C++ How to check the last modified time of a file

Question

I\'m caching some information from a file and I want to be able to check periodically if the file\'s content has been modified so that I can read the file again to get the new c

Answer 1

There is no language-specific way to do this, however the OS provides the required functionality. In a unix system, the stat function is what you need. There is an equivalent _stat function provided for windows under Visual Studio.

So here is code that would work for both:

#include 
#include 
#ifndef WIN32
#include 
#endif

#ifdef WIN32
#define stat _stat
#endif

auto filename = "/path/to/file";
struct stat result;
if(stat(filename.c_str(), &result)==0)
{
    auto mod_time = result.st_mtime;
    ...
}