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macososx-lionlaunchd

What are the OS X session types, and what do they mean?

I've been trying to find out the meaning of LimitLoadToSessionType in launchctl on OS X (Lion).

After scouring the internet, it seems the value can be one of: Aqua, LoginWindow, Background, StandardIO and System.

Are there any missing, and more importantly, does anyone know what effect they have?

Solution

  • This Apple Technical Note explains most of the session types (it doesn't cover System; I think Tech Note was last updated for Snow Leopard and System was probably added for Lion):

    Briefly:

    • Aqua: a GUI agent; has access to all the GUI services
    • LoginWindow: pre-login agent; runs in the login window context
    • Background: runs in the parent context of the user
    • StandardIO: runs only in non-GUI login session (e.g. SSH sessions)

    I could guess about System, but then so could you. I wish Apple would update the TN2083 for OS X 10.7.