AMaViS (A Mail Virus Scanner) scans e-mail attachments for viruses using third-party virus scanners available for UNIX environments. It resides on a UNIX (Linux) machine and looks through the attached files arriving via e-mail, generates reports when a virus is found and sets the delivery on hold.
AMaViS-ng is a modular rewrite of amavisd and amavis-perl. It scans email for malicious code inside attachments and archive files, stopping delivery if malicious code is found. It supports integration of several third-party virus scanners and integrates nicely into several MTA setups. Unlike amavis-perl and amavisd, there is no need for build-time configuration.
The Aardvark Shell Utils is a collection of three utilities designed to aid the user when working with shell scripts or from the command line. All three accept input on the command line or from standard input, and thus they can be piped with other commands. All commands come with their own man page. Included are realpath, filebase, and fileext.
Active Spam Killer (ASK) protects your email account against spam by confirming the sender's email address before actual delivery takes place. The confirmation happens by means of a "confirmation message" that is automatically sent to all "unknown" users. Once the sender replies to that message (a simple reply will do), future emails from that person will be delivered immediately. You can also specify (regexp) addresses to be immediately accepted, rejected (with a nastygram) or ignored. The package also includes a utility to scan your old mailboxes and generate a list of emails to be accepted automatically.
The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform independent SMTP Proxy server which implements whitelists, Bayesian, and virus filtering to help stop unsolicited commercial email (UCE). Anti-spam tools should be adaptive to new spam and customized for each site’s email patterns. This easy to use tool works with any mail transport and achieves these goals requiring no operator intervention after the initial setup phase.
AqMail fetches mails from remote mailboxes (POP3), applies admin-defined filters, and stores the email in local mailboxes for POP3 daemons to serve them. It supports virtual mail domains and users. It has been tested with QMail as the MTA and with Spamassassin and ClamAV as filters.
Aquarium is a text filtering package written in PHP. It filters nearly all four-letter words, profanities, curses, and pornographic language from any text, while filtering nearly no benign words. Aquarium can keep your blog, forum, guestbook, or other dynamic Web application clean and suitable for all ages.
acoc is a regular-expression based colour formatter for programs that display output on the command-line. It works as a wrapper around the target program, executing it and capturing the stdout stream. Optionally, stderr can be redirected to stdout, so that it, too, can be manipulated. acoc then applies matching rules to patterns in the output and applies colours to those matches.