/
ioutil.go
39 lines (35 loc) · 851 Bytes
/
ioutil.go
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// Copyright 2012, Google Inc. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ioutil2
import (
"io"
"io/ioutil"
"os"
"path"
)
// Write file to temp and atomically move when everything else succeeds.
func WriteFileAtomic(filename string, data []byte, perm os.FileMode) error {
dir, name := path.Dir(filename), path.Base(filename)
f, err := ioutil.TempFile(dir, name)
if err != nil {
return err
}
n, err := f.Write(data)
f.Close()
if err == nil && n < len(data) {
err = io.ErrShortWrite
} else {
err = os.Chmod(f.Name(), perm)
}
if err != nil {
os.Remove(f.Name())
return err
}
return os.Rename(f.Name(), filename)
}
// Check file exists or not
func FileExists(name string) bool {
_, err := os.Stat(name)
return !os.IsNotExist(err)
}