File Glob in C++

Question

What's the C++ way of Perl's idiom:

my @files = glob("file*.txt");
foreach my $file (@files) {

   # process $file
}

Answer 1

The POSIX API specifies the glob() and globfree() functions for this. See the man page. wordexp() and wordfree(), also specified by POSIX, support other kinds of expansions as well.

Answer 2

There's no standard C++ way to emulate this because there is no standard C++ functionality of reading the contents of a directory. What you can do is use Boost.Filesystem:

#include <boost/filesystem.hpp> // plus iostream,algorithm,string,iterator
using namespace boost::filesystem; // and std

struct pathname_of {
    string operator()(const directory_entry& p) const {
        return p.path().filename(); // or your creativity here
    }
};

int main(int argc, char* argv[])
{
    transform(directory_iterator("."), directory_iterator(),
              ostream_iterator<string>(cout, "\n"),
              pathname_of());
    return 0;
}