runtime:system

Child processes. A command is a program plus an argv — there is no shell, so nothing is word-split, glob-expanded, or re-parsed. Output moves over web streams.

Import

import { Command } from "runtime:system";

// Or the default aggregate:
import system from "runtime:system";

Exports

new Command(program, options?)

program is a path (absolute, or relative to cwd) or a bare name looked up on the host PATH. The env you pass describes the child's environment, never where the runtime looks for executables.

options is an object with only the keys below. An array (Node's spawn(cmd, args) shape) or any other key is a TypeError, so a misplaced argument list is never silently dropped.

CommandOutput is { success, code, signal, stdout, stderr } — code is null when a signal ended the process, stdout/stderr are Uint8Array.

ChildProcess

Examples

import { Command } from "runtime:system";

// Buffered
const { success, code, stdout } = await new Command("git", {
  args: ["rev-parse", "HEAD"],
}).output();

// Streaming, both ways
const child = await new Command("ffmpeg", {
  args: ["-i", "pipe:0", "-f", "mp3", "pipe:1"],
  stdin: request.body,
  stderr: "inherit",
}).spawn();
return new Response(child.stdout);

// Bounded
await new Command("slow-tool", { timeout: 30_000, killSignal: "SIGKILL" }).output();

Not provided