On Thu, Dec 2, 2010 at 12:23 PM, Graham Leggett <minf...@sharp.fm> wrote: > On 23 Nov 2010, at 8:21 PM, Dan Poirier wrote: > >> We're seeing errors like this from mod_disk_cache on Windows only: >> >> (OS 5)Access is denied. : disk_cache: rename tempfile to datafile >> failed: c:/temp/HTTPServer7/aptmpV0JKJ8 -> >> c:/temp/HTTPServer7/wHY/FhW/b...@muvttlk@V4w.data >> >> under moderate to heavy load, resulting in requests failing. > > Looking at the code, the error message is thrown when apr_file_rename() > fails, specifically when a temporary file is swung into place in the cache. > > Looking at the APR code, there is a forest of ifdefs that seem to choose one > of MoveFileEx(), MoveFileW(), MoveFileExW() or MoveFile(). Ideally, the > Microsoft API documentation should explain under what conditions the error > "Access is denied" is thrown. > > Does Windows allow you to move a file into place while the replaced file is > still open for read?
Disclaimer: My last real Windows programming was on WfW 3.11, so please, someone with up-to-date Windows programming experience correct me as needed. >From the doc for MoveFileEx (http://msdn.microsoft.com/en-us/library/aa365240%28VS.85%29.aspx), you can pass a flag telling Windows to do the move on the next reboot (also see http://support.microsoft.com/kb/140570) , apparently to work around an inability to rename another file over a file in use. So I think the answer to your question is "no". The doc for error 0x05 at http://msdn.microsoft.com/en-us/library/ms681382%28v=VS.85%29.aspx consists, in its entirety, of "Access is denied.". Maybe there's more explanation elsewhere. -- Dan Poirier <poir...@pobox.com>
