Para instalar o pidgin :
sudo apt-get install pidgin
Agora, o pacote pidgin-skype-common fornece principalmente dois arquivos de biblioteca compartilhada libskype_dbus.so e libskype.so para fazer interface do skype com o pidgin. Não tem nada com qualquer comando.
Você pode ver isso por dpkg -L pidgin-skype-common :
$ dpkg -L pidgin-skype-common
/.
/usr
/usr/lib
/usr/lib/purple-2
/usr/lib/purple-2/libskype_dbus.so
/usr/lib/purple-2/libskype.so
/usr/share
/usr/share/doc
/usr/share/doc/pidgin-skype-common
/usr/share/doc/pidgin-skype-common/README.Debian
/usr/share/doc/pidgin-skype-common/changelog.Debian.gz
/usr/share/doc/pidgin-skype-common/copyright
/usr/share/pidgin-skype-common
/usr/share/pidgin-skype-common/icons
/usr/share/pidgin-skype-common/icons/16
/usr/share/pidgin-skype-common/icons/16/skypeout.png
/usr/share/pidgin-skype-common/icons/16/skype.png
/usr/share/pidgin-skype-common/icons/22
/usr/share/pidgin-skype-common/icons/22/skypeout.png
/usr/share/pidgin-skype-common/icons/22/skype.png
/usr/share/pidgin-skype-common/icons/48
/usr/share/pidgin-skype-common/icons/48/skypeout.png
/usr/share/pidgin-skype-common/icons/48/skype.png
Além disso, se você executar dpkg -s pidgin-skype-common , poderá ver isso na seção Description :
Description: Skype plugin for libpurple messengers (common files)
This protocol plugin allows libpurple to communicate with Skype.
Applications using libpurple (Pidgin, Finch, Empathy/Telepathy,
etc.) can thus show your Skype contacts alongside those from
other protocols, and you can communicate with them using that
application instead of the Skype user interface.