Scheduling

Scheduling: Scheduled Jobs: cron, Scripts That Run Without You.

Updated

  1. Scheduled Jobs: cron (Journeyman): cron runs commands at the times you set, even when you aren't at the keyboard: each line of your crontab has five time fields, minute, hour, day of the month, month and day of the week, then the command; crontab -e edits it, crontab -l shows it, and a job's output goes into a log file you name.
  2. Scripts That Run Without You (Freelancer): cron runs a script from your home folder, with a short PATH, no terminal and no keyboard, so a script that works when you type it can fail at 18:00; give it full paths and a PATH of its own, write everything to a log with the date and time, never ask a question, and take a lock with flock so two copies never run at once.