faxmail is designed for use in constructing electronic mail to facsimile gateway services. For example, mail aliases may be created to automatically transmit electronic mail; e.g.
sam: "|/usr/bin/faxmail -d sam@5551212"or faxmail may be used as a ``mail transport agent'', extracting the necessary delivery information directly from the envelope of the mail message.
If faxmail is invoked without enabling direct delivery then it just formats the mail message on the standard input and writes the result to the standard output. To enable direct delivery the -d option must be specified on the command line; see below for more information.