Ubuntu

squid

?

service

service squid start

service squid stop

squid.conf

/etc/squid3/squid.conf

error_directory

/usr/share/squid3/errors/Japanese

OSX (Homebrew)

squid

/usr/local/sbin/squid

squid.conf

/usr/local/etc/squid.conf

log

/usr/local/var/logs/

error_directory

/usr/local/opt/squid/share/errors/ja-jp

pid

/usr/local/var/run/squid.pid

auth programs

basic (NCSA)
/usr/local/opt/squid/libexec/basic_ncsa_auth

digest
/usr/local/opt/squid/libexec/digest_file_auth