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     getopts - libbash library for command line parameters parsing


     $retval getopt_long 〈Instructions〉 〈Parameters〉


     This  is  a  documentation  for  libbash getopts library, that implements
     getopt_long function for bash(1).   For  documentation  of  bash  getopts
     function, please see getopts(1) ( getopts(1posix) on some systems).

     Here is a table for reference:
     getopts(1)        (or 1posix on some systems) implemented by bash
     getopts(3)        implemented by libbash.
     getopt(1)         implemented by getopt utils (part of util-linux)
     getopt_long(1)    implemented  by  libbash  and  installed  to  section 1
                       instead of 3 to prevent collision with C man pages.
     getopt(3)         implemented by GNU C library.
     getopt_long(3)    implemented by GNU C library.
     I have also  seen  separate  getopt  utility  which  part  of  util-linux

     The  getopt_long  function  parses  the  command line arguments.  It uses
     Instructions as the rules for parsing the Parameters.

   The Instructions
     A string that specifies rules for parameters parsing.  The instructions
     string is built of a group of independent instructions, separated by a
     white space.  Each instruction must have the following structure:


     This structure contains three parts:

            This is the parameter single-letter sign. For example -h.

            This is the parameter’s corresponding multi-letter sign. For
            example --help.

            This is the name of the variable that will contain the parameter
            value. For example: HELP.

            The Variable name can represent one of two variables types:

            Flag variable (not followed by ‘:’)
                 In this case, it will hold the value 1 if ‘on’ (i.e. was
                 specified on command line) and will not be defined if ‘off’.

            Value variable (followed by ‘:’)
                 In this case, the value it will hold is the string that was
                 given as the next parameter in the Parameters string
                 (Separated by white-space or ‘=’ ). If input contains more
                 then one instance of the considered command line option, an
                 array of the given parameters will be set as the value of the

   The Parameters
     The Parameters are simply the parameters you wish to parse.


     This function returns a string that contains a set of variables
     definitions.  In order to define the variables, this string should be
     given as a parameter to eval function. This value is returned in the
     variable $retval.


     Parse command line parameters looking for the flags -h | --help and -v |
     --version and for the value -p | --path :

           getopt_long ’-h|--help->HELP
                         -p|--path->PATH:’ $*
           eval $retval

     In this example, for the parameters --help --path=/usr/ the variables
     that will be created are:


     for the parameters --help --path=/usr --path=/bin the variables that will
     be created are:

           PATH=(/usr /bin)


     Values  must  not  contain  the string ‘__getopts__’. This string will be
     parsed as a single white-space.

     A value should not start with an already defined  multi-letter  sign.  If
     such  a  value  exists, it will be treated as the equivalent singe-letter
     sign. This bug only accures when using a single-letter sign, or a  multi-
     letter sign that are not followed by a ‘=’.

     For example: If we have a script named ‘foo’, and we parse the parameters
     ‘-d|--dir:’ and ‘-f|--file:’, then

           foo -d --file

           foo --dir --file
     will not work

           foo --dir=--file
     will work.


     Hai Zaar 〈〉
     Gil Ran 〈


     ldbash(1), getopt_long(1), getopts(1), getopt(1), libbash(1), getopt(3),