What is hup signal? How to send one to squid?
 

Dear All,

I tried to follow an instruction that says:
"send Squid a HUP signal to respawn squidGuard"

What is mean by that and how should I carry it out?

Thanks in advance,

man kill will help you out here. Kill is actually slightly mis-named, it doesn't necessarily terminate a process, it sends it a signal of a particular type. A signal is just a way of notifying a running program that something has happened, like an invalid memory access or an interrupted system call or whatever (see kill -l for a list of all signals). Anyhow, to make a very long story short, to send SIGHUP to squid, you would do

kill -HUP <pid of squid>

or, to save yourself from having to look up the PID:

killall -HUP squid

Thank you very much btmiller,