replacement for readlink() function in windows

Question

readLink() is present in linux and is defined in unistd.h,is there any similar type function in windows please provide or else if we can make a function with similar functionality.I want to use the same functionality as readLink() please provide a user defined function for the replacement of the function in case no predefined function is there provided snap of the code

        char buffer[2048];

        readlink("/proc/self/exe", buffer, 2048);

        std::stringstream ss;
        ss << buffer;
        std::string exeFile = ss.str();
        std::string directory;

        const size_t last_slash_idx = exeFile.rfind('/');
        if (std::string::npos != last_slash_idx)
        {
            directory = exeFile.substr(0, last_slash_idx);
        }
        return directory;
    #endif 

Answer 1

Windows doesn't have a readlink(2) equivalent, but it does have a realpath(3) equivalent: GetFinalPathNameByHandleW().

See also: "How do I get information about the target of a symbolic link?" by Ramond Chen.

Pseudo-code is as follows, error checking omitted:

HANDLE hPath = CreateFileW(filename, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
DWORD len = GetFinalPathNameByHandleW(hPath, NULL, 0, FILE_NAME_OPENED);
WCHAR* realPathBuf = new WCHAR[len+1];
GetFinalPathNameByHandleW(hPath, realPathBuf, len, FILE_NAME_OPENED);

Note that realPathBuf may be a "local UNC" path, starting with \\?\.