Net::FTP::Recursive 递归FTP调用

语法：

    use Net::FTP::Recursive;

    $ftp = Net::FTP::Recursive->new("some.host.name", Debug => 0);
    $ftp->login("anonymous",'me@here.there');
    $ftp->cwd('/pub');
    $ftp->rget( ParseSub => \&yoursub );
    $ftp->quit;

说明：

默认缺省采用 UNIX-style directory listings 列表方式处理。如果ftp是其他方式的列表，要自己提供方法解析数据，返回一个 Net::FTP::Recursive::File objects 列表。
当Debug 设置为1，ftp将打印命令到STDERR。
所以方法如果执行成功返回 false ‘’，true值为失败。

构造函数：

new (HOST [,OPTIONS])
参照Net::FTP  的new 方法。

方法：

rget ( [ParseSub =>\&yoursub] [,FlattenTree => 1] [,RemoveRemoteFiles => 1] )

rput ( [FlattenTree => 1] [,RemoveLocalFiles => 1] )

rdir ( Filehandle => $fh [, FilenameOnly => 1 [, PrintType => 1] ] [, ParseSub => \&yoursub ] )

rdelete ( [ ParseSub => \&yoursub ] )

Net::FTP::Recursive::File 辅助类

# Parsing subroutine for Windows
# - may also be used as an example for your own FTP server if your output
#   isn't parsing correctly


sub parse_sub{

    my(@to_return) = ();

    foreach my $line (@_) {

        my($file); #reinitialize var

        next unless my @fields =
          $line =~ /^
                     (\S+)\s+ #date
                     (\S+)\s+ #time
                     (<DIR>)?\s* #user owner %u
                     (\d+)\s+ #size %s
                     (.+?)\s* #filename %f
                     (?:->\s*(.+))? #optional link part %l
                    $
                   /x;


        @fields = ( $fields[2], undef, undef, undef, $fields[3],
                    "$fields[0]$fields[1]", @fields[4,5] );

        my($perms) = ($fields[0]);

        next if $fields[6] =~ /^\.{1,2}$/;

        if ($perms =~ /<DIR>/){
            $file = Net::FTP::Recursive::File->new(IsPlainFile => 0,
                                                   IsDirectory => 1,
                                                   IsSymlink   => 0,
                                                   OriginalLine => $line,
                                                   Fields => [@fields]);
        }
        else {
            $file = Net::FTP::Recursive::File->new(IsDirectory => 0,
                                                   IsPlainFile => 1,
                                                   IsSymlink   => 0,
                                                   OriginalLine => $line,
                                                   Fields => [@fields]);
        }

        push(@to_return, $file);
    }

    return(@to_return);
}

# linux 方式的ftp命令解析
 $line =~ /^([a-z-])([a-z-]{9})  # -rw-r--r--
                      \s+(\d*)                # 1
                      (?:\s+(\w+))(?:\s+(\w+))         # root root
                      \s+(\d+)                # 312
                      \s+(\w+\s+\d+\s+[\d:]+) # Aug 1 1994
                       \s+(.+)               # welcome.msg
    
                 $/x;