Efax-gtk is a free fax application available on sourceforge. It has a socket interface which means that to Synapse it can appear as a printer.
Synapse-linux R213B41.8 adds a "Local Efax" button on the fax applet. This sends the current document to 127.0.0.1:9900 where efax-gtk should be listening when active. This then results in a efax-gtk requester asking for the telephone number. You can then ask for the document to be faxed immediately or added to the queue.
On Ubuntu, you can install efax-gtk simply by
sudo apt-get install efax-gtk
It can then be started from the Applications/Office/Efax-gtk menu. It will also then appear in the system tray at the top right - as a fax/phone icon.
To use efax-gtk, you will of course need a fax modem attached, preferably on ttys0.
To configure it, use the File/Settings menu, and make sure that you enable the socket server on the "Socket" tab.
Graham Chiu
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