c++dll

How does the linker know where to find a dll file

I am working with Visual Studio and I am trying to get into dlls. I'm wondering how the linker knows where to find a DLL just from the lib file alone. I specify the lib file and its location in the project settings but where isthe location of the associated dll file specified? Or maybe i don't understand the topic correctly.

Solution

  • The Standard Search Order for Desktop Applications from the Microsoft Dll Search Order documentation:

    If SafeDllSearchMode is enabled, the search order is as follows:

    1. The directory from which the application loaded.
    2. The system directory. Use the GetSystemDirectory function to get the path of this directory.
    3. The 16-bit system directory. There is no function that obtains the path of this directory, but it is searched.
    4. The Windows directory. Use the GetWindowsDirectory function to get the path of this directory.
    5. The current directory.
    6. The directories that are listed in the PATH environment variable. Note that this does not include the per-application path specified by the App Paths registry key. The App Paths key is not used when computing the DLL search path.

    If SafeDllSearchMode is disabled, the search order is as follows:

    1. The directory from which the application loaded.
    2. The current directory.
    3. The system directory. Use the GetSystemDirectory function to get the path of this directory.
    4. The 16-bit system directory. There is no function that obtains the path of this directory, but it is searched.
    5. The Windows directory. Use the GetWindowsDirectory function to get the path of this directory.
    6. The directories that are listed in the PATH environment variable. Note that this does not include the per-application path specified by the App Paths registry key. The App Paths key is not used when computing the DLL search path.