php apache "You do not have permission to use at.

Shell
// 1) Check if you have file /etc/at.allow.
// If youre using apache, your user is "www-data"
// If it exists - just add your user in new line.
// If not exists - try to find your user in /etc/at.deny and remove/comment it.
// 2) Restart "at" daemon:
sudo atd restart
// 3) Check:
at -l
// or
sudo -u myuser at -l
// The error should not be output.
Source

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