Better spawn

Because child_process.exec lacks features and child_process.spawn acts weird, better-spawn was made.

It is a very simple wrapper around child_process.spawn to make opening and closing work consistently in linux and windows.
Used by script-runner

Install

npm install better-spawn

Breaking changes @1

child.closed and child.killed are now promises. The boolean states are now available at child.isClosed and child.isKilled.

Usage

spawn = require('better-spawn')
child = spawn('node', options)

Options

Name | type | default | description ---:| --- | ---| --- cwd | String | process.cwd | current working directory env | Object | process.env | environment variables env.PATH | String | process.env.PATH + ./node_modules/.bin | used to resolve commands stdio | See documentation | ["pipe","inherit","inherit"] | to control output noOut | Boolean | null | sets stdio[1] = "pipe" noErr | Boolean | null | sets stdio[2] = "pipe" windowsVerbatimArguments | Boolean | isWindows | to support windows detach | Boolean | !isWindows | to support killing on unix Promise | Function | global.Promise | supply your own Promise lib

Props

Name | type | description ---:| --- | --- cmd | String | cmd called isKilled | Boolean | is child process killed isClosed | Boolean | is child process closed killed | Promise | fulfilled when child process killed closed | Promise | fulfilled when child process closed close | Function | call to kill child process

Examples

// pipe to shell without losing color
child = spawn('node')
// suppress normal output, but maintain err output
child = spawn('node',{noOut:true})
// set empty env (default in node)
child = spawn('node',{env: {PATH:""}})

Compare to other solutions

• child_process.exec, spawns in shell but output has to be piped - color information will be lost.
• child_process.spawn, doesn't spawn in shell, so it has to be done by hand (differs in linux and windows) Main problem is, sh won't kill its children by child.kill(), see: node#2098
• cross-spawn-async a wrapper for child_process.spawn to support windows quirks like PATHEXT or shebangs not working
• execa a wrapper for cross-spawn-async which adds the shell logic, to behave like child_process.exec, adds promises, modifies PATH

better-spawn doesn't support PATHEXT or shebangs on windows

License

Copyright (c) 2016 Paul Pflugradt Licensed under the MIT license.