Golang : Test file read write permission example
Problem :
You need to test if a file has the correct write or read permission before performing write or read operation. How to do that?
Solution :
Use os.OpenFile()
function and check the error with os.IsPermission() to see if a file has permission denied error.
For example :
To test if a file has write permission : (do not run this program as root or super user)
package main
import (
"fmt"
"os"
)
func main() {
fileName := "file.txt"
file, err := os.OpenFile(fileName, os.O_WRONLY, 0666)
if err != nil {
if os.IsPermission(err) {
fmt.Println("Unable to write to ", fileName)
fmt.Println(err)
os.Exit(1)
}
}
file.Close()
}
To test if a file has read permission : (do not run this program as root or super user)
package main
import (
"fmt"
"os"
)
func main() {
fileName := "file.txt"
file, err = os.OpenFile(fileName, os.O_RDONLY, 0666)
if err != nil {
if os.IsPermission(err) {
fmt.Println("Unable to read from ", fileName)
fmt.Println(err)
os.Exit(1)
}
}
file.Close()
}
References :
https://golang.org/pkg/os/#IsPermission
https://www.socketloop.com/tutorials/golang-check-if-a-file-exist-or-not
See also : Golang : Get file permission
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+10.2k Golang : ISO8601 Duration Parser example
+7.2k Golang : Get YouTube playlist
+9.7k CodeIgniter : Load different view for mobile devices
+33.5k Golang : Proper way to set function argument default value
+5.8k Golang : How to write backslash in string?
+34.8k Golang : Strip slashes from string example
+4.5k Python : Find out the variable type and determine the type with simple test
+7.5k Golang : Regular Expression find string example
+5.2k PHP : Fix Call to undefined function curl_init() error
+13.6k Golang: Pad right or print ending(suffix) zero or spaces in fmt.Printf example
+12.3k Golang : Drop cookie to visitor's browser and http.SetCookie() example
+28.8k Golang : missing Git command