How to debug squid?

I want to debug my squid 1.1.17. But I don't know how to make the debug(...)
output information to stderr or syslog. Should I set some environment variables
or sth. else?

------
Chen Yantao

Institute of Software Email : cyt@ox.ios.ac.cn
Academia Sinica of China Address : PostBox No.8718, Beijing PRC
                                Telephone: 86-10-62556910
                                           86-10-62565533-7111
Received on Mon Dec 01 1997 - 18:10:51 MST