Run a script after some command were executed

Question

I have a list of scripts

• ./myscript <param> | grep "asd"

• ./myotherscript <param> <param> > file

• ...

How can I automaticaly run another script when one of these command in the list is executed and finished?

Answer 1

There are multiple ways to automatically execute something after a specific command:

function

Create a function named after your specific command and execute the specific command afterwards. This is in my opinion the simplest and cleanest solution.

function myotherscript() {
   command myotherscript "$@"
   other_command_to_be_executed
}

zsh

With zsh you can create a precmd function which will be executed before the prompt. This allows you to execute arbitrary other commands but you'll have to determine the executed command yourself.

function precmd() {
   last_cmd=$(history -1 |  sed -e "s/^[ ]*[0-9]*[ ]*//g")
   case "$last_cmd" in
   *myscript*) other_command;;
   *myotherscript*) other_other_command;;
   esac
}

bash

Bash has the PROMPT_COMMAND variable allowing you to implement your own precmd function. To use it you have to set it to a command which will be executed before the prompt:

PROMPT_COMMAND="${PROMPT_COMMAND};bash_precmd"

function bash_precmd() {
  last_command=$(history 1 | sed -e "s/^[ ]*[0-9]*[ ]*//g")
  case "$last_command"  in
  *pattern*) command ;;
  esac
}

If you are using bash and want to use something like preexec or precmd have a look at precmd and preexec with bash