From what I remember, using
acl aclname time [day-abbrevs] [h1:m1-h2:m2] in the squid.conf file used whatever time setting your box did - is your Linux box using GMT or UTC?
As far as parsing the logs goes, it's easier to use a tool like
calamaris to generate and format a report. Alternatively, to just pull out the first, fourth and seventh fields of the access log you could do this:
Code:
awk '/192\.168\.1\.20/ {print strftime("%c",$1),$4,$7}' /var/log/squid/access.log