English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I found the following variations on the use of "command line" and "shell" in computing and wonder which are correct and how to use them appropriately.

  • Command line: is it "at the command line" or "on the command line"?
  • Shell: is it "in a shell", inside a shell", "at a shell" or "on a shell"?

My English teacher once jokingly said that with prepositions it's not only knowledge but sometimes also a good portion of luck for those who aren't native speakers.

share|improve this question
@jwpat7 this I must have missed. Thank you! :) – user41720 Apr 2 '13 at 22:00
Also see ELL's When I should use “into”, “in”, “by” and “through”?, re running commands at a prompt. – jwpat7 Apr 2 '13 at 22:16
I like what your English teacher said. I also like to mention on occasion that there are some instances where there is no "right" preposition, but two or three that might be valid. "We met him at/in the bowling alley, on/at Lane 12," e.g. – J.R. Apr 3 '13 at 0:35
up vote 4 down vote accepted

One normally runs commands in a shell, not the others that you have listed.

However, if you had the shell’s process ID and sent that PID a signal of some sort, one could be said to have run the kill(1) command on that shell, in the sense of against it. Presumably the shell that you ran your kill in and the one you ran it on were different shells.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.