Initial revision

1 files changed, 88 insertions, 0 deletions

diff --git a/src/tty.c b/src/tty.c
new file mode 100644
index 000000000..056c7da8d
--- /dev/null
+++ b/src/tty.c
@@ -0,0 +1,88 @@
+/* tty -- print the path of the terminal connected to standard input
+   Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+/* Displays "not a tty" if stdin is not a terminal.
+   Displays nothing if -s option is given.
+   Exit status 0 if stdin is a tty, 1 if not, 2 if usage error.
+
+ Written by David MacKenzie (djm@ai.mit.edu).  */
+
+#include <stdio.h>
+#include <getopt.h>
+#include <sys/types.h>
+#include "system.h"
+
+void usage ();
+
+/* The name under which this program was run. */
+char *program_name;
+
+/* If nonzero, return an exit status but produce no output. */
+int silent;
+
+struct option longopts[] =
+{
+  {"silent", 0, NULL, 's'},
+  {"quiet", 0, NULL, 's'},
+  {NULL, 0, NULL, 0}
+};
+
+void
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  char *tty;
+  int optc;
+
+  program_name = argv[0];
+  silent = 0;
+
+  while ((optc = getopt_long (argc, argv, "s", longopts, (int *) 0)) != EOF)
+    {
+      switch (optc)
+	{
+	case 's':
+	  silent = 1;
+	  break;
+	default:
+	  usage ();
+	}
+    }
+
+  if (optind != argc)
+    usage ();
+
+  tty = ttyname (0);
+  if (!silent)
+    {
+      if (tty)
+	puts (tty);
+      else
+	puts ("not a tty");
+    }
+
+  exit (tty == NULL);
+}
+
+void
+usage ()
+{
+  fprintf (stderr, "\
+Usage: %s [-s] [--silent] [--quiet]\n", program_name);
+  exit (2);
+}