std::ofstream, check if file exists before writing

Question

I am implementing file saving functionality within a Qt application using C++.

I am looking for a way to check to see if the selected file already exists be

Answer 1

One of the way would be to do stat() and check on errno.
A sample code would look look this:

#include 
using namespace std;
// some lines of code...

int fileExist(const string &filePath) {
    struct stat statBuff;
    if (stat(filePath.c_str(), &statBuff) < 0) {
        if (errno == ENOENT) return -ENOENT;
    }
    else
        // do stuff with file
}

This works irrespective of the stream. If you still prefer to check using ofstream just check using is_open().
Example:

ofstream fp.open("", ofstream::out);
if (!fp.is_open()) 
    return false;
else 
    // do stuff with file

Hope this helps. Thanks!