[squid-users] access.log

[Ilya]

Hello!

Can you explain what the "rfc931" (http://www.squid-cache.org/Doc/FAQ/FAQ-6.html#ss6.6) field in access.log format is responsible for? Is this the username of user who passed the squid authentication program (authenticate_program in squid.conf)?

Thanks a lot.
Ilya.