Jan 2000 getopt(1)
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