prerm is in talkd 0.17-15.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 | #!/bin/sh
set -e
if which update-inetd >/dev/null 2>&1; then
	update-inetd --pattern '[ \t]/usr/sbin/in\.talkd' --disable talk
	update-inetd --pattern '[ \t]/usr/sbin/in\.ntalkd' --disable ntalk
fi
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