HAVP (HTTP Antivirus Proxy) is a proxy with a ClamAV anti-virus
scanner.  The main aims are continuous, non-blocking downloads and
smooth scanning of dynamic and password protected HTTP traffic. Havp
antivirus proxy has a parent and transparent proxy mode. It can be
used with squid or standalone.

This requires mandatory locks on the scanning find system unless you
add --disable-locking to the configuration (enabled by default for
performance).

Also, see README.setup for some configuration hints.

You need an "havp" user (and a "clamav" group, due to the dependency on 
clamav) to be present during compilation and installation.
Suggested means of accomplishing this are as follows:
  groupadd -g 210 clamav
  useradd -u 256 -d /dev/null -s /bin/false -g clamav havp