osascript-subprocess

name	osascript-subprocess
description	Run subprocesses from JXA/osascript using NSTask. Use when you need separate stdout/stderr streams, async execution, stdin piping, kill signals, exit codes, or running uv Python scripts from within a JXA automation script.

osascript-subprocess

NSTask via JXA ObjC bridge — full POSIX process control from within osascript. All scripts are Python with JXA embedded as strings.

NSTask vs doShellScript

	doShellScript	NSTask
Execution	Synchronous, blocks	Sync or async
stderr	Merged or lost	Separate NSPipe
stdin	None	NSPipe — writable
Kill process	Cannot	task.terminate()
Exit code	Only via error	task.terminationStatus
Long-running	Blocks script	Background option

Use doShellScript for quick one-liners. Use NSTask when you need stderr, stdin, kill, or async.

PATH Note

uv lives in /opt/homebrew/bin. Always set PATH explicitly in NSTask — it does not inherit shell PATH:

task.environment = $.NSDictionary.dictionaryWithObjectsAndKeys(
    $("/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin"), $("PATH"),
    ...
);

Use /usr/bin/env as launchPath with ["uv", "run", ...] as arguments — lets env resolve uv from PATH.

Scripts

Run any shell command via NSTask — returns {stdout, stderr, exitCode}:

uv run scripts/run-command.py "ls -la /tmp"
uv run scripts/run-command.py "ping -c 3 google.com"

Run a uv run Python script via NSTask with proper PATH resolution:

uv run scripts/run-uv-script.py /path/to/script.py arg1 arg2

Reference

• reference/21-nstask.md — Full NSTask API, stdin/stdout/stderr pipes, async, kill, env vars, uv pattern
• reference/01-languages-and-execution.md — Python wrapper patterns, doShellScript vs NSTask decision