diff --git a/btbridged.c b/btbridged.c
index c6a7496..d51b078 100644
--- a/btbridged.c
+++ b/btbridged.c
@@ -95,7 +95,7 @@
 
 	clock_gettime(CLOCK_REALTIME, &time);
 
-	fprintf(s, "[%s %ld.%.9ld] ", PREFIX, time.tv_sec, time.tv_nsec);
+	fprintf(s, "[%s %lld.%.9ld] ", PREFIX, (unsigned long long)time.tv_sec, time.tv_nsec);
 
 	vfprintf(s, fmt, args);
 }