For years I have been able to suspend my Ubuntu-based machine from regular account using
dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend
This no longer works in Ubuntu 15.04, where the following is reported:
Error org.freedesktop.DBus.Error.UnknownMethod: Method "Suspend" with signature "" on interface "org.freedesktop.UPower" doesn't exist
One option to suspend without password prompt is to edit
sudoers and then
sudo pm-suspend. Are there any other ways that do not involve granting root privileges?