std/process

std/process provides access to the running process — arguments, working directory, and exit control.

API

pub ext fun exit(code: Int) Void;
pub ext fun argc() Int;
pub ext fun argv(i: Int) String;
pub ext fun exec(cmd: String) Int;
pub ext fun cwd() String;

pub fun panic(message: String) Void;

Function	Description
argc()	Returns the number of command-line arguments
argv(i)	Returns the argument at index i (0 = program name)
cwd()	Returns the current working directory as a string
exit(code)	Exits the process with the given exit code
exec(cmd)	Runs a shell command, returns exit code
panic(msg)	Prints msg to stderr and exits with code 1

Examples

Reading command-line arguments

import "std/process";
import "std/io" { println, printInt };

fun main() Int {
    println("Program: " ~ process.argv(0));
    printInt(process.argc());

    var i: Int = 1;
    while i < process.argc() {
        println("arg: " ~ process.argv(i));
        i = i + 1;
    }

    return 0;
}

Run with: ./program foo bar → prints arg: foo, arg: bar.

Working directory and exit

import "std/process";
import "std/io" { println };

fun main() Int {
    println("Running in: " ~ process.cwd());

    if process.argc() < 2 {
        println("Usage: program <name>");
        process.exit(1);
    }

    println("Hello, " ~ process.argv(1) ~ "!");
    return 0;
}