NAME

getopt − Parses command line flags and arguments

SYNOPSIS

getopt format tokens

DESCRIPTION

The getopt command is used to parse a list of tokens using a format that specifies expected flags and arguments.  A flag is a single ASCII letter and, when followed by a : (colon), is expected to take a modifying argument that may or may not be separated from it by one or more tabs or spaces.  (You can include multi-byte characters in arguments, but not as flag letters.) 

The getopt command completes processing when it has read all tokens or when it encounters the special token -- (double dash).  It then outputs the processed flags, a --, and any remaining tokens. 

If a token fails to match a flag, getopt writes a message to standard error. 

NOTES

In the csh, use the following command to run getopt:

set argv=‘getopt flag_string $∗‘

EXAMPLES

The following is an example of the use of getopt in a skeleton shell script to parse options:

#!/bin/sh
# parse command line into arguments
set -- ‘getopt a:bc $∗‘
# check result of parsing
if [ $? != 0 ]
then
        exit 1
fi
while [ $1 != -- ]
do
        case $1 in
        -a)     # set up the -a flag
                AFLG=1
                AARG=$2
                shift;;
        -b)     # set up the -b flag
                BFLG=1;;
        -c)     # set up the -c flag
                CFLG=1;;
        esac
        shift  # next flag
done
shift# skip double dash
# now do the work
.
.
.

The following are all equivalent arguments to the script:

-a ARG -b -c -- A B C
-a ARG -bc -- A B C
-aARG -b -c -- A B C
-b -c -a ARG -- A B C

SEE ALSO

Commands:  sh(1)

Functions:  getopt(3)