1 files changed, 38 insertions, 9 deletions

diff --git a/src/systemcmds/param/param.c b/src/systemcmds/param/param.c
index 65f291f40..580fdc62f 100644
--- a/src/systemcmds/param/param.c
+++ b/src/systemcmds/param/param.c
@@ -72,7 +72,12 @@ param_main(int argc, char *argv[])
 			if (argc >= 3) {
 				do_save(argv[2]);
 			} else {
-				do_save(param_get_default_file());
+				if (param_save_default()) {
+					warnx("Param export failed.");
+					exit(1);
+				} else {
+					exit(0);
+				}
 			}
 		}
 
@@ -133,11 +138,8 @@ param_main(int argc, char *argv[])
 static void
 do_save(const char* param_file_name)
 {
-	/* delete the parameter file in case it exists */
-	unlink(param_file_name);
-
 	/* create the file */
-	int fd = open(param_file_name, O_WRONLY | O_CREAT | O_EXCL);
+	int fd = open(param_file_name, O_WRONLY | O_CREAT);
 
 	if (fd < 0)
 		err(1, "opening '%s' failed", param_file_name);
@@ -146,7 +148,7 @@ do_save(const char* param_file_name)
 	close(fd);
 
 	if (result < 0) {
-		unlink(param_file_name);
+		(void)unlink(param_file_name);
 		errx(1, "error exporting to '%s'", param_file_name);
 	}
 
@@ -203,11 +205,38 @@ do_show_print(void *arg, param_t param)
 	int32_t i;
 	float f;
 	const char *search_string = (const char*)arg;
+	const char *p_name = (const char*)param_name(param);
 
 	/* print nothing if search string is invalid and not matching */
-	if (!(arg == NULL || (!strcmp(search_string, param_name(param))))) {
-		/* param not found */
-		return;
+	if (!(arg == NULL)) {
+
+		/* start search */
+		char *ss = search_string;
+		char *pp = p_name;
+		bool mismatch = false;
+
+		/* XXX this comparison is only ok for trailing wildcards */
+		while (*ss != '\0' && *pp != '\0') {
+
+			if (*ss == *pp) {
+				ss++;
+				pp++;
+			} else if (*ss == '*') {
+				if (*(ss + 1) != '\0') {
+					warnx("* symbol only allowed at end of search string.");
+					exit(1);
+				}
+
+				pp++;
+			} else {
+				/* param not found */
+				return;
+			}
+		}
+
+		/* the search string must have been consumed */
+		if (!(*ss == '\0' || *ss == '*'))
+			return;
 	}
 
 	printf("%c %s: ",