As I grow from my front-end roots into a seasoned full-stacker, I often overlook the extracurricular skills that get added to my dev toolbox. One such skill would be devops (sysadmin). Little did I know the impact that learning my way around Linux, bash, GNU tools, and the like would have on my technical productivity. But along with learning these tools came many "gotcha" and "oh that's why it's not working" moments. This post stands as a reference for not only myself, but also as a helping hand to others trying to hack and deploy apps on their own terms. I plan to continually update this with things I learn regarding different GNU/*nix tools so that I do not repeat past mistakes.

Cron

Percent signs must be escaped.

Percent signs have special meaning in cron. Therefore to utilize them in a command, you must first escape them.

# crontab -e

# gives an error
*/1 * * * * echo $(date '+%Y%m%d')

# works as intended
*/1 * * * * echo $(date '+\%Y\%m\%d')