Urs Thuermann <urs@isnogud.escape.de> writes:

> I sometimes get into the following situation:  I open a file, make
> some changes, then I want to see the changes before saving the file.
> The best way to do this seems to be to set the region to the whole
> buffer, write the region to some temporary file, and run diff on the
> two files.  But I find this very unconvenient.
>
> I'd like to have a function in emacs which can be applied to a buffer,
> say buffer A, that opens a new buffer displaying all the changes
> between the buffer A and the disk file, opened in buffer A.

I think what you want is 
M-x diff-buffer-with-file RET RET

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 |      Michaël `Micha' Cadilhac   |  Would someone please DTRT with this,  |
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