based off winmerge 2.4.6 codebase.
this allows capable external editors to open any
compared files and automatically go to to the line
number that is selected in Winmerge.
eg: c:\editor.exe filename.cpp /900
usage: right click > open > with external editor
(TODO, not done) it would be much more versatile if
when in options when specifying external editor you coul
c:\editor.exe $file $linenum
and (for those editors that require a slash before line
c:\editor.exe $file /$linenum
For better compatibility with other editors this
feature would need some option in the GUI to specify
the editor specific command switch used to go to a line.
until this gets fixed up by someone I understand this
patch being delayed into the codebase.