[PATCH] checkpatch: Print some info if no filenames are given

[Tiezhu Yang]

After commit 45107ff6d526 ("checkpatch: if no filenames then read stdin"),
if no filenames are given, it will read patch from stdin rather than exit
directly, it is better to print some info about what to do next, otherwise
it is a bit confusing whether the script hangs.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
 scripts/checkpatch.pl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 23697a6..d84d4fb 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -361,6 +361,8 @@ if ($^V && $^V lt $minimum_perl_version) {
 
 #if no filenames are given, push '-' to read patch from stdin
 if ($#ARGV < 0) {
+	print "$P: missing patchfile or -f file\n";
+	print "Use --help if necessary or read patch from stdin\n";
 	push(@ARGV, '-');
 }
 
-- 
2.1.0