env

env

The env module reports basic process and host information: whether an environment variable is set, the current working directory, and the operating system name and CPU architecture.

Import

use std::core::env

Functions

env::has(name: string) -> bool

Check whether an environment variable is set.

if env::has("API_KEY") {
    print("API key configured")
}

env::cwd() -> string

Get the absolute path of the current working directory.

let dir = env::cwd()
print(dir)

env::os() -> string

Get the operating-system name — typically "linux", "macos", or "windows".

let name = env::os()
print(name)

env::arch() -> string

Get the CPU architecture — typically "x86_64" or "aarch64".

let arch = env::arch()
print(arch)

Function Reference

Function	Signature	Description
env::has(name)	(string) -> bool	Variable is set
env::cwd()	() -> string	Current working directory
env::os()	() -> string	Operating-system name
env::arch()	() -> string	CPU architecture

Note

The env stdlib source also declares env::get, env::all, and env::args, but their native bindings are not wired up at HEAD — calling them is a compile error (module 'env' has no export ...). They are tracked as a follow-up to the typed-marshal layer (Option<string>, HashMap, and Array<string> return marshalling). Until they ship, use env::has to test for a variable’s presence.

Permissions

Every env function requires the Env permission. In a sandboxed scope without Env, a call to env::has, env::cwd, env::os, or env::arch fails with a permission error rather than returning a value.

See Also

• Security & Permissions — the Env permission