Shared Lock method. How well does it perform when it comes to files?

Question

Shared Lock method. How well does it perform when it comes to files?

John 511

I am looking to use a shared lock method on a binary or text file.

I have learned that it is when share locking a file, the file is movable only afterwards.

Is that true?

If it is, then can any user provide me some source code snippet examples?

Regards,

John-1477

John 511

// Console App 00001.cpp : This file contains the 'main' function. Program execution begins and ends there.
//
#include <fstream>
#include <shared_mutex>
#include <mutex>
#include <string>

using namespace std;

int main()
{
    string FileNameX;
    FileNameX = "C:\\Users\\johnc\\Documents\\Track001.wav";
    ifstream output(FileNameX, ios::binary, ios::out);
    shared_lock<mutex>(FileNameX);

}

John 511 Reputation points

2021-06-20T07:48:39.713+00:00

The code snippet above enables users to provide a shared lock on the binary file.

However, it needs to be fixed. Users are welcome to update this above code snippet for me.

Regards,

John-1477
Jeanine Zhang-MSFT 11,356 Reputation points Microsoft External Staff

2021-06-21T02:43:11.387+00:00

@John

The <shared_mutex> header provides synchronization primitives for protection of shared data that can be accessed by multiple threads.

If you want to share locking a file, I suggest you could try to use LockFileEx function. The function locks the specified file for exclusive access by the calling process.