System

1 min read

Import: import system;

Read the usage guide for examples and common tasks. This reference lists the public declarations for this part of the library. See Reading API signatures for parameter and result notation.

print

Writes and flushes a value as console text, as a shortcut for System.stdout.

public static extern fun print<T>(borrow value: T): void

println

Writes and flushes a value followed by a newline, as a shortcut for System.stdout.

public static extern fun println<T>(borrow value: T): void

read_line

Reads a line of input from stdin.

public static fun read_line(): string

read_key

Reads a single keypress from stdin.

public static fun read_key(): char

exit

Terminates the process with the given exit code.

public static fun exit(code: int): void

platform

The current host platform.

public static get platform(): Platform

os_family

The OS family on native hosts (Unknown elsewhere).

public static get os_family(): OsFamily

cpu_time_nanos

User+system CPU time of this process since it started, in nanoseconds (0 if unknown).

public static get cpu_time_nanos(): long

memory_bytes

Resident process memory in bytes (0 if unknown). Not Debug.live_objects.

public static get memory_bytes(): long

exe_path

Absolute path of the running executable when known.

public static get exe_path(): Option<string>

env

Value of environment variable name, or None when unset.

public static fun env(borrow name: string): Option<string>

set_env

Sets environment variable name to value.

public static fun set_env(borrow name: string, borrow value: string): Result<Unit, ArgumentError>

unset_env

Unsets environment variable name.

public static fun unset_env(borrow name: string): Result<Unit, ArgumentError>

env_keys

Names of all environment variables (empty on hosts without an env block).

public static get env_keys(): string[]

temp_dir

Process temp directory (TMPDIR / GetTempPath / "/tmp" in the browser).

public static get temp_dir(): string

home_dir

User home directory when the host provides one.

public static get home_dir(): Option<string>

cwd

Current working directory.

public static get cwd(): Result<string, IoError>

set_cwd

Sets the current working directory.

public static fun set_cwd(borrow path: string): Result<Unit, IoError>

clear

Clears the terminal screen.

public static fun clear(): void

set_foreground

Sets the foreground color for subsequent output.

public static fun set_foreground(color: ConsoleColor): void

set_background

Sets the background color for subsequent output.

public static fun set_background(color: ConsoleColor): void

reset_color

Resets console colors to the terminal default.

public static fun reset_color(): void