Subject: [RFC][PATCH] Print the usage string on stdout instead of stderr.

From: Giuseppe Scrivano <[email-masked]>
Date: Mon, 17 May 2010 11:48:38 +0200

Hello,

I have noticed that the -h flag uses stderr to print the usage string,
is there any reason for it?

The small patch I have attached changes -h to print on stdout.

Thanks,
Giuseppe

>>From 4a5c4e4470dae11e22ff233b34a10b6a912fcd3e Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <[email-masked]>
Date: Mon, 17 May 2010 11:31:09 +0200
Subject: [PATCH] Print the usage string on stdout instead of stderr.

Signed-off-by: Giuseppe Scrivano <[email-masked]>
---
 parse-options.c |   36 +++++++++++++++++-------------------
 1 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/parse-options.c b/parse-options.c
index 8546d85..9adaf44 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -479,7 +479,7 @@ static int usage_argh(const struct option *opts)
 			s = literal ? "[%s]" : "[<%s>]";
 	else
 		s = literal ? " %s" : " <%s>";
-	return fprintf(stderr, s, opts->argh ? opts->argh : "...");
+	return printf(s, opts->argh ? opts->argh : "...");
 }
 
 #define USAGE_OPTS_WIDTH 24
@@ -491,47 +491,45 @@ static int usage_with_options_internal(const char * const *usagestr,
 	if (!usagestr)
 		return PARSE_OPT_HELP;
 
-	fprintf(stderr, "usage: %s\n", *usagestr++);
+	printf("usage: %s\n", *usagestr++);
 	while (*usagestr && **usagestr)
-		fprintf(stderr, "   or: %s\n", *usagestr++);
+		printf("   or: %s\n", *usagestr++);
 	while (*usagestr) {
-		fprintf(stderr, "%s%s\n",
-				**usagestr ? "    " : "",
-				*usagestr);
+		printf("%s%s\n",**usagestr ? "    " : "", *usagestr);
 		usagestr++;
 	}
 
 	if (opts->type != OPTION_GROUP)
-		fputc('\n', stderr);
+		fputc('\n', stdout);
 
 	for (; opts->type != OPTION_END; opts++) {
 		size_t pos;
 		int pad;
 
 		if (opts->type == OPTION_GROUP) {
-			fputc('\n', stderr);
+			fputc('\n', stdout);
 			if (*opts->help)
-				fprintf(stderr, "%s\n", opts->help);
+				printf("%s\n", opts->help);
 			continue;
 		}
 		if (!full && (opts->flags & PARSE_OPT_HIDDEN))
 			continue;
 
-		pos = fprintf(stderr, "    ");
+		pos = printf("    ");
 		if (opts->short_name && !(opts->flags & PARSE_OPT_NEGHELP)) {
 			if (opts->flags & PARSE_OPT_NODASH)
-				pos += fprintf(stderr, "%c", opts->short_name);
+				pos += printf("%c", opts->short_name);
 			else
-				pos += fprintf(stderr, "-%c", opts->short_name);
+				pos += printf("-%c", opts->short_name);
 		}
 		if (opts->long_name && opts->short_name)
-			pos += fprintf(stderr, ", ");
+			pos += printf(", ");
 		if (opts->long_name)
-			pos += fprintf(stderr, "--%s%s",
+			pos += printf("--%s%s",
 				(opts->flags & PARSE_OPT_NEGHELP) ?  "no-" : "",
 				opts->long_name);
 		if (opts->type == OPTION_NUMBER)
-			pos += fprintf(stderr, "-NUM");
+			pos += printf("-NUM");
 
 		if (!(opts->flags & PARSE_OPT_NOARG))
 			pos += usage_argh(opts);
@@ -539,12 +537,12 @@ static int usage_with_options_internal(const char * const *usagestr,
 		if (pos <= USAGE_OPTS_WIDTH)
 			pad = USAGE_OPTS_WIDTH - pos;
 		else {
-			fputc('\n', stderr);
+			fputc('\n', stdout);
 			pad = USAGE_OPTS_WIDTH;
 		}
-		fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
+		printf("%*s%s\n", pad + USAGE_GAP, "", opts->help);
 	}
-	fputc('\n', stderr);
+	fputc('\n', stdout);
 
 	return PARSE_OPT_HELP;
 }
@@ -560,7 +558,7 @@ void usage_msg_opt(const char *msg,
 		   const char * const *usagestr,
 		   const struct option *options)
 {
-	fprintf(stderr, "%s\n\n", msg);
+	printf("%s\n\n", msg);
 	usage_with_options(usagestr, options);
 }
 
-- 
1.7.1