/**
* Starts the process and returns after sending the STDIN.
*
* This method blocks until all STDIN data is sent to the process then it
* returns while the process runs in the background.
*
* The termination of the process can be awaited with wait().
*
* The callback receives the type of output (out or err) and some bytes from
* the output in real-time while writing the standard input to the process.
* It allows to have feedback from the independent process during execution.
* If there is no callback passed, the wait() method can be called
* with true as a second parameter then the callback will get all data occurred
* in (and since) the start call.
*
* @param callback|null $callback A PHP callback to run whenever there is some
* output available on STDOUT or STDERR
*
* @throws RuntimeException When process can't be launch or is stopped
* @throws RuntimeException When process is already running
*/
public function start($callback = null)
{
if ($this->isRunning()) {
throw new RuntimeException('Process is already running');
}
$this->resetProcessData();
$this->starttime = microtime(true);
$this->callback = $this->buildCallback($callback);
$this->processPipes = new ProcessPipes($this->useFileHandles);
$descriptors = $this->processPipes->getDescriptors();
if (!$this->useFileHandles && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
// last exit code is output on the fourth pipe and caught to work around --enable-sigchild
$descriptors = array_merge($descriptors, array(array('pipe', 'w')));
$this->commandline = '(' . $this->commandline . ') 3>/dev/null; code=$?; echo $code >&3; exit $code';
}
$commandline = $this->commandline;
if (defined('PHP_WINDOWS_VERSION_BUILD') && $this->enhanceWindowsCompatibility) {
$commandline = 'cmd /V:ON /E:ON /C "' . $commandline . '"';
if (!isset($this->options['bypass_shell'])) {
$this->options['bypass_shell'] = true;
}
}
$this->process = proc_open($commandline, $descriptors, $this->processPipes->pipes, $this->cwd, $this->env, $this->options);
if (!is_resource($this->process)) {
throw new RuntimeException('Unable to launch a new process.');
}
$this->status = self::STATUS_STARTED;
$this->processPipes->unblock();
$this->processPipes->write(false, $this->stdin);
$this->updateStatus(false);
$this->checkTimeout();
}
/**
* Creates the descriptors needed by the proc_open.
*
* @return array
*/
private function getDescriptors()
{
$this->processPipes = new ProcessPipes($this->useFileHandles, $this->tty);
$descriptors = $this->processPipes->getDescriptors();
if (!$this->useFileHandles && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
// last exit code is output on the fourth pipe and caught to work around --enable-sigchild
$descriptors = array_merge($descriptors, array(array('pipe', 'w')));
$this->commandline = '(' . $this->commandline . ') 3>/dev/null; code=$?; echo $code >&3; exit $code';
}
return $descriptors;
}
/**
* Creates the descriptors needed by the proc_open.
*
* @return array
*/
private function getDescriptors()
{
$this->processPipes = new ProcessPipes($this->useFileHandles, $this->tty);
return $this->processPipes->getDescriptors();
}
