OSF

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. 

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

NOTES

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

set argv=‘getopt flag_string $∗‘

RELATED INFORMATION

Commands:  sh(1). 

Functions: getopt(3).