I need to source a file upload script that can connect to a third-party ftp server. I've been looking at php-based apps, but all of them are designed to upload the file to a directory on the same server where the script is hosted.
Also, I'm looking for a simple file upload interface not a full, php ftp client. Basically I only want site visitors to upload files, not be able to browse a directory structure or see any other files that have been uploaded.
if you are using one server to upload to another then you are going to have to upload to the first server and then push it to the other server. If you don't fully control the other server then you are looking at ftp functions which means you probably will have close to a full blown ftp client.
The logic of what you are trying to do makes standard upload scripts useless and full ftp clients overkill. You should probably rethink your logic a bit, you will probably need to adjust what you are trying to do or at least step it out to do it differently.