# Windows Git will not start external diff at all

2 messages from 2016-09-06 to 2016-09-06. Participants: Jaakko Pääkkönen, Johannes Schindelin.
Thread: https://gitlist.dev/t/44021

## Jaakko Pääkkönen, 2016-09-06 15:57

Subject: Windows Git will not start external diff at all
Message-ID: <CADr93XDA3CdgGBqBJTdmCHg_ZzGhsBf5hwwORJaCNB-V7o+APg@mail.gmail.com>
URL: https://gitlist.dev/e/CADr93XDA3CdgGBqBJTdmCHg_ZzGhsBf5hwwORJaCNB-V7o%2BAPg%40mail.gmail.com

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Hi

I am using beyond compare, but it does not really matter which one
because even I create a dummy script as a external diff program, it
will not get called ever. Only internal diff is started.

Re-installing git will not remove the problem. I am using the latest git

Any hints how I can debug git difftool?

--jaakko

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## Johannes Schindelin, 2016-09-06 16:34

Subject: Re: Windows Git will not start external diff at all
Message-ID: <alpine.DEB.2.20.1609061832380.129229@virtualbox>
URL: https://gitlist.dev/e/alpine.DEB.2.20.1609061832380.129229%40virtualbox
In-Reply-To: <CADr93XDA3CdgGBqBJTdmCHg_ZzGhsBf5hwwORJaCNB-V7o+APg@mail.gmail.com>

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Hi Jaakko,

On Tue, 6 Sep 2016, Jaakko Pääkkönen wrote:

> I am using beyond compare, but it does not really matter which one
> because even I create a dummy script as a external diff program, it
> will not get called ever. Only internal diff is started.

Any chance you can come up with an MCVE [*1*] using a dummy script?

> 
> Re-installing git will not remove the problem. I am using the latest git
> 
> Any hints how I can debug git difftool?

Sure. First hint: set GIT_TRACE=1. Next hint: difftool is a shell script,
so you can modify it, say, by inserting a `set -x` which will trace the
commands that are called.

Ciao,
Johannes

Footnote *1*: http://stackoverflow.com/help/mcve
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