54     private $callback;  variable in Symfony\\Component\\Process\\Process
238      * @param callable|null $callback A PHP callback to run whenever there is some
251     public function run(?callable $callback = null, array $env = []): int  argument
253         $this->start($callback, $env);
270     public function mustRun(?callable $callback = null, array $env = []): self  argument
272         if (0 !== $this->run($callback, $env)) {
291      * @param callable|null $callback A PHP callback to run whenever there is some
298     public function start(?callable $callback = null, array $env = [])  argument
306         $this->callback = $this->buildCallback($callback);
307         $this->hasCallback = null !== $callback;
377      * @param callable|null $callback A PHP callback to run whenever there is some
389     public function restart(?callable $callback = null, array $env = []): self  argument
396         $process->start($callback, $env);
408      * @param callable|null $callback A valid PHP callback
416     public function wait(?callable $callback = null)  argument
422         if (null !== $callback) {
427             $this->callback = $this->buildCallback($callback);
459     public function waitUntil(callable $callback): bool  argument
468         $callback = $this->buildCallback($callback);
478 …               $ready = $callback(self::STDOUT === $type ? self::OUT : self::ERR, $data) || $ready;
636 …while (null !== $this->callback || ($yieldOut && !feof($this->stdout)) || ($yieldErr && !feof($thi…
1310      * @param callable|null $callback The user defined PHP callback
1314     protected function buildCallback(?callable $callback = null)  argument
1317             return function ($type, $data) use ($callback): bool {
1318                 return null !== $callback && $callback($type, $data);
1324         return function ($type, $data) use ($callback, $out): bool {
1331             return null !== $callback && $callback($type, $data);
1441         $callback = $this->callback;
1444                 $callback(self::STDOUT === $type ? self::OUT : self::ERR, $data);
1478         $this->callback = null;
1489         $this->callback = null;