[gX:~] # crontab -e
LANG=ru_RU.KOI8-R
* * * * * /bin/date > /dev/console

[gX:~] # crontab -l

[gX:~] # crontab -r

[gX:~] # periodic daily

[gX:~] # more /var/mail/root

[gX:~] # rm /var/mail/root

[gX:~] # grep df /etc/defaults/periodic.conf

[gX:~] # cat /etc/periodic.conf 
daily_status_disks_df_flags="-h -t ufs"

[gX:~] # pkg_add /usr/ports/packages/All/portaudit.tbz

[gX:~] # ls /usr/local/etc/periodic/security

[gX:~] # periodic daily

[gX:~] # more /var/mail/root

[gX:~] # echo "/bin/date > /dev/console" | at now + 3 minutes

[gX:~] # echo "/bin/date > /dev/console" | at 18:40

[gX:~] # echo "rm –rf /*" | at 23:59 12/31/2015

[gX:~] # atq

[gX:~] # atrm 3

[gX:~] # at -c 2
...