getopt.h

/* Declarations for getopt. Copyright (C) 1989,90,91,92,93,94,96,97,98 Free
   Software Foundation, Inc. This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or modify it 
   under the terms of the GNU Library General Public License as published by
   the Free Software Foundation; either version 2 of the License, or (at your
   option) any later version.

   The GNU C Library is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
   License for more details.

   You should have received a copy of the GNU Library General Public License
   along with the GNU C Library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.  */

#ifndef _GETOPT_H

#ifndef __need_getopt
# define _GETOPT_H 1
#endif

#ifdef  __cplusplus
extern "C" {
#endif

  /* For communication from `getopt' to the caller. When `getopt' finds an
     option that takes an argument, the argument value is returned here. Also,
     when `ordering' is RETURN_IN_ORDER, each non-option ARGV-element is
     returned here.  */

  extern char *optarg;

  /* Index in ARGV of the next element to be scanned. This is used for
     communication to and from the caller and for communication between
     successive calls to `getopt'.

     On entry to `getopt', zero means this is the first call; initialize.

     When `getopt' returns -1, this is the index of the first of the non-option 
     elements that the caller should itself scan.

     Otherwise, `optind' communicates from one call to the next how much of
     ARGV has been scanned so far.  */

  extern int optind;

  /* Callers store zero here to inhibit the error message `getopt' prints for
     unrecognized options.  */

  extern int opterr;

  /* Set to an option character which was unrecognized.  */

  extern int optopt;

#ifndef __need_getopt
  /* Describe the long-named options requested by the application. The
     LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector of
     `struct option' terminated by an element containing a name which is zero.

     The field `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,
     optional_argument (or 2) if the option takes an optional argument.

     If the field `flag' is not NULL, it points to a variable that is set to
     the value given in the field `val' when the option is found, but left
     unchanged if the option is not found.

     To have a long-named option do something other than set an `int' to a
     compiled-in constant, such as set a value from `optarg', set the option's
     `flag' field to zero and its `val' field to a nonzero value (the
     equivalent single-letter option character, if there is one).  For long
     options that have a zero `flag' field, `getopt' returns the contents of
     the `val' field.  */

  struct option {
# if defined __STDC__ && __STDC__
    const char *name;
# else
    char *name;
# endif
    /* has_arg can't be an enum because some compilers complain about type
       mismatches in all the code that assumes it is an int.  */
    int has_arg;
    int *flag;
    int val;
  };

  /* Names for the values of the `has_arg' field of `struct option'.  */

# define no_argument    0
# define required_argument  1
# define optional_argument  2
#endif        /* need getopt */

  /* Get definitions and prototypes for functions to process the arguments in
     ARGV (ARGC of them, minus the program name) for options given in OPTS.

     Return the option character from OPTS just read.  Return -1 when there are 
     no more options.  For unrecognized options, or options missing arguments,
     `optopt' is set to the option letter, and '?' is returned.

     The OPTS string is a list of characters which are recognized option
     letters, optionally followed by colons, specifying that that letter takes
     an argument, to be placed in `optarg'.

     If a letter in OPTS is followed by two colons, its argument is optional.
     This behavior is specific to the GNU `getopt'.

     The argument `--' causes premature termination of argument scanning,
     explicitly telling `getopt' that there are no more options.

     If OPTS begins with `--', then non-option arguments are treated as
     arguments to the option '\0'.  This behavior is specific to the GNU
     `getopt'.  */

#if defined __STDC__ && __STDC__
# ifdef __GNU_LIBRARY__
  /* Many other libraries have conflicting prototypes for getopt, with
     differences in the consts, in stdlib.h.  To avoid compilation errors, only 
     prototype getopt for the GNU C library.  */
  extern int getopt(int __argc, char *const *__argv, const char *__shortopts);
# else        /* not __GNU_LIBRARY__ */
  extern int getopt();
# endif       /* __GNU_LIBRARY__ */

# ifndef __need_getopt
  extern int getopt_long(int __argc, char *const *__argv,
       const char *__shortopts,
       const struct option *__longopts, int *__longind);
  extern int getopt_long_only(int __argc, char *const *__argv,
            const char *__shortopts,
            const struct option *__longopts, int *__longind);

  /* Internal only.  Users should not call this directly.  */
  extern int _getopt_internal(int __argc, char *const *__argv,
            const char *__shortopts,
            const struct option *__longopts, int *__longind,
            int __long_only);
# endif
#else       /* not __STDC__ */
  extern int getopt();
# ifndef __need_getopt
  extern int getopt_long();
  extern int getopt_long_only();

  extern int _getopt_internal();
# endif
#endif        /* __STDC__ */

#ifdef  __cplusplus
}
#endif
/* Make sure we later can get all the definitions and declarations.  */
#undef __need_getopt
#endif        /* getopt.h */

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