diff --git a/pgrep.c b/pgrep.c
index 539a2d84..c9bc36e8 100644
--- a/pgrep.c
+++ b/pgrep.c
@@ -886,7 +886,14 @@ static void parse_opts (int argc, char **argv)
 	}
 
 	if (argc - optind == 1)
+	{
 		opt_pattern = argv[optind];
+		if ((!opt_full) && (strlen(opt_pattern) > 16))
+			xwarnx(_("pattern that contains program name longer than 15 characters will result in zero matches\n"
+					 "Try `%s -f' option for thorough search."),
+					 program_invocation_short_name);
+	}
+
 	else if (argc - optind > 1)
 		xerrx(EXIT_USAGE, _("only one pattern can be provided\n"
 				     "Try `%s --help' for more information."),