getoptprog

SYNOPSIS

     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 fol-
     lowed 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.

EXAMPLE

     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 [o],
     which requires an argument.

           set -- `getopt abo: $*`
           if test $? != 0
           then
                   echo 'Usage: ...'
                   exit 2
           fi
           for i
           do
                   case "$i"
                   in
                           -a|-b)
                                   flag=$i; shift;;
                           -o)
                                   oarg=$2; shift; shift;;
                           --)
                                   shift; break;;
                   esac
           done

     This code will accept any of the following as equivalent:

           cmd -aoarg file file
           cmd -a -o arg file file
           cmd -oarg -a file file
           cmd -a -oarg -- file file

SEE ALSO

     sh(1),  getopt(3)

DIAGNOSTICS

     Getopt prints an error message on the standard error output when it en-
     counters an option letter not included in [optstring].

HISTORY

     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 version to
     another.  varies from one shell version to another.

BSD Experimental                 June 21, 1993                               2