title: How do I apply a diff patch on Windows?
body: <p>There are plenty of programs out there that can create a diff patch, but I'm having a heck of a time trying to apply one. I'm trying to distribute a patch, and I got a question from a user about how to apply it. So I tried to figure it out on my own and found out that I have no clue, and most of the tools I can find are command-line. (I can handle a command line, but a lot of people would be lost without a nice, friendly GUI. So those are no good for this purpose.)</p>
  
  <p>I tried using TortoiseSVN. I have the patch I'd like to apply. I right-click on the patch, and there's an option under the TortoiseSVN submenu that says "Apply patch." All it does is pull up an empty window.</p>
  
  <p>So I tried hitting Open. It has two options: merge and apply unified diff. (The patch is in unified diff format, luckily.) But the apply option just plain doesn't work: It asks for the patch and a folder. Somehow it forgot to ask for the <em>file to apply the patch to!</em> So TortoiseSVN just plain doesn't work. Is there a Windows GUI-based utility that will take a patch and a file and apply it properly?</p>
  
  <p>EDIT: Looking at the replies so far, it seems that Tortoise will only do it right if it's a file that's already versioned. That's not the case here. I need to be able to apply a patch to a file that did not come out of an SVN repository. I just tried using Tortoise, because I happen to know that SVN uses diffs and has to know how to both create them and apply them.</p>