SpamAssassin

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<hide> page type::article thing type::software function::spam filtering architecture::client-server license::open source platform::Microsoft Windows platform::Linux </hide>

About

SpamAssassin is open source software for filtering spam.

It consists of two main executables, the spamd daemon and the spamc client (manpage). Email programs (such as postfix) needing to filter messages will call spamc and pass the message data to it; spamc reads the mail from stdin, spools it to its connection to spamd, then reads the result back and prints it to stdout.[1]