Hello everyone, I find it confusing that some inhibitions will prevent system from auto suspend, but not manually clicking suspend button, so I try to read source code of powerdevil and plasma-workspace.
As far as I can see, in plasma-workspace there is canSuspend function which will check systemd-inhibit from dbus, and return yes when login1 returns yes or challenge(some applications requests inhibition will lead to this). Suspend button uses this, but because canSuspend treats yes and challenge as the same, there is no difference whether systemd inhibition exists, that's why suspend button will ignore systemd inhibition. In powerdevil, what canSuspend returns is used in function loadAllInactiveActions, which will create a new profile with canSuspend and give it to suspendsession action, let it determine auto suspend or not. There is another mechanism which really works called policyagent. It syncs with systemd inhibitions and has its own inhibitions related to settings and old program(like ktorrent). When suspendsesstion handles timeout, it checks policyagent to determine whether to suspend or not. Now I wonder if these really work as expected? Do we need to check systemd inhibition and give a warnning before do actual suspend work when inhibition exists?
