go-coreutils/env/env.go

package main

import (
	"os"
	"os/exec"

	"gopkg.in/alecthomas/kingpin.v2"
	common "source.heropunch.io/tomo/go-coreutils"
)

func main() {
	app := kingpin.New("env", "modify the environment, then print it or run a command")
	ignoreEnv := kingpin.Flag(
		"ignore-environment",
		"Completely ignore the existing environment and execute cmd only with each (var, value) tuple specified.",
	).Short('i').Bool()
	unset := kingpin.Flag("unset", "Unset var in the environment.").PlaceHolder("var").Short('u').Strings()

	cmd := kingpin.Arg("cmd", "").String()
	args := kingpin.Arg("args", "").Strings()

	kingpin.Parse()

	for _, key := range *unset {
		os.Unsetenv(key)
	}

	if *ignoreEnv {
		os.Clearenv()
	}

	if *cmd == "" {
		common.PrintEnv()
		os.Exit(0)
	}
	command := exec.Command(*cmd, *args...)
	err := command.Run()
	app.FatalIfError(err, "error running command:")
}