Function tryCreateLockFile

token/token.go:181–201

tryCreateLockFile atomically creates the lock file using O_CREATE|O_EXCL and writes the current process's PID and start time into it as JSON. The file is created with 0600 permissions (owner read/write only).

(path string)

// and writes the current process's PID and start time into it as JSON.
// The file is created with 0600 permissions (owner read/write only).
func tryCreateLockFile(path string) (retErr error) {
	f, err := os.OpenFile(path, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0600) // nolint: gosec
	if err != nil {
		return err
	}
	defer func() {
		if retErr != nil {
			_ = f.Close()
			_ = os.Remove(path)
			return
		}
		retErr = f.Close()
	}()

	content, err := newSelfLockContent()
	if err != nil {
		return err
	}

	return json.NewEncoder(f).Encode(content)
}

// newSelfLockContent returns a lockContent describing the current process.
func newSelfLockContent() (lockContent, error) {