liuxg@liuxg:~/Downloads$ sudo dpkg -i skypeforlinux-64-alpha.deb
Selecting previously unselected package skypeforlinux.
(Reading database ... 351928 files and directories currently installed.)
Preparing to unpack skypeforlinux-64-alpha.deb ...
Unpacking skypeforlinux (1.12.0.4) ...
Setting up skypeforlinux (1.12.0.4) ...
Processing triggers for bamfdaemon (0.5.3~bzr0+16.04.20160824-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for gnome-menus (3.13.3-6ubuntu3.1) ...
Processing triggers for desktop-file-utils (0.22-1ubuntu5) ...
Processing triggers for mime-support (3.59ubuntu1) ...
Processing triggers for hicolor-icon-theme (0.15-0ubuntu1) ...