From 12c63abd9d8cdfe06a4afa66ab6a6b84884b660f Mon Sep 17 00:00:00 2001
From: Martin Tournoij <martin@arp242.net>
Date: Fri, 29 Jul 2022 22:26:44 +0200
Subject: [PATCH] macos: retry if open() returns EINTR

Retry the unix.Open() if the error returned is EINTR; looking around the
web it seems many systems handle it like this. This is also what
os.Open() does:
https://github.com/golang/go/commit/50d0ee0c98ea21f818d2daa9bc21ef51861a2ef9

Fixes #354
---
 kqueue.go | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/kqueue.go b/kqueue.go
index 5247f7dc..09cefd57 100644
--- a/kqueue.go
+++ b/kqueue.go
@@ -237,8 +237,17 @@ func (w *Watcher) addWatch(name string, flags uint32) (string, error) {
 			}
 		}
 
-		watchfd, err = unix.Open(name, openMode, 0)
-		if watchfd == -1 {
+		// Retry on EINTR; open() can return EINTR in practice on macOS.
+		// See #354, and go issues 11180 and 39237.
+		for {
+			watchfd, err = unix.Open(name, openMode, 0)
+			if err == nil {
+				break
+			}
+			if errors.Is(err, unix.EINTR) {
+				continue
+			}
+
 			return "", err
 		}