--- a/parse.c
+++ b/parse.c
@@ -1,3 +1,4 @@
+#include <inttypes.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
@@ -39,7 +40,7 @@ static void print_radiotap_namespace(str
 {
 	switch (iter->this_arg_index) {
 	case IEEE80211_RADIOTAP_TSFT:
-		printf("\tTSFT: %llu\n", le64toh(*(unsigned long long *)iter->this_arg));
+		printf("\tTSFT: %" PRIu64 "\n", le64toh(*(uint64_t *)iter->this_arg));
 		break;
 	case IEEE80211_RADIOTAP_FLAGS:
 		printf("\tflags: %02x\n", *iter->this_arg);