Bug not in any released Tor.
@@ -289,6 +289,9 @@ static int keypin_journal_fd = -1;
int
keypin_open_journal(const char *fname)
{
+#ifndef O_SYNC
+#define O_SYNC 0
+#endif
int fd = tor_open_cloexec(fname, O_WRONLY|O_CREAT|O_BINARY|O_SYNC, 0600);
if (fd < 0)
goto err;