I want to run a job with cron on reboot as a particular user. I have been able to do this successfully using crontab to write to /var/spool/cron/crontabs/username with something like:

 @reboot ./run.sh >>~/tracefile 2>&1

However, I want to use /etc/cron.d/filename. Cron jobs in this file require an extra column to indicate what user runs, so I use:

 @reboot wwwuser ./run.sh >>~/tracefile 2>&1

This doesn't seem to work. Should I be able to use @reboot with a username in a cron.d file?