C ++：如何获取文件夹列表

Question

I am not familiar with C++ as I am a C# developer.

In my project, I need to delete all folders of one week before. In C++, how can I get the list of the folders of one week before based on the current system date time?

I am working on Eclipse IDE running on Ubuntu 10.10.

If you could provide some sample of code, that would be great.

Thanks in advance and your help is much appreciated!

Answer 1

It's more a question of your OS API than C++. C++ itself provides no facilities for filesystem operations. However, there are several portable libraries that do, boost::filesystem for example.

However, if you're stuck only to one operating system, it's easier to use it's facilities -- POSIX on *nixes, or WinAPI on Windows.

Both are C based, to get a C++ solution, you need a third party library.

On Linux, the following might get you started:

• File Access and Directory System Calls

Answer 2

With boost:

#include <boost/foreach.hpp>
#include <boost/filesystem.hpp>

int main(int, char**)
{
    time_t one_week_ago = std::time(NULL) - (7 * 24 * 3600);

    boost::filesystem::directory_iterator dir("/tmp"), end;

    BOOST_FOREACH(const boost::filesystem::path& p, std::make_pair(dir, end))
        if(boost::filesystem::is_directory(p))
            if(boost::filesystem::last_write_time(p) < one_week_ago)
                boost::filesystem::remove_all(p);
}

or without using boost::foreach

#include <boost/filesystem.hpp>

int main(int, char**)
{
    time_t one_week_ago = std::time(NULL) - (7 * 24 * 3600);

    boost::filesystem::directory_iterator dir("/tmp"), it, end;

    for(it = dir; it != end; it++)
    {
        const boost::filesystem::path& p = *it;
        if(boost::filesystem::is_directory(p))
            if(boost::filesystem::last_write_time(p) < one_week_ago)
                boost::filesystem::remove_all(p);
    }
}

Answer 3

I would have thought you should look at the functions opendir and readdir - also look at stat. Basically, open the top level directory, and examine all entries in it that are directories. The stat function will be able to give you access and modify times.