Process

The Process component provides a typed, non-blocking API for spawning and managing child processes, built on top of PSL's IO system.

It serves as an alternative to proc_*, symfony/process, and amphp/process, with an API inspired by Rust's std::process module adapted to PSL conventions.

Usage

@example('io/process-output.php')

Command Construction

Command is an immutable builder. All with*() methods return a new instance.

• Command::create(string $program) -- executes a program directly, bypassing the shell. Prevents shell injection and is the recommended approach.
• Command::shell(string $command) -- interpreted by the system shell (/bin/sh -c on Unix, cmd.exe on Windows). Allows pipes, globbing, and variable expansion.

Stdio Configuration

Stdio controls what happens with each standard I/O stream:

• Stdio::piped() -- pipe between parent and child (default for stdout/stderr)
• Stdio::inherit() -- child inherits the parent's descriptor
• Stdio::null() -- attach to /dev/null (default for stdin)
• Stdio::tty() -- connect directly to the terminal, useful for interactive programs (Unix only)
• Stdio::fromStreamHandle($handle) -- use an existing stream handle

Examples

Collect Output

@example('io/process-collect-output.php')

Check Exit Status

@example('io/process-exit-status.php')

Write to Stdin

@example('io/process-stdin.php')

Shell Commands

@example('io/process-shell.php')

Cancellation

@example('io/process-timeout.php')

Signals

@example('io/process-signals.php')

Environment Variables

@example('io/process-environment.php')

Non-Blocking Poll

@example('io/process-poll.php')

See src/Psl/Process/ for the full API.