diff --git a/lib/libwebsockets.c b/lib/libwebsockets.c
index d3c91545..86625bed 100644
--- a/lib/libwebsockets.c
+++ b/lib/libwebsockets.c
@@ -922,18 +922,30 @@ lws_ensure_user_space(struct lws *wsi)
 
 LWS_VISIBLE void lwsl_emit_stderr(int level, const char *line)
 {
+	time_t o_now = time(NULL);
+	struct tm o_now_time;
 	unsigned long long now;
 	char buf[300];
-	int n;
+	int n, ok = localtime_r(&o_now, &o_now_time) != NULL;
 
 	buf[0] = '\0';
 	for (n = 0; n < LLL_COUNT; n++) {
 		if (level != (1 << n))
 			continue;
 		now = time_in_microseconds() / 100;
-		sprintf(buf, "[%llu:%04d] %s: ",
-			(unsigned long long) now / 10000,
-			(int)(now % 10000), log_level_names[n]);
+		if (ok)
+			sprintf(buf, "[%04d/%02d/%02d %02d:%02d:%02d:%04d] %s: ",
+				o_now_time.tm_year + 1900,
+				o_now_time.tm_mon,
+				o_now_time.tm_mday,
+				o_now_time.tm_hour,
+				o_now_time.tm_min,
+				o_now_time.tm_sec,
+				(int)(now % 10000), log_level_names[n]);
+		else
+			sprintf(buf, "[%llu:%04d] %s: ",
+					(unsigned long long) now / 10000,
+					(int)(now % 10000), log_level_names[n]);
 		break;
 	}