# subroutine name: list_dir
# Input: 	absolute path to directory 
#			files filter regexp [if empty, filter is ignored]
#			minumal age (in days since last modification time) [if empty, 
#                         filter is ignored]
# Returns: array of found files (path included in filename)
sub list_dir {
	my ($dir, $regexp, $min_age) = @_;
	my @passed;
	if (opendir (LISTDIR, $dir)) {
		my @files = readdir(LISTDIR);			# Read in list of files in directory..
		closedir (LISTDIR);
		foreach my $file (@files) {
			if ($file ne "." && $file ne ".." && -f "$dir/$file" && ($regexp eq "" || $file =~ m/$regexp/s)) {
				if ($min_age) {
					push (@passed, "$dir/$file") if (-M "$dir/$file" > $min_age);
				} else {
					push (@passed, "$dir/$file");
				}
			}
		}
	}
	return @passed;
}