git graphical diff

One can use the "git difftool" command, which has direct knowledge of many diffing tools, including meld.
By default it always asks for which diffing tool to use (and defaults to 'meld' on my box), but you can automate the choice with configuration variables. See "git help difftool" for details.

Src: http://blog.deadlypenguin.com/blog/2011/05/03/using-meld-with-git-diff/
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