This way should cover all un*x-like OSes (unopkg.sh excludes
e.g. OS X)
This effectively reverts commits 723e0999 and
9444ffc9

Change-Id: I0b4425d1c9eff8e51e5d9a4dab35775084106a23
(cherry picked from commit faa2c06226146e3ab4b7fa8096cf213ea9d52a23)