dpkg --purge proftpd
(Reading database ... 22213 files and directories currently installed.)
Removing proftpd ...
/var/lib/dpkg/info/proftpd.postrm: line 5: /dev/tty: No such device or address
dpkg: error processing proftpd (--purge):
 subprocess post-removal script returned error exit status 1
Errors were encountered while processing:
 proftpd