File.Write() creates empty files

[Denis Karimov]

Code:

var Location vfs.Location = initLocation()

func initLocation() vfs.Location {

	if location, err := vfssimple.NewLocation("file:///path/to/public"); err != nil {
		log.Fatal(err.Error())
	} else if ok, err := location.Exists(); err != nil {
		log.Fatal(err.Error())
	} else if !ok {
		log.Fatal("Unexpected error")
	} else {
		return location
	}

	return nil
}

func MakeTestFile() {
	f, err := Location.NewFile("test.txt")

	if err != nil {
		log.Fatal(err.Error())
	}

	if num, err := f.Write([]byte("This is a test text")); err != nil {
		log.Fatal(err.Error())
	} else {
		log.Println("String was writed in file")
	}

	f.Close()
}

Problem:

The function MakeTestFile creates a file without errors, but it is empty.

System information:

• Go version: 1.14.1
• Os/Arch: linux/amd64
• Package version: 1.6.2

[Denis Karimov]

But! The temp folder contains a text file named test.txt.1605546281517101373860380273. I can't understand why this is happening.

[Denis Karimov]

As I understand, the file should be moved from the temp folder to the expected location with f.Close (). But I am getting error:

rename /tmp/test.txt.1605550051063334634276804707 /path/to/public/test.txt: invalid cross-device link

[John Judd]

Sorry, i hadn't noticed this. I'll try to take a look in the next couple of days.

[John Judd]

It seems the issue is that fact that /tmp and /path/to/public/ are mounted on different filesystems. It makes some since that renaming across filesystem boundaries doesn't work. Renaming (os.Rename()) is less expensive than a copy/delete (move) but copye/delete would solve for this.