diff options
Diffstat (limited to 'src/tty.c')
| -rw-r--r-- | src/tty.c | 35 |
1 files changed, 32 insertions, 3 deletions
@@ -17,14 +17,19 @@ /* 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. + Exit status 0 if stdin is a tty, 1 if not, 2 if usage error, + 3 if write error. - Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ + Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ #include <stdio.h> #include <getopt.h> #include <sys/types.h> + #include "system.h" +#include "version.h" + +void error (); static void usage (); @@ -34,10 +39,18 @@ char *program_name; /* If nonzero, return an exit status but produce no output. */ static int silent; +/* If non-zero, display usage information and exit. */ +static int show_help; + +/* If non-zero, print the version on standard output and exit. */ +static int show_version; + static struct option const longopts[] = { + {"help", no_argument, &show_help, 1}, {"silent", no_argument, NULL, 's'}, {"quiet", no_argument, NULL, 's'}, + {"version", no_argument, &show_version, 1}, {NULL, 0, NULL, 0} }; @@ -56,14 +69,27 @@ main (argc, argv) { switch (optc) { + case 0: + break; + case 's': silent = 1; break; + default: usage (); } } + if (show_version) + { + printf ("%s\n", version_string); + exit (0); + } + + if (show_help) + usage (); + if (optind != argc) usage (); @@ -74,9 +100,12 @@ main (argc, argv) puts (tty); else puts ("not a tty"); + + if (ferror (stdout) || fclose (stdout) == EOF) + error (3, errno, "standard output"); } - exit (tty == NULL); + exit (isatty (0) ? 0 : 1); } static void |