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  1. #1
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    is there a faster alterantive for CreateFileW ?

    I'm writing a directory enumerator and CreateFileW takes as long as NtQueryDirectoryFile when it's cached , is there a faster alternative to get the handle ?

  2. #2
    2kaud's Avatar
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    Re: is there a faster alterantive for CreateFileW ?

    CreateFile() is the basic WIN32 user mode for function for creating/opening a file.

    For a directory enumerator, why do you need to get the handle for each file? To enumerate a directory, use FindFirstFileEx() and then FindNextFile(). See https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx and https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx and for an example of use https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx
    All advice is offered in good faith only. All my code is tested (unless stated explicitly otherwise) with the latest version of Microsoft Visual Studio (using the supported features of the latest standard) and is offered as examples only - not as production quality. I cannot offer advice regarding any other c/c++ compiler/IDE or incompatibilities with VS. You are ultimately responsible for the effects of your programs and the integrity of the machines they run on. Anything I post, code snippets, advice, etc is licensed as Public Domain https://creativecommons.org/publicdomain/zero/1.0/ and can be used without reference or acknowledgement. Also note that I only provide advice and guidance via the forums - and not via private messages!

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  3. #3
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    Re: is there a faster alterantive for CreateFileW ?

    Quote Originally Posted by 2kaud View Post
    CreateFile() is the basic WIN32 user mode for function for creating/opening a file.

    For a directory enumerator, why do you need to get the handle for each file? To enumerate a directory, use FindFirstFileEx() and then FindNextFile(). See [url]https://msdn.microsoft.com/en
    I need a handle for each directory to use with the NtQueryDirectoryFile
    Last edited by 2kaud; May 11th, 2017 at 01:51 AM.

  4. #4
    2kaud's Avatar
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    Re: is there a faster alterantive for CreateFileW ?

    NtQueryDirectoryFile() is a driver function. If you are writing a driver, the driver function to open a file is NtOpenFile(). See https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx
    All advice is offered in good faith only. All my code is tested (unless stated explicitly otherwise) with the latest version of Microsoft Visual Studio (using the supported features of the latest standard) and is offered as examples only - not as production quality. I cannot offer advice regarding any other c/c++ compiler/IDE or incompatibilities with VS. You are ultimately responsible for the effects of your programs and the integrity of the machines they run on. Anything I post, code snippets, advice, etc is licensed as Public Domain https://creativecommons.org/publicdomain/zero/1.0/ and can be used without reference or acknowledgement. Also note that I only provide advice and guidance via the forums - and not via private messages!

    C++23 Compiler: Microsoft VS2022 (17.6.5)

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