Install libadns1-dbg by entering the following commands in the terminal:
sudo apt update sudo apt install libadns1-dbg
Description:
Asynchronous-capable DNS client library (debugging symbols)
adns is a resolver library for C (and C++) programs. In contrast with the existing interfaces, gethostbyname et al and libresolv, it can be used in an asynchronous, non-blocking manner, and has a convenient interface which doesn't require the application to handle any DNS data formats. Many queries can be handled simultaneously. . This package contains the debugging symbols associated with libadns1, for debugging adns and programs that use it.
Homepage: http://www.chiark.greenend.org.uk/~ian/adns/
Version: 1.5.0~rc1-1.1ubuntu1
Section: universe/debug