LXR toybox/toys/posix/tty.c

   1/* tty.c - Show stdin's terminal name
   2 *
   3 * Copyright 2011 Rob Landley <rob@landley.net>
   4 *
   5 * See http://opengroup.org/onlinepubs/9699919799/utilities/tty.html
   6
   7USE_TTY(NEWTOY(tty, "s", TOYFLAG_USR|TOYFLAG_BIN))
   8
   9config TTY
  10  bool "tty"
  11  default y
  12  help
  13    usage: tty [-s]
  14
  15    Show filename of terminal connected to stdin. If none print "not a tty"
  16    and exit with nonzero status.
  17
  18    -s  Silent, exit code only
  19*/
  20
  21#include "toys.h"
  22
  23void tty_main(void)
  24{
  25  char *tty = ttyname(0);
  26
  27  toys.exitval = !tty;
  28  if (!toys.optflags) puts(tty ? : "not a tty");
  29}
  30