src/UnixEnvironment.php
private function safeSendSignal($process, string $signal, int $mappedSignal): void
    {
        if (true !== proc_terminate($process, $mappedSignal)) {
            throw new CommandExecutionException(
                'Call to proc_terminate with signal "' . $signal . '" failed for unknown reason.'
            );
        }
    }
private function safeSendSignal($process, string $signal, int $mappedSignal): void
    {
        if (true !== proc_terminate($process, $mappedSignal)) {
            throw new CommandExecutionException(
                'Call to proc_terminate with signal "' . $signal . '" failed for unknown reason.'
            );
        }
    }
private function safeSendSignal ( $ process , string $ signal , int $ mappedSignal ) : void { if ( true !== proc_terminate ( $ process , $ mappedSignal ) ) { throw new CommandExecutionException ( 'Call to proc_terminate with signal "' . $ signal . '" failed for unknown reason.' ) ; } }
'Safe' send signal method; throws an exception if the signal send fails for any reason.

@throws CommandExecutionException on error.
Safe send signal method ; throws an exception if the signal send fails for any reason .