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

`readlink` is specific to Linux. Are you using visual studio to build a linux application? If not, what do you expect `readlink` to do on Windows which doesn't have symlinks? — kaylum, Sep 30 '16 at 06:48
yes i am using visual studio the application is should be working for linux and windows as well — Ankit Srivastava, Sep 30 '16 at 06:51
That's not how things work. A binary built for Windows will not run in Linux (without other magic). — kaylum, Sep 30 '16 at 06:53
my application can detect the platform of machine and can work as accordingly without user input — Ankit Srivastava, Sep 30 '16 at 06:58
readlink is not applicable to Windows. You have to work out what you want the program to do in that case. — kaylum, Sep 30 '16 at 07:01
that is my point to post the question if there is any similar function in windows — Ankit Srivastava, Sep 30 '16 at 07:16
You are missing the point. Readlink and its function is not relevant for Windows. You need to work out what the linux version is doing with readlink and not just looking at readlink on its own. — kaylum, Sep 30 '16 at 07:23
@kaylum, nodejs supports this function on windows, so that's possible. — Qwertiy, May 03 '17 at 22:16

wheredidthatnamecomefrom · Answer 1 · 2018-09-14T17:04:51.913

Ok as stated in the comments Windows does not have a readlink() link api as such. That said the code given in the sample is doing something that really doesn't needed to handled directly by the program. Linux system api handles links for you. Also readlink does not null terminate it just returns raw data. That said QFile offers a platform independent api to resolve links. QFile::symLinkTarget provides a way to get the link target on both windows and unix without your program needing to mess with the OS specific side of this.

The windows process for doing this is not a one liner as it is on linux/unix systems. In fact there are actually two different types of links on windows. I highly recommend going through a framework such as Qt when trying to do cross platform I/O. Windows is a very different animal that your typical linux/unix system. For one thing it is not of POSIX system must linux/unix systems are.

score 0 · Answer 2 · answered Oct 31 '19 at 13:11

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 \\?\.

replacement for readlink() function in windows

2 Answers2