An ABOR request asks the server to stop any file transfer in progress. The client is permitted to send an ABOR request while waiting for a response to a file transfer request. However, the response to ABOR is still required to come after the response accepting or rejecting the file transfer request. The easiest way to abort the data transfer is to simply close the data connection. The client is permitted to send a STAT request while a file transfer is in progress.
Many servers accept asynchronous STATs.
The response text shows the number of bytes transferred so far, in some human-readable format. This response comes before the response to the file transfer request. Clients must not attempt to use this feature. Microsoft FTP Service 4.0 simply discards the STAT request, producing a disastrous loss of synchronization. Clients that want to know the progress of a file transfer can monitor the transfer locally.