this command sends GEN_FILE data of the file given in -remote_file. depending on the client, you might need to enter the destination file in -client_file.
-offset is the position in the file to start reading. it defaults to 0 if not given.
-len is the amount of data to read from the file. the host will auto fill it to the file size if not given. the host also auto fill to the file size if it larger than the actual file size.
-force bypasses any overwrite confirmation questions if the client does such a thing. the host does nothing with this. it's entirely up to the client to implement this option.