Why I've got no crontab entry on OS X when using vim?

Question

I would like to use cron on my Mac. I choose it over launchd, because I want to be able to use my new knowledge on Linux as well. However, I cannot seem to get

Answer 1

As the previous posts didn't work for me because of some permissions issues, I found that creating a separate crontab file and adding it to the user's crontab with the -u parameter while root worked for me.

sudo crontab -u {USERNAME} ~/{PATH_TO_CRONTAB_FILE}