include/binary-io.h

   1 /* Binary mode I/O.
   2    Copyright (C) 2001-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 #ifndef _BINARY_H
  18 #define _BINARY_H
  19
  20 /* Include this header after <fcntl.h> and <stdio.h>, because
  21    systems that distinguish between text and binary I/O usually
  22    define O_BINARY in <fcntl.h>, and the MSVC7 <stdio.h> doesn't
  23    like to be included after '#define fileno ...'
  24
  25    We don't include <fcntl.h> here because not all systems have
  26    that header.  */
  27
  28 #if !defined O_BINARY && defined _O_BINARY
  29   /* For MSC-compatible compilers.  */
  30 # define O_BINARY _O_BINARY
  31 # define O_TEXT _O_TEXT
  32 #endif
  33 #ifdef __BEOS__
  34   /* BeOS 5 has O_BINARY and O_TEXT, but they have no effect.  */
  35 # undef O_BINARY
  36 # undef O_TEXT
  37 #endif
  38 #if O_BINARY
  39 # if defined __EMX__ || defined __DJGPP__ || defined __CYGWIN__
  40 #  include <io.h> /* declares setmode() */
  41 # else
  42 #  define setmode _setmode
  43 #  undef fileno
  44 #  define fileno _fileno
  45 # endif
  46 # ifdef __DJGPP__
  47 #  include <unistd.h> /* declares isatty() */
  48 #  /* Avoid putting stdin/stdout in binary mode if it is connected to the
  49 #     console, because that would make it impossible for the user to
  50 #     interrupt the program through Ctrl-C or Ctrl-Break.  */
  51 #  define SET_BINARY(fd) (!isatty (fd) ? (setmode (fd, O_BINARY), 0) : 0)
  52 # else
  53 #  define SET_BINARY(fd) setmode (fd, O_BINARY)
  54 # endif
  55 #else
  56   /* On reasonable systems, binary I/O is the default.  */
  57 # undef O_BINARY
  58 # define O_BINARY 0
  59 # define SET_BINARY(fd) /* nothing */
  60 #endif
  61
  62 #endif /* _BINARY_H */