You probably have the Gnu diff for Windows? Try diff --version.

Your diff returns exit code 1 (not 256 - you need to look at the "upper" byte), which typically means that the files are different. Nothing unusual here.
-- 
Ronald Fischer <ynnor@mm.st>

In reply to Re: [Win32] Successful system() call returns 256 by rovf
in thread [Win32] Successful system() call returns 256 by syphilis

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