IsRunning

IsRunning is a very simple and lightweight Windows command-line utility to check if some processes are running or not.

It expects a list of process's names as argument and simply exits with code 0 if they were found, or 1 otherwise. No output or message is printed.

Usage:

IsRunning.exe PROCESS_1 [PROCESS_2] [PROCESS_N]

Examples

C:\> IsRunning.exe traefik.exe
C:\> echo %errorlevel%
0

C:\> IsRunning.exe traefik.exe node.exe
C:\> echo %errorlevel%
0

C:\> IsRunning.exe dead.exe
C:\> echo %errorlevel%
1

Motivation

Its main purpose is to serve as readiness probe for containers that spawn multiple processes.

For example, a Pod readiness probe to detect if traefik is running:

    readinessProbe:
      exec:
        command:
        - C:/IsRunning.exe
        - traefik.exe
      failureThreshold: 3
      periodSeconds: 5
      successThreshold: 1
      timeoutSeconds: 5

It's not advisable to run multiple processes on a single container, but for many reasons, it's not uncommon, especially for legacy applications in Microsoft Windows containers.

Why not use batch script?

I used to use a batch script combining tasklist and find together:

C:\> tasklist | find "traefik.exe"
C:\> echo %errorlevel%
0

It works, but it's not the most efficient solution, particularly when you call it every 5 seconds for hundreds of containers.

This utility saves a little bit of CPU and memory by removing the overhead of CMD interpreter and all the string processing between tasklist and find.

This utility is implemented in Zig, just because we needed a native, small, fast, and secure binary to perform such task.

Limitations

• Windows only application

• It is optimized for low memory consumption, and only works with ASCII processes names.

Please, feel free to open an issue or send a PR if you might improve this implementation in some sense.