Process

Command Execution

import process

Running Commands

Function	Signature	Description
runCommand	(cmd: String) r: CommandResult	Execute shell command, capture output
runProgram	(path: String) r: Int	Execute program, return exit code
execCommand	(cmd: String) r: Int	Execute command, return exit code
runCommandOutput	(cmd: String) r: String	Execute and return stdout
runCommandOrAbort	(cmd: String) r: Void	Execute, abort on failure

CommandResult

Function	Description
commandWasSuccessful(result)	Check if command succeeded
commandOutput(result)	Get stdout output
isSuccess(result)	Check exit code == 0

Example

let result = runCommand("ls -la")
if commandWasSuccessful(result) {
    println(commandOutput(result))
}

let exitCode = runProgram("/usr/bin/gcc")

Process Management

Function	Signature	Description
processFork()	r: Int	Fork process (returns child PID in parent, 0 in child)
waitPid(pid: Int, flags: Int)	r: Int	Wait for child (0=blocking, 1=WNOHANG)
processExit(code: Int)	Void	Terminate process
getPid()	r: Int	Get current process ID

Note: Use processFork() instead of fork() to avoid shadowing POSIX fork().

Example

let pid = processFork()
if pid == 0 {
    // child process
    println("I'm the child")
    processExit(0)
} else {
    // parent process
    println("Child PID: {pid}")
    waitPid(pid, 0)
}

Environment Variables

import env

Function	Signature	Description
get	(name: String) r: String	Get env var (empty if missing)
has	(name: String) r: Bool	Check if env var exists
set	(name: String, value: String) r: Bool	Set env var
removeEnv	(name: String) r: Bool	Remove env var
tryGet	(name: String) r: Option<String>	Get env var as Option
getOrDefault	(name: String, default: String) r: String	Get with fallback

Example

let home = get("HOME")
println("Home: {home}")

if has("DEBUG") {
    println("Debug mode enabled")
}

set("MY_VAR", "hello")

Command-Line Arguments

let arguments = args()  // returns Array<String>
for arg in arguments {
    println(arg)
}

Shell Quoting

let safe = shellQuote("file with spaces.txt")
// Returns: 'file with spaces.txt'

Runtime Functions

Function	Description
__ExecuteProgram(path)	Execute program, return exit code
__seen_fork()	Fork process
__seen_waitpid(pid, flags)	Wait for child
__seen_exit(code)	Exit process
__seen_getpid()	Get PID
__HasEnv(name)	Check env var
__GetEnv(name)	Get env var
__SetEnv(name, value)	Set env var
__RemoveEnv(name)	Remove env var
seen_runtime_init(argc, argv)	Initialize runtime with args