math

basic

echo "$(expr $AGE + 10) years old."

comparison

/root/scripts/restart-php-fpm:
#!/bin/bash
if (( $(pgrep php5-fpm | wc -l) > 90)); then service php5-fpm restart; fi

chmod +x /root/scripts/restart-php-fpm

crontab -l:
* * * * * /root/scripts/restart-php-fpm