sysdeps/unix/bsd/tcgetpgrp.c

   1 /* Copyright (C) 1991 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
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <sys/ioctl.h>
  21 #include <errno.h>
  22 #include <unistd.h>
  23 #include <sys/types.h>
  24
  25 /* Return the foreground process group ID of FD.  */
  26 pid_t
  27 DEFUN(tcgetpgrp, (fd), int fd)
  28 {
  29   int pgrp;
  30   if (__ioctl(fd, TIOCGPGRP, &pgrp) < 0)
  31     return (pid_t) -1;
  32   return (pid_t) pgrp;
  33 }