Function evalShellCommand

kernel.go:773–815

execute shell command. line must start with '$'

(ir *interp.Interp, outerr OutErr, line string)

// execute shell command. line must start with '$'
func evalShellCommand(ir *interp.Interp, outerr OutErr, line string) {
	args := strings.Fields(line[1:])
	if len(args) <= 0 {
		return
	}

	var writersWG sync.WaitGroup
	writersWG.Add(2)

	cmd := exec.Command(args[0], args[1:]...)

	stdout, err := cmd.StdoutPipe()
	if err != nil {
		panic(fmt.Errorf("Command.StdoutPipe() failed: %v", err))
	}

	stderr, err := cmd.StderrPipe()
	if err != nil {
		panic(fmt.Errorf("Command.StderrPipe() failed: %v", err))
	}

	go func() {
		defer writersWG.Done()
		io.Copy(outerr.out, stdout)
	}()

	go func() {
		defer writersWG.Done()
		io.Copy(outerr.err, stderr)
	}()

	err = cmd.Start()
	if err != nil {
		panic(fmt.Errorf("error starting command '%s': %v", line[1:], err))
	}

	err = cmd.Wait()
	if err != nil {
		panic(fmt.Errorf("error waiting for command '%s': %v", line[1:], err))
	}

	writersWG.Wait()
}