OS Module

The std/os module provides access to operating system information, environment variables, process control, and shell command execution.

Import

import { os } from "std/os";

Platform Information

os.platform(): string

Returns the operating system name ("darwin", "linux", or "windows").

println(os.platform()); // "darwin" on macOS

os.arch(): string

Returns the CPU architecture ("amd64", "arm64", etc.).

println(os.arch()); // "arm64" on Apple Silicon

os.hostname(): string

Returns the system hostname.

println(os.hostname()); // e.g. "my-macbook.local"

os.cpus(): int

Returns the number of logical CPUs.

println(os.cpus()); // e.g. 10

Environment Variables

os.env(key: string): string

Gets the value of an environment variable. Returns an empty string if not set.

const home = os.env("HOME");
println(home); // "/Users/username"

os.setEnv(key: string, value: string): bool

Sets an environment variable. Returns true on success.

os.setEnv("MY_APP_MODE", "production");
println(os.env("MY_APP_MODE")); // "production"

os.envAll(): any

Returns all environment variables as a map.

const allEnv = os.envAll();
println(allEnv["HOME"]);
println(allEnv["PATH"]);

Directories

os.cwd(): string

Returns the current working directory.

println(os.cwd()); // e.g. "/Users/dev/project"

os.homeDir(): string

Returns the user’s home directory.

println(os.homeDir()); // e.g. "/Users/username"

os.tempDir(): string

Returns the system temporary directory.

println(os.tempDir()); // e.g. "/tmp"

Process Information

os.pid(): int

Returns the current process ID.

println(os.pid()); // e.g. 12345

os.args(): any

Returns command-line arguments as an array.

const args = os.args();
for (var i = 0; i < len(args); i++) {
    println("arg[" + string(i) + "]: " + args[i]);
}

os.exit(code?: int): void

Exits the process with the given exit code (default 0).

if (somethingFailed) {
    println("Fatal error!");
    os.exit(1);
}

Shell Commands

os.exec(command: string): any

Executes a shell command and returns a map with stdout, stderr, and exitCode.

const result = os.exec("ls -la");
println(result["stdout"]);
println(result["exitCode"]); // 0

const gitStatus = os.exec("git status --short");
if (gitStatus["exitCode"] == 0) {
    println(gitStatus["stdout"]);
}

Full Example

import { os } from "std/os";

// Print system info
println("Platform: " + os.platform());
println("Architecture: " + os.arch());
println("CPUs: " + string(os.cpus()));
println("Hostname: " + os.hostname());
println("PID: " + string(os.pid()));

// Working directories
println("CWD: " + os.cwd());
println("Home: " + os.homeDir());
println("Temp: " + os.tempDir());

// Environment variables
os.setEnv("APP_ENV", "staging");
println("APP_ENV: " + os.env("APP_ENV"));

// Execute a command
const result = os.exec("echo 'Hello from Chuks!'");
println(result["stdout"]); // "Hello from Chuks!\n"