getopts(1)                 (Essential Utilities)                 getopts(1)


   NAME
         getopts, getoptcvt - parse command options

   SYNOPSIS
         getopts optstring name [ arg ... ]

         /usr/lib/getoptcvt [ -b ] file

   DESCRIPTION
         getopts is used by shell procedures to parse positional parameters
         and to check for valid options.  It supports all applicable rules of
         the command syntax standard (see Rules 3-10, intro(1)).  It should be
         used in place of the getopt command.  (See the NOTES section below.)

         optstring must contain the option letters the command using getopts
         will recognize; if a letter is followed by a colon, the option is
         expected to have an argument, or group of arguments, which must be
         separated from it by white space.

         Each time it is invoked, getopts places the next option in the shell
         variable name and the index of the next argument to be processed in
         the shell variable OPTIND.  Whenever the shell or a shell procedure
         is invoked, OPTIND is initialized to 1.

         When an option requires an option-argument, getopts places it in the
         shell variable OPTARG.

         If an illegal option is encountered, ?  will be placed in name.

         When the end of options is encountered, getopts exits with a non-zero
         exit status.  The special option -- may be used to delimit the end of
         the options.

         By default, getopts parses the positional parameters.  If extra
         arguments (arg ...)  are given on the getopts command line, getopts
         parsees them instead.

         /usr/lib/getoptcvt reads the shell script in file, converts it to use
         getopts instead of getopt, and writes the results on the standard
         output.

         -b    Make the converted script portable to earlier releases of the
               UNIX system.  /usr/lib/getoptcvt modifies the shell script in
               file so that when the resulting shell script is executed, it
               determines at run time whether to invoke getopts or getopt.

         So all new commands will adhere to the command syntax standard
         described in intro(1), they should use getopts or getopt to parse
         positional parameters and check for options that are valid for that
         command (see the NOTES section below).



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   getopts(1)                 (Essential Utilities)                 getopts(1)


   EXAMPLE
         The following fragment of a shell program 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 option-argument:

               while getopts abo: c
               do
                    case $c in
                    a | b)    FLAG=$c;;
                    o)        OARG=$OPTARG;;
                    \?)       echo $USAGE
                              exit 2;;
                    esac
               done
               shift `expr $OPTIND - 1`

         This code accepts any of the following as equivalent:

               cmd -a -b -o "xxx z yy" file
               cmd -a -b -o "xxx z yy" -- file
               cmd -ab -o xxx,z,yy file
               cmd -ab -o "xxx z yy" file
               cmd -o xxx,z,yy -b -a file

   SEE ALSO
         intro(1), sh(1).
         getopt(3C) in the Programmer's Reference Manual.

   NOTES
         Although the following command syntax rule [see intro(1)] relaxations
         are permitted under the current implementation, they should not be
         used because they may not be supported in future releases of the
         system.  As in the EXAMPLE section above, a and b are options, and
         the option o requires an option-argument.  The following example
         violates Rule 5:  options with option-arguments must not be grouped
         with other options:

               cmd -aboxxx file

         The following example violates Rule 6: there must be white space
         after an option that takes an option-argument:

               cmd -ab -oxxx file

         Changing the value of the shell variable OPTIND or parsing different
         sets of arguments may lead to unexpected results.

   DIAGNOSTICS
         getopts prints an error message on the standard error when it
         encounters an option letter not included in optstring.



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