diff --git a/open_mode_bsd.go b/open_mode_bsd.go
index 7d8de145..2306c462 100644
--- a/open_mode_bsd.go
+++ b/open_mode_bsd.go
@@ -8,4 +8,4 @@ package fsnotify
 
 import "golang.org/x/sys/unix"
 
-const openMode = unix.O_NONBLOCK | unix.O_RDONLY
+const openMode = unix.O_NONBLOCK | unix.O_RDONLY | unix.O_CLOEXEC
diff --git a/open_mode_darwin.go b/open_mode_darwin.go
index 9139e171..870c4d6d 100644
--- a/open_mode_darwin.go
+++ b/open_mode_darwin.go
@@ -9,4 +9,4 @@ package fsnotify
 import "golang.org/x/sys/unix"
 
 // note: this constant is not defined on BSD
-const openMode = unix.O_EVTONLY
+const openMode = unix.O_EVTONLY | unix.O_CLOEXEC