Golang : Change file read or write permission example

Problem :

You have a file and you need to change a file read, write or execute permission. How to achieve that?

Solutions :

Example 1:

 // use Exec() function
 cmd := exec.Command("chmod", "666", "file.txt")
 out, err := cmd.Output()

Example 2:

 // use os.Chmod() function.
 err := os.Chmod("file.txt", 0777)
 if err != nil {
 fmt.Println(err)
 }