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launchd(8)                BSD System Manager's Manual               launchd(8)

     launchd -- System wide and per-user daemon/agent manager

     launchd [-d] [-D] [-s] [-S SessionType] [-- command [args ...]]

     launchd manages processes, both for the system as a whole and for individual users.  The primary and
     preferred interface to launchd is via the launchctl(1) tool which (among other options) allows the user
     or administrator to load and unload jobs.  Where possible, it is preferable for jobs to launch on
     demand based on criteria specified in their respective configuration files.

     During boot launchd is invoked by the kernel to run as the first process on the system and to further
     bootstrap the rest of the system.

     You cannot invoke launchd directly.

              This variable is exported when invoking a command via the launchd command line. It informs
              launchctl how to find the correct launchd to talk to.

     In Darwin, the canonical way to launch a daemon is through launchd as opposed to more traditional mech-anisms mechanisms
     anisms or mechanisms provided in earlier versions of Mac OS X. These alternate methods should be con-sidered considered
     sidered deprecated and not suitable for new projects.

     In the launchd lexicon, a "daemon" is, by definition, a system-wide service of which there is one
     instance for all clients. An "agent" is a service that runs on a per-user basis. Daemons should not
     attempt to display UI or interact directly with a user's login session. Any and all work that involves
     interacting with a user should be done through agents.

     If you wish your service to run as a certain user, in that user's environment, making it a launchd
     agent is the ONLY supported means of accomplishing this on Mac OS X. In other words, it is not suffi-cient sufficient
     cient to perform a setuid(2) to become a user in the truest sense on Mac OS X.

     ~/Library/LaunchAgents         Per-user agents provided by the user.
     /Library/LaunchAgents          Per-user agents provided by the administrator.
     /Library/LaunchDaemons         System-wide daemons provided by the administrator.
     /System/Library/LaunchAgents   Per-user agents provided by Mac OS X.
     /System/Library/LaunchDaemons  System-wide daemons provided by Mac OS X.

     launchctl(1), launchd.plist(5),

Darwin                            1 May, 2009                           Darwin

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