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copied!<p>I'd tackle this problem this way: There are 3 alternatives for copying a file:</p> <ol> <li>On Unix, you can use <a href="http://docs.python.org/library/os.html#os.link" rel="nofollow"><code>os.link</code></a>.</li> <li><p>On Windows, you can use a function like this:</p> <pre><code>def CreateHardLink(src, dst): import ctypes if not ctypes.windll.kernel32.CreateHardLinkA(dst, src, 0): raise OSError </code></pre> <p>(Disclaimer: I haven't tested it. The idea is to use the kernel32 API.)</p></li> <li>If all this fails, you can still make a regular file copy (for example, with <code>shutil.copy2</code>).</li> </ol> <p>Then, you can test these 3 functions at the beginning of the script with a temporary file (to be deleted afterwards). The first of these 3 functions that succeeds (that is, the first one that raises no <code>Exception</code>) is a good candidate for making the actual backup copies.</p> <p>This idea follows a <a href="http://en.wikipedia.org/wiki/Strategy_pattern" rel="nofollow">strategy pattern</a>, where you have to select a function that takes the source and destination filenames and makes the best effort to make the copy the way you want it.</p> <p>Let me add one more thing: Detecting the filesystem in order to choose a copying strategy is not a very good practice in the same way that detecting browsers is not a good practice to do different things in Javascript. It's always best to try to use a feature and be prepared to catch exceptions or handle errors in order to produce an alternative result.</p>

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