errno.h

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   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
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 /*
  20  *      ISO C Standard: 4.1.3 Errors    <errno.h>
  21  */
  22
  23 #ifndef _ERRNO_H
  24
  25 /* The includer defined __need_Emath if he wants only the definitions
  26    of EDOM and ERANGE, and not everything else.  */
  27 #ifndef __need_Emath
  28 #define _ERRNO_H        1
  29 #include <features.h>
  30 #endif
  31
  32 __BEGIN_DECLS
  33
  34 /* Get the error number constants from the system-specific file.
  35    This file will test __need_Emath and _ERRNO_H.  */
  36 #include <errnos.h>
  37 #undef  __need_Emath
  38
  39 #ifdef  _ERRNO_H
  40
  41 /* Declare the `errno' variable, unless it's defined as a macro by
  42    errnos.h.  This is the case in GNU, where it is a per-thread variable.
  43    This redeclaration using the macro still works, but it will be a
  44    function declaration without a prototype and may trigger a
  45    -Wstrict-prototypes warning.  */
  46 #ifndef errno
  47 extern int errno;
  48 #endif
  49
  50 #ifdef __USE_GNU
  51
  52 /* The full and simple forms of the name with which the program was
  53    invoked.  These variables are set up automatically at startup based on
  54    the value of ARGV[0] (this works only if you use GNU ld).  */
  55 extern char *program_invocation_name, *program_invocation_short_name;
  56 #endif /* __USE_GNU */
  57 #endif /* _ERRNO_H */
  58
  59 __END_DECLS
  60
  61 #endif /* _ERRNO_H */
  62
  63 /* The Hurd <errnos.h> defines `error_t' as an enumerated type so that
  64    printing `error_t' values in the debugger shows the names.  We
  65    might need this definition sometimes even if this file was included
  66    before.  */
  67 #if defined __USE_GNU || defined __need_error_t
  68 # ifndef __error_t_defined
  69 typedef int error_t;
  70 #  define __error_t_defined     1
  71 # endif
  72 # undef __need_error_t
  73 #endif