## exec(cmd, arg, opts) ⇒ Promise.<{stdout: string, stderr: stderr}> Promisified child_process.exec **Kind**: global function | Param | Type | Description | | --- | --- | --- | | cmd | | | | arg | | | | opts | | See child_process.exec node docs | | opts.stdout | stream.Writable | If defined, child process stdout will be piped to it. | | opts.stderr | stream.Writable | If defined, child process stderr will be piped to it. |