blah, forgot to save last time to fix whitespacing

[oweals/busybox.git] / coreutils / tty.c

diff --git a/coreutils/tty.c b/coreutils/tty.c
index 83abaffb59bba55546babe861a22d23079aecf9c..cd2c784fda39a9dc21957214291a1d736eb8dea7 100644 (file)
--- a/coreutils/tty.c
+++ b/coreutils/tty.c
@@ -1,7 +1,8 @@
+/* vi: set sw=4 ts=4: */
 /*
- * Mini tty implementation for busybox
+ * tty implementation for busybox
  *
- * Copyright (C) 2000  Edward Betts <edward@debian.org>.
+ * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
  *
  * 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
@@ -19,24 +20,39 @@
  *
  */
 
-#include "internal.h"
+/* BB_AUDIT SUSv3 compliant */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/tty.html */
+
 #include <stdio.h>
-#include <sys/types.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "busybox.h"
+
+extern int tty_main(int argc, char **argv)
+{
+       const char *s;
+       int silent;             /* Note: No longer relevant in SUSv3. */
+       int retval;
+
+       bb_default_error_retval = 2;    /* SUSv3 requires > 1 for error. */
 
-static const char tty_usage[] = "tty\n\n"
-"Print the file name of the terminal connected to standard input.\n"
-"\t-s\tprint nothing, only return an exit status\n";
+       silent = bb_getopt_ulflags(argc, argv, "s");
 
-extern int tty_main(int argc, char **argv) {
-       char *tty;
+       /* gnu tty outputs a warning that it is ignoring all args. */
+       bb_warn_ignoring_args(argc - optind);
 
-       if (argc > 1) {
-               if (argv[1][0] != '-' || argv[1][1] != 's') usage (tty_usage);
+       retval = 0;
+
+       if ((s = ttyname(0)) == NULL) {
+       /* According to SUSv3, ttyname can on fail with EBADF or ENOTTY.
+        * We know the file descriptor is good, so failure means not a tty. */
+               s = "not a tty";
+               retval = 1;
        }
-       else {
-               tty = ttyname (0);
-               if (tty) puts (tty);
-               else puts ("not a tty");
+
+       if (!silent) {
+               puts(s);
        }
-       exit (isatty (0) ? TRUE : FALSE);
+
+       bb_fflush_stdout_and_exit(retval);
 }