13 Pmilter multiplexer program.

Pmult is a Pmilter–Milter multiplexer, i.e. a program that acts as a mediator between the Pmilter server and one or several Milter clients. Usually, the former is an instance of smtps from MeTA1, and the latter are running mailfromd instances. Pmult receives Pmilter commands from the server, translates them into equivalent Milter commands and passes the translated requests to a preconfigured set of Milter filters. When the filters reply, the reverse operation is performed: Milter responses are translated into their Pmilter equivalents and are sent back to the server.

                                            +-----------------+ 
                                     +----->| Milter Client 1 |
                                     |      +-----------------+ 
                                     |       
   +-----------+       +---------+   |      +-----------------+ 
   |   MeTA1   |<=====>|  Pmult  |<--+----->| Milter Client 1 | 
   +-----------+       +---------+   |      +-----------------+ 
                                     |
                                     +--------->    //
                                     |
                                     |      +-----------------+  
                                     +----->| Milter Client N | 
                                            +-----------------+

Due to the specifics nature of the threaded MeTA1 libraries, pmult does not detach from the controlling terminal (i.e. does not become a daemon). To run it as a background process, we recommend to use pies daemon. ‘Pies’ is a powerful utility that allows you to launch several foreground-designed programs in the background and control their execution. See Pies in Pies Manual, for a detailed description of the program. For a practical advice on how to use it with pmult, see Using Pies to Run Pmult in Pies Manual. For a description on how to start both pmult and MeTA1 from the same pies configuration file, see Using Pies to Run Pmult and MeTA1 in Pies Manual.