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delphiwinapitfilestream

How to use TFileStream with FILE_SHARE_DELETE?

This QC report say that Delphi doesn't support the file sharing mode FILE_SHARE_DELETE

http://qc.embarcadero.com/wc/qcmain.aspx?d=45628

I need to use this mode with TFileStreams - Can anyone think of a straightforward workaround that doesn't involve modifying the library code, or duplicating reams of stuff from the library?

Solution

  • The QC report is correct. TFileStream (more specifically, the SysUtils.FileOpen() function) does not support FILE_SHARE_DELETE. It only supports FILE_SHARE_READ and FILE_SHARE_WRITE.

    In order to use sharing rights beyond what TFileStream natively supports, you will have to call the Win32 API CreateFile() function directly, then you can construct a THandleStream object using the handle that CreateFile() returns.