gm2-libs/GetOpt (The GNU Modula-2 Compiler)

#### 4.1.18 gm2-libs/GetOpt ¶

    DEFINITION MODULE GetOpt ;

    FROM SYSTEM IMPORT ADDRESS ;
    FROM DynamicStrings IMPORT String ;

    CONST
       no_argument = 0 ;
       required_argument = 1 ;
       optional_argument = 2 ;

    TYPE
       LongOptions ;
       PtrToInteger = POINTER TO INTEGER ;

    (*
       GetOpt - call C getopt and fill in the parameters:
                optarg, optind, opterr and optopt.
    *)

    PROCEDURE GetOpt (argc: INTEGER; argv: ADDRESS; optstring: String;
                      VAR optarg: String;
                      VAR optind, opterr, optopt: INTEGER) : CHAR ;

    (*
       InitLongOptions - creates and returns a LongOptions empty array.
    *)

    PROCEDURE InitLongOptions () : LongOptions ;

    (*
       AddLongOption - appends long option {name, has_arg, flag, val} to the
                       array of options and new long options array is
                       returned.
                       The old array, lo, should no longer be used.

       (from man 3 getopt)
           The meanings of the different fields are:

           name   is the name of the long option.

           has_arg
                  is: no_argument (or 0) if the option does not take an
                  argument; required_argument (or  1) if the option
                  requires an argument; or optional_argument (or 2) if
                  the option takes an optional argument.

           flag   specifies how results are returned for a long option.
                  If flag is NULL, then getopt_long() returns val.
                  (For example, the calling program may set val to the
                  equivalent short option character).  Otherwise,
                  getopt_long() returns 0, and flag points to a
                  variable which is set to val if the option is found,
                  but left unchanged if the option is not found.

           val    is the value to return, or to load into the variable
                  pointed to by flag.

           The last element of the array must be filled with zeros.
    *)

    PROCEDURE AddLongOption (lo: LongOptions; index: CARDINAL;
                             name: String; has_arg: INTEGER;
                             VAR flag: INTEGER; val: INTEGER) : LongOptions ;

    (*
       KillLongOptions - returns NIL and also frees up memory
                         associated with, lo.
    *)

    PROCEDURE KillLongOptions (lo: LongOptions) : LongOptions ;

    (*
       GetOptLong - works like GetOpt but will accept long options (using
                    two dashes).  If the program only accepts long options
                    then optstring should be an empty string, not NIL.
    *)

    PROCEDURE GetOptLong (argc: INTEGER; argv: ADDRESS;
                          optstring: String; longopts: LongOptions;
                          VAR longindex: INTEGER) : INTEGER ;

    (*
       GetOptLongOnly - works like GetOptLong except that a single dash
                        can be used for a long option.
    *)

    PROCEDURE GetOptLongOnly (argc: INTEGER; argv: ADDRESS;
                              optstring: String; longopts: LongOptions;
                              VAR longindex: INTEGER) : INTEGER ;

    END GetOpt.