SysIII/usr/src/man/man1/getopt.1

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.TH GETOPT 1
.SH NAME
getopt \- parse command options
.SH SYNOPSIS
.B set \-\- \*`getopt optstring $\(**\*`
.SH DESCRIPTION
.I Getopt\^
is used to break up options in command lines for easy parsing by shell
procedures, and to check for legal options.
.I 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 \fB\-\-\fP is used to delimit the end of the
options.
.I Getopt\^
will place \fB\-\-\fP 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 \fB\-\fP and in its own shell argument; each option
argument is also in its own shell argument.
.SH DIAGNOSTICS
.I Getopt\^
prints an error message on
the standard error
when it encounters an option letter not included in
.IR optstring .
.SH EXAMPLE
The following code fragment shows how one might process the arguments
for a command that can take the options
.B a
and
.BR b ,
and the option
.BR o ,
which requires an argument.
.PP
.RS
.nf
.ss 18
set \-\- \*`getopt abo: $\(**\*`
if [ $? != 0 ]
then
	echo $USAGE
	exit 2
fi
for i in $\(**
do
	case $i in
	\-a \(bv \-b)	FLAG=$i; shift;;
	\-o)		OARG=$2;	shift; shift;;
	\-\-)		shift;	break;;
	esac
done
.fi
.ss 12
.RE
.PP
This code will accept any of the following as equivalent:
.PP
.RS
.nf
.ss 18
cmd \-aoarg file file
cmd \-a \-o arg file file
cmd \-oarg \-a file file
cmd \-a \-oarg \-\- file file
.fi
.ss 12
.RE
.SH SEE ALSO
sh(1),
getopt(3C).