Add -help option

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/xbiff.c b/xbiff.c
index 6e06b64..ea96fb2 100644
--- a/xbiff.c
+++ b/xbiff.c
@@ -68,7 +68,8 @@ static XtActionsRec xbiff_actions[] = {
     { "quit", quit },
 };
 
-static void Usage (void)
+static void _X_NORETURN _X_COLD
+Usage (int exitval)
 {
     const char *help_message =
 "where options include:\n"
@@ -81,11 +82,12 @@ static void Usage (void)
 "    -fg color                      foreground color\n"
 "    -rv                            reverse video\n"
 "    -shape                         shape the window\n"
+"    -help                          print usage info and exit\n"
 "    -version                       print version info and exit\n";
 
     fprintf (stderr, "usage:  %s [-options ...]\n", ProgramName);
     fprintf (stderr, "%s\n", help_message);
-    exit (1);
+    exit (exitval);
 }
 
 
@@ -102,10 +104,13 @@ main (int argc, char **argv)
     /* Handle args that don't require opening a display */
     for (int n = 1; n < argc; n++) {
 	const char *argn = argv[n];
-	/* accept single or double dash for -version */
+	/* accept single or double dash for -help & -version */
 	if (argn[0] == '-' && argn[1] == '-') {
 	    argn++;
 	}
+	if (strcmp(argn, "-help") == 0) {
+	    Usage(0);
+	}
 	if (strcmp(argn, "-version") == 0) {
 	    puts(PACKAGE_STRING);
 	    exit(0);
@@ -114,7 +119,9 @@ main (int argc, char **argv)
 
     toplevel = XtAppInitialize(&xtcontext, "XBiff", options, XtNumber (options),
 			       &argc, argv, NULL, NULL, 0);
-    if (argc != 1) Usage ();
+    if (argc != 1) {
+	Usage(1);
+    }
 
     /*
      * This is a hack so that f.delete will do something useful in this