E-Mail Virus Scanning Options on Unix/Linux

The Goal

The Players

• Sophos Anti-Virus - a commercial product that handles virus scanning on a ton of platforms. There's a lot of free stuff that makes use of this too, mostly becuaes the've published their API and a SDK.
• Sophie - A daemon that makes use of libsavi which is provided by Sohpos. Sophie clients communicate with the server using a local unix socket.
• AMaViS - A Mail Virus Scanner. It has been around a while and supports all popular MTAs. It has a good community of support. Makes use of various back-end virus software, such as Sophos. The author's RubiCon presentation is interesting.
• exiscan - An Exim-specific scanner. For Exim version 3, there is a Perl package. For Exim version 4, there is a patch to the Exim source that makes use of Exim's local_scan() API. Ultimately, exiscan will call an external virus scanner.
• Clam Antivirus - A relative new-comer, Clam is a multi-threaded scanner written in C. It uses the freely available virus signatures from the OpenAntivirus project. Clam has handy auto-update facility and a patch to add Clam support to AMaViS.
• F-Prot - Virus scanning for Linux and Windows. There's a per-server license cost of roughly $300 or $450 annually.

My Testing