killp

Kill processes listening on one or more TCP ports.

npx killp 3000
npx killp 3000 8080

Or install the command globally:

npm install -g killp
killp 3000

Supports macOS and Linux. Requires /bin/sh, lsof, xargs, kill, and tr on your system. There are no npm dependencies. Windows is not supported.

This command immediately sends SIGKILL to every process listening on the specified TCP ports, without confirmation or graceful shutdown. Only use it on processes you intend to force-stop. Your user must have permission to stop them.

With no arguments, it prints usage and exits with status 2. Nonnumeric arguments are rejected. Port ranges are not validated, and an lsof error can be reported as “nothing listening.”

Development

The executable is the standalone POSIX shell script killp. It can also be run directly as ./killp PORT [PORT ...] without Node.js.

Run npm test to check the package contents, command usage, invalid input, and termination of a disposable listener through npx. The tests use Node.js 24+. Run npm publish ./killp-VERSION.tgz to publish the tested tarball.

License

MIT, starting with version 0.1.1. Version 0.1.0 was published under ISC.