GNU networking utilities
2.3 Aborting A File Transfer
To abort a file transfer, use the terminal interrupt key (usually Ctrl-C).
Sending transfers will be immediately halted. Receiving transfers
will be halted by sending a ftp protocol ABOR command to the remote server,
and discarding any further data received. The speed at which this is
accomplished depends upon the remote server's support for ABOR processing.
If the remote server does not support the ABOR command, an `ftp>'
prompt will not appear until the remote server has completed sending the
The terminal interrupt key sequence will be ignored when ftp has completed
any local processing and is awaiting a reply from the remote server.
A long delay in this mode may result from the ABOR processing described
above, or from unexpected behavior by the remote server, including violations
of the ftp protocol. If the delay results from unexpected remote
server behavior, the local ftp program must be killed by hand.