Simulating cron environment

Ever added a script to crontab just to discover it didn't run as expected? Well, cron environment is not the same as your user environment and that could make a huge difference depending what your script is doing.

To help me writing scripts taking into account this difference I use the following tip by mmccoo (https://stackoverflow.com/questions/2135478/how-to-simulate-the-environment-cron-executes-a-script-with).

Add this to crontab:

 
30 08 * * * env > ~/cronenv

After it runs, do this:

 
env - `cat ~/cronenv` /bin/sh

This assumes that your cron runs /bin/sh, which is the default regardless of the user's default shell.

If you want to use another shell just change /bin/sh for your favorite shell and don't forget to also change the shell used by cron by adding this to your crontab:

 
SHELL=<your_favorite_shell>