unix: avoid setting O_NONBLOCK needlessly by checking flags beforehand

Change-Id: I227118221df469a677f3ff140ca7b94acb7f9571 Reviewed-on: https://go-review.googlesource.com/c/sys/+/517576 TryBot-Result: Gopher Robot <[email protected]> Reviewed-by: Michael Knyszek <[email protected]> Run-TryBot: Andy Pan <[email protected]> Reviewed-by: Ian Lance Taylor <[email protected]> Reviewed-by: Tobias Klauser <[email protected]> Run-TryBot: Ian Lance Taylor <[email protected]> Auto-Submit: Ian Lance Taylor <[email protected]>
golang · Aug 10, 2023 · 552c4e8 · 552c4e8
1 parent ee57887
commit 552c4e8
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/unix/syscall_unix.go b/unix/syscall_unix.go
@@ -549,6 +549,9 @@ func SetNonblock(fd int, nonblocking bool) (err error) {
 	if err != nil {
 		return err
 	}
+	if (flag&O_NONBLOCK != 0) == nonblocking {
+		return nil
+	}
 	if nonblocking {
 		flag |= O_NONBLOCK
 	} else {