getopt.h 3.7 KB

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  1. /* Declarations for getopt.
  2. Copyright (C) 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Library General Public License as
  6. published by the Free Software Foundation; either version 2 of the
  7. License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Library General Public License for more details.
  12. You should have received a copy of the GNU Library General Public
  13. License along with the GNU C Library; see the file COPYING.LIB. If
  14. not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  15. Cambridge, MA 02139, USA. */
  16. #ifndef _GETOPT_H
  17. #define _GETOPT_H 1
  18. #include <features.h>
  19. #ifdef __cplusplus
  20. extern "C" {
  21. #endif
  22. /* For communication from `getopt' to the caller.
  23. When `getopt' finds an option that takes an argument,
  24. the argument value is returned here.
  25. Also, when `ordering' is RETURN_IN_ORDER,
  26. each non-option ARGV-element is returned here. */
  27. extern char *optarg;
  28. /* Index in ARGV of the next element to be scanned.
  29. This is used for communication to and from the caller
  30. and for communication between successive calls to `getopt'.
  31. On entry to `getopt', zero means this is the first call; initialize.
  32. When `getopt' returns EOF, this is the index of the first of the
  33. non-option elements that the caller should itself scan.
  34. Otherwise, `optind' communicates from one call to the next
  35. how much of ARGV has been scanned so far. */
  36. extern int optind;
  37. /* Callers store zero here to inhibit the error message `getopt' prints
  38. for unrecognized options. */
  39. extern int opterr;
  40. /* Set to an option character which was unrecognized. */
  41. extern int optopt;
  42. /* Describe the long-named options requested by the application.
  43. The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  44. of `struct option' terminated by an element containing a name which is
  45. zero.
  46. The field `has_arg' is:
  47. no_argument (or 0) if the option does not take an argument,
  48. required_argument (or 1) if the option requires an argument,
  49. optional_argument (or 2) if the option takes an optional argument.
  50. If the field `flag' is not NULL, it points to a variable that is set
  51. to the value given in the field `val' when the option is found, but
  52. left unchanged if the option is not found.
  53. To have a long-named option do something other than set an `int' to
  54. a compiled-in constant, such as set a value from `optarg', set the
  55. option's `flag' field to zero and its `val' field to a nonzero
  56. value (the equivalent single-letter option character, if there is
  57. one). For long options that have a zero `flag' field, `getopt'
  58. returns the contents of the `val' field. */
  59. struct option
  60. {
  61. const char *name;
  62. /* has_arg can't be an enum because some compilers complain about
  63. type mismatches in all the code that assumes it is an int. */
  64. int has_arg;
  65. int *flag;
  66. int val;
  67. };
  68. /* Names for the values of the `has_arg' field of `struct option'. */
  69. #define no_argument 0
  70. #define required_argument 1
  71. #define optional_argument 2
  72. extern int getopt __P((int argc, char *const *argv, const char *shortopts));
  73. extern int getopt_long __P((int argc, char *const *argv, const char *shortopts,
  74. const struct option *longopts, int *longind));
  75. extern int getopt_long_only __P((int argc, char *const *argv,
  76. const char *shortopts,
  77. const struct option *longopts, int *longind));
  78. #ifdef __cplusplus
  79. }
  80. #endif
  81. #endif /* _GETOPT_H */