1  /* Binary mode I/O.
       2     Copyright 2017-2023 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