Signals

Using the Signal enum

<?php

use FastForward\Fork\Signal\Signal;

$group->kill(Signal::Terminate);

Available public signals

The enum currently exposes common POSIX signals used for process coordination, including:

• Signal::Interrupt
• Signal::Quit
• Signal::Terminate
• Signal::Kill
• Signal::User1
• Signal::User2
• Signal::Child
• Signal::Continue
• Signal::Stop
• Signal::TerminalStop

Signal workers directly

<?php

use FastForward\Fork\Signal\Signal;

$worker->kill(Signal::Terminate);
$worker->wait();

Signal a whole group

<?php

use FastForward\Fork\Signal\Signal;

$group->kill(Signal::Terminate);
$group->wait();

Signal a subset through the manager

<?php

use FastForward\Fork\Signal\Signal;

$manager->kill(Signal::Terminate, $groupA, $workerB);
$manager->wait($groupA, $workerB);

Default signal handling

DefaultSignalHandler is the built-in strategy for master-process signal propagation.

Its main behaviors are:

• subscribe to a configurable list of signals
• normalize interactive termination signals to Signal::Terminate for workers
• optionally wait for worker shutdown
• optionally exit the current process after handling
• escalate to Signal::Kill if a second signal arrives during shutdown

Example

<?php

declare(strict_types=1);

use FastForward\Fork\Manager\ForkManager;
use FastForward\Fork\Signal\DefaultSignalHandler;
use FastForward\Fork\Signal\Signal;

$manager = new ForkManager(
    signalHandler: new DefaultSignalHandler(exitOnSignal: false),
);

posix_kill($manager->getMasterPid(), Signal::Terminate->value);

Signal-aware exit status

Signal::exitStatus() converts a signal into the conventional shell exit status of 128 + signal_number .

This is useful when a signal handler decides to terminate the current process after propagating shutdown to workers.