sendport - Enable/disable port command

The sendport command defines whether or not FTP should call the PORT function in theremote host’s server at the start of a file transfer. If the PORT function is enabled, the sendport command disables it, and vice versa. On starting FTP, the PORT function is enabled.

Normally the PORT function must be implemented in each server. However, there are servers which do not behave in a standardized manner and which do not have the PORT function implemented. Such servers will respond to a PORT command with the errormessage:

550: Command not understood

or

502: PORT command not implemented

In this case, the PORT function must be disabled.

sendport