I'll add another contender here, codeblocks http://www.codeblocks.org/
have a look at at the features page.
it does split a window for any file, but no multiple buffers of the same
file.
But for anyone looking/choosing editors its worth a second glance.
Handy if you do work for/on different targets.
It will frun from an Xwindow under Win, I use Xming.
btw it's freeware as GPL v3.0 spec.


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