efax - 1:0.9a-19.1 main

efax is a small ANSI C/POSIX program that provides the data transport
function for fax applications using any Class 1 or Class 2 fax modem.
Another program, efix, converts between fax, text, bitmap and grayscale
formats. fax, a shell script, provides a simple user interface to the efax
and efix programs. It allows you to send text or Postscript files as faxes
and receive, print or preview received faxes.
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The ghostscript package is needed to fax Postscript files, and an image
viewing program like xloadimage is needed to view incoming faxes.
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Note that you probably have to adapt /etc/efax.rc to your needs.