Linux: Get crontab and /etc/cron.* scripts

Crontab is the program used to install, remove or list the tables used to drive the cron(8) daemon. Each user can have their own crontab, and though these are files in /var/spool/, they are not intended to be edited directly. For SELinux in mls mode can be even more crontabs - for each range. Many of the services use crontab automatically. They store their crontab scheduler configuration directly into /etc/cron.d directory. Any files located in this directory are automatically picked up and executed by the crontab scheduler. Linux system administrators can also take an advantage of crontab preconfigured schedules directories /etc/cron.daily, /etc/cron.hourly, /etc/cron.monthly and /etc/cron.weekly. The crontab files located within these directories are periodically traversed and execute by crontab scheduler. So for example crontab files found in /etc/cron.daily directory are executed every day. Furthermore, if root wishes to run eg. backup.sh script once a week he will place it into /etc/cron.weekly directory. Note: This script gets the crontab for root user and content of files /etc/cron.*