How to Prevent "svn diff" from Generating Unicode Output on Windows

On my Windows box, I tried to create a Subversion patch by using the comma开发者_JS百科nd svn diff > my_patch.diff. The resulting file was encoded with UTF-16, rather than UTF-8 or ASCII, so when I tried to use patch (from GnuWin32) to apply the patch, it didn't work.

I was able to convert the patch file to UTF8 by opening it in Notepad and saving as the desired format, and patch handled it fine after that. But, is there a way to get svn diff to generate UTF8 on Windows?

Update: As my answer indicates, it turns out that the problem is really unrelated to Subversion, diff, or patch. It was PowerShell that was oh-so-helpfully converting the output to Unicode. I'm leaving the question as-is so that someone with a similar problem might stumble upon it.

After much head-scratching and experimenting with different diff utilities, I figured this out:

I was running my svn diff in a PowerShell command window. PowerShell's output redirection operators convert the output to Unicode.

If I run svn diff > my_patch.diff in a cmd.exe shell, then everything works fine.

To make this work in PowerShell, one must use a command like this:

svn diff | out-file -encoding ascii my_patch.diff

I'm sure there is somebody at Microsoft who thinks this behavior is really awesome.