# HG changeset patch
# User David A. Holland
# Date 1373391807 14400
# Node ID 0816803b22d1474f0c7542efc2211b2c8afbdee2
# Parent  59680a727e9da1343a11f7dfca2c79d800fb3dbf
Improve usage reporting.

Since imake is a principal application for tradcpp and imake carefully
hides what it's doing when you run it, when rejecting an invalid
option be sure to report *what* that option is.

diff -r 59680a727e9d -r 0816803b22d1 CHANGES
--- a/CHANGES	Tue Jul 09 13:38:43 2013 -0400
+++ b/CHANGES	Tue Jul 09 13:43:27 2013 -0400
@@ -1,6 +1,9 @@
 pending
    - Don't leak memory and assert if a bad command-line option comes
      after a -D or a -include foo.
+   - Since imake is a principal application for tradcpp and imake carefully
+     hides what it's doing when you run it, when rejecting an invalid option
+     be sure to report *what* that option is.
 
 release 0.3 (20130616)
    - Don't eval the control expression of the first #if of a block when
diff -r 59680a727e9d -r 0816803b22d1 main.c
--- a/main.c	Tue Jul 09 13:38:43 2013 -0400
+++ b/main.c	Tue Jul 09 13:43:27 2013 -0400
@@ -909,13 +909,20 @@
 
 DEAD static
 void
-usage(const char *argv0)
+usage(const char *argv0, const char *fmt, ...)
 {
 	const char *progname;
+	va_list ap;
 
 	progname = strrchr(argv0, '/');
 	progname = progname == NULL ? argv0 : progname + 1;
 
+	fprintf(stderr, "%s: ", progname);
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fprintf(stderr, "\n");
+
 	fprintf(stderr, "Usage: %s [options] [infile [outfile]]\n", progname);
 	fprintf(stderr, "Common options:\n");
 	fprintf(stderr, "   -C               Retain comments\n");
@@ -1023,7 +1030,7 @@
 			i++;
 			continue;
 		}
-		usage(argv[0]);
+		usage(argv[0], "Invalid option %s", argv[i]);
 	}
 	if (i < argc) {
 		inputfile = argv[i++];
@@ -1032,7 +1039,7 @@
 		outputfile = argv[i++];
 	}
 	if (i < argc) {
-		usage(argv[0]);
+		usage(argv[0], "Extra non-option argument %s", argv[i]);
 	}
 
 	mode.output_file = outputfile;