今天很偶然的在cppblog上看了个博客，提到这个API，然后我想起来之前很困惑的一个问题。为什么别人的程序.exe和.dll是放在不同目录的，而我的不能。起初我想的是也许只能用添加path这一招了。今天偶然看到这个函数顺便msdn一下发现还是挺有用的。以后俺们的dll和exe也不用恶心的都丢到一起了，可以根据模块和功能放到不同的目录了。
SetDllDirectory function
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Applies to: desktop apps only
Adds a directory to the search path used to locate DLLs for the application.
Syntax
C++
BOOL WINAPI SetDllDirectory(
__in_opt LPCTSTR lpPathName
);
Parameters
- lpPathName [in, optional]
-
The directory to be added to the search path. If this parameter is an empty string (""), the call removes the current directory from the default DLL search order. If this parameter is NULL, the function restores the default search order.
Return value
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
Remarks
The SetDllDirectory function affects all subsequent calls to the LoadLibrary and LoadLibraryEx functions. It also effectively disables safe DLL search mode while the specified directory is in the search path.
After calling SetDllDirectory, the standard DLL search path is:
- The directory from which the application loaded.
- The directory specified by the lpPathName parameter.
- The system directory. Use the GetSystemDirectory function to get the path of this directory. The name of this directory is System32.
- The 16-bit system directory. There is no function that obtains the path of this directory, but it is searched. The name of this directory is System.
- The Windows directory. Use the GetWindowsDirectory function to get the path of this directory.
- The directories that are listed in the PATH environment variable.
Each time the SetDllDirectory function is called, it replaces the directory specified in the previous SetDllDirectory call. To specify more than one directory, use theAddDllDirectory function and call LoadLibraryEx with LOAD_LIBRARY_SEARCH_USER_DIRS.
To revert to the standard search path used by LoadLibrary and LoadLibraryEx, call SetDllDirectory with NULL. This also restores safe DLL search mode based on theSafeDllSearchMode registry value.
To compile an application that uses this function, define _WIN32_WINNT as 0x0502 or later. For more information, see Using the Windows Headers.