lib/binary-io.c

   1 /* Binary mode I/O.
   2    Copyright 2017-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file 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 Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #include <config.h>
  18
  19 #define BINARY_IO_INLINE _GL_EXTERN_INLINE
  20 #include "binary-io.h"
  21
  22 #if defined __DJGPP__ || defined __EMX__
  23 # include <unistd.h>
  24
  25 int
  26 set_binary_mode (int fd, int mode)
  27 {
  28   if (isatty (fd))
  29     /* If FD refers to a console (not a pipe, not a regular file),
  30        O_TEXT is the only reasonable mode, both on input and on output.
  31        Silently ignore the request.  If we were to return -1 here,
  32        all programs that use xset_binary_mode would fail when run
  33        with console input or console output.  */
  34     return O_TEXT;
  35   else
  36     return __gl_setmode (fd, mode);
  37 }
  38
  39 #endif