Version:            (using Devel)
OS:                Linux
Installed from:    Compiled sources

I have some thoughts taken from negative experience of several simultaneous DE logins with KDE3. I don't know whether KDE4 developers are aware of those, but anyway:

-- KDE4 proper session management --

o. any webcam(s) should be released by decibel/phonon and IM app (kopete, etc.). If one was active during screen lock/session switch, IM app should broadcast still image 'user left computer' to all active videochat opponents instead of captured picture. Webcam(s) should be automatically accessed by active session only (security issue).
o. any video player should pause if playing videostream on session being locked/abandoned.
o. any audio player should put option 'pause/resume play' on relevant session's lock screen (like keyboard switcher is available next to password input field). Unlock password input dialog should be flexible enough to handle several 'pause/resume play' widgets. COMMENT: one user can activate playback of mp3/ogg via amarok AND audioCD with kscd. We need to handle all of them.
o. kmix should preserve volume and other settings in newly opened session, settings taken from the first session. Changing params should reflect in all opened sessions.
o. TV app should behave like any audio player as described above. COMMENT: user might want to listen to the TV news while screen is locked/session is inactive.
o. knetworkmanager (KNM hereinafter) should preserve connection made from first session on any other sessions and display relevant dock icon on active session, same as in first one. User on active session should be able to re-connet to any other network/profile though. In this case KNM should inform other locked/inactive sessions of net configuration changes.
o. if any kppp connection is active, any other consequent sessions should display kppp's systray icon showing actual status of it, with ability to drop connection by entering root pass (or pass of user that ran kppp first).
o. KNM's VPN settings should have choice whether to terminate or remain active VPN sessions on session switch (security issue). If set to 'terminate upon session switch', KNM should issue relevant popup for user that started VPN.
o. KDE bluetooth support should show activity systray icons reflecting current transfer states of other sessions, if ones where started before session switch and are still in progress. kbluetooth (as well as KNM) should display any popups/info in active session.
o. external mass storage, like SD/MMC/USB/... (EMS hereinafter) - i/o should continue normally on locked/abandoned session (like what we have now). Active session's filemanagers should display current state of connected/mounted EMS device (mounted/not mounted/etc.)

'Take over...' abilities:
o. 'take over...' (hereinafter as TO) - ability to gain access to device in use by locked/inactive session. Should require to enter root password for e.g. unmount/remount purposes (security issue as well).
o. webcam(s) should be released by locked session and ready/accessible directly from within current active session.
o. optical drive access app (kscd, k3b, konq, etc.) should detect whether other session is using the drive and offer TO action for current active user except several cases:
  a) optical burning app (k3b, konq) is burning media on any locked session - issue warning 'unable to TO due to burning in progress'.
  b) copying from media is in progress on any locked session. In this case TO event may offer 'take over when device activity ends' option (e.g. when copying is finished).
o. EMS devices may be TO'ed by active session's filemanager just like optical drives b) scenario.
o. tv/dvb-tuner may be TO'ed
o. any app dealing with TO-enabled device should correctly handle TO events on locked/inactive sessions; if e.g. active tv-tuner on session A was TO'ed by session B, TV app on session A should suspend activity and display popup "TO'ed by user B on session B" or thelike. This is feedback for user on session A (to prevent bugreports like 'my tv app stopped suddenly a while after I locked session' :) )


potentially shared devices list:
o. network card
o. any modem
o. audio card
o. bluetooth
o. webcam
o. tv/dvb-tuner
o. cardbus/xpresscard device
o. external mass storage devices (except net-mounted, like nfs/smb/etc.)
o. optical drive
o. scanner ???

affected apps list:
o. amarok
o. kdetv
o. k3b
o. kscd
o. kmplayer/kplayer/kaffeine
o. kbluetooth
o. knetworkmanager
o. kppp
o. kopete
o. dolphin
o. konqueror
o. any 'file open/save' dialog from any app
o. kmix
o. kooka

Please post your comments/thoughts.