include unistd.h for getopt
diff --git a/notify.c b/notify.c
index b1761d2..c23e9d8 100644
--- a/notify.c
+++ b/notify.c
@@ -6,6 +6,7 @@
 #include <sys/ioctl.h>
 #include <sys/inotify.h>
 #include <errno.h>
+#include <unistd.h>
 
 int notify_main(int argc, char *argv[])
 {