PHP FTP Send File: Send or resume uploading files to a FTP server

This class can send or resume uploading files to a FTP server.

It can open a remote file for writing given a stream URL. The file is overwritten if already exists.

The class uploads the contents of a local file to the remote server file.

It writes a block of data at a time and if it fails writing to the remote file, it retries up to a given number of attempts appending data to the remote file from the point it stopped.

The class verifies the integrity of the upload by comparing the MD5 hash of the local file with the MD5 hash of the file sent to the server.

What is the best PHP FTP file upload class?
Send files to a secure FTP site