getopt.h

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/*
 * (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
 *               Alexander Warg <warg@os.inf.tu-dresden.de>
 *     economic rights: Technische Universität Dresden (Germany)
 * License: see LICENSE.spdx (in this directory or the directories above)
 */
#ifndef _GETOPT_H
#define _GETOPT_H
 
#ifndef NULL
#define NULL 0
#endif
 
#include <l4/sys/compiler.h>
 
__BEGIN_DECLS
 
/* 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;
 
/* 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
{
  const char *name;
  /* 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
 
L4_CV int getopt (int argc, char *const *argv, const char *shortopts);
 
L4_CV int getopt_long (int argc, char *const *argv, const char *shortopts,
           const struct option *longopts, int *longind);
L4_CV int getopt_long_only (int argc, char *const *argv,
          const char *shortopts,
                const struct option *longopts, int *longind);
 
L4_CV int _getopt_internal (int argc, char *const *argv,
          const char *shortopts,
                const struct option *longopts, int *longind,
          int long_only);
 
__END_DECLS
 
#endif /* _GETOPT_H */