Function exec

javascript/selenium-webdriver/io/exec.js:123–160

* Spawns a child process. The returned Command may be used to wait * for the process result or to send signals to the process. * * @param {string} command The executable to spawn. * @param {Options=} opt_options The command options. * @return {!Command} The launched command.

(command, opt_options)

 * @return {!Command} The launched command.
 */
function exec(command, opt_options) {
  const options = opt_options || {}

  let proc = childProcess.spawn(command, options.args || [], {
    env: options.env || process.env,
    stdio: options.stdio || 'ignore',
  })

  // This process should not wait on the spawned child, however, we do
  // want to ensure the child is killed when this process exits.
  proc.unref()
  process.once('exit', onProcessExit)

  const result = new Promise((resolve, reject) => {
    proc.once('exit', (code, signal) => {
      proc = null
      process.removeListener('exit', onProcessExit)
      resolve(new Result(code, signal))
    })

    proc.once('error', (err) => {
      reject(err)
    })
  })
  return new Command(result, killCommand)

  function onProcessExit() {
    killCommand('SIGTERM')
  }

  function killCommand(signal) {
    process.removeListener('exit', onProcessExit)
    if (proc) {
      proc.kill(signal)
      proc = null
    }
  }
}

// Exported to improve generated API documentation.