doc: clarify interaction of ioutil.WriteFile with umask

Note that ioutil.WriteFile's perm argument is the value before the
umask is applied.

Fixes #35835

Change-Id: I61cd9c88bced3be52b616d86e060cd3fd912ab1f

Change-Id: I61cd9c88bced3be52b616d86e060cd3fd912ab1f
GitHub-Last-Rev: 0069abb7c5
GitHub-Pull-Request: golang/go#35836
Reviewed-on: https://go-review.googlesource.com/c/go/+/208838
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This commit is contained in:
Mostyn Bramley-Moore 2019-11-27 00:10:47 +00:00 committed by Ian Lance Taylor
parent 0f25102858
commit 95c9a656ae

View File

@ -74,8 +74,8 @@ func ReadFile(filename string) ([]byte, error) {
}
// WriteFile writes data to a file named by filename.
// If the file does not exist, WriteFile creates it with permissions perm;
// otherwise WriteFile truncates it before writing.
// If the file does not exist, WriteFile creates it with permissions perm
// (before umask); otherwise WriteFile truncates it before writing.
func WriteFile(filename string, data []byte, perm os.FileMode) error {
f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
if err != nil {