Scripts for connecting LyX with evince for backward/forward search

Scripts for connecting LyX with evince for backward/forward search

The scripts have been initially developed by Benjamin Kellermann (2011)
as a derivation of gedit-synctex-plugin by José Aliste
(https://github.com/jaliste/gedit-synctex-plugin, 2010) and published on
https://ubuntuforums.org/showthread.php?t=1716268.

The work here is based on a further derivation of this work for Sublime
Text LaTeX Tools
(https://github.com/SublimeText/LaTeXTools/tree/master/evince).

Adaptations for the use with LyX as well as the initial translation of
the evince_sync bash script to python have been done by myself.

The python code (particularly evince_sync_lyx) needs audit!