soniakeys / exit

Exit a program while both running deferred functions and returning an exit code

Exit

Exit provides a way to exit from a program while both running deferred functions and returning a non-zero exit code.

Deferred functions are great for resource clean up. os.Exit exits a program immediately with an exit code, but doesn't run your deferred functions. This package provides a simple way to do both, exit a program immediately with an exit code, but also run the deferred functions on the way out.

Of course it's just an application of panic and recover but the package saves you writing that little bit of code for every command line program where you want this capability.

Example

package main

import (
   "fmt"

   "github.com/soniakeys/exit"
)

func main() {
  defer exit.Handler() // do this once at the beginning of the program
  f()
  fmt.Println("f returned")
}

func f() {
   defer fmt.Println("f cleanup")
   fmt.Println("f attempt")
   if !false {
      exit.Log("Fatal error in f") // use exit.Log anywhere
   }
   fmt.Println("f completed")
}

$ go build example.go
$ ./example 2>log
f attempt
f cleanup

$ echo $?
1

$ cat log
2014/10/02 20:03:59 Fatal error in f

See also

Similar package at https://github.com/youtube/vitess/tree/master/go/exit