What does voidresp() in ftplib do?

[William Umboh]

Hi all,
I am doing an FTP app and need to download only segments of a file. To
do this, I rewrote parts of the retrbinary() method in a subclass of
the FTP object and , since I need to enable the object to realise when
it has downloaded the segment required. However, the voidresp() at the
end of the original retrbinary() method raised an exception that said
'Transfer aborted. Broken pipe.' I am not sure about the second
sentence but aborting the transfer was my intention.
So, should I just leave out voidresp() or catch the exception, and do
nothing if the error code returned is the above and reraise if not?
What is the use of voidresp() at the end of the method retrbinary
anyway?
Thanks in advance.