notifyutil(1)						    BSD General Commands Manual 					     notifyutil(1)

NAME

     notifyutil -- notification command line utility

SYNOPSIS

     notifyutil [-q] [-v] [-z msec] [-M] [-R] [command ...]

DESCRIPTION

     notifyutil is a command-line utility for interacting with the notify(3) notification system and the notifyd(8) server.  It may be used to
     post notifications, detect and report notifications, and to examine and set the state values associated with notification keys.

     If notifyutil is used to monitor one or more notification keys, it prints the notification key when the corresponding notification is
     received.	The -v (verbose) and -q (quiet) flags, if specified, modify the output behavior.

     The -v flag causes notifyutil to print a time stamp, the notification key, the current state value for that key, and the type of the notifi-
     cation (port, file, etc).	The -q flag supresses any output except for state values fetched following a -g command.

     Commands listed in the table below are processed in left to right order from the command line.

	   -p key	Post a notification for key.
	   -w key	Register for key and wait forever for notifications.
	   -# key	Register for key and wait for # (an integer) notifications.
			E.g. -1 key waits for a single notification.
	   -g key	Get state value for key.
	   -s key val	Set state value for key.
	   -port	Use mach port notifications for subsequent -w or -# registrations.
			This is the default registration type.
	   -file	Use file descriptor notifications for subsequent registrations.
	   -check	Use shared memory notifications for subsequent registrations.
	   -signal [#]	Use signal notifications for subsequent registrations.
			Signal 1 (HUP) is the default, but an alternate signal may be specified.
	   -dispatch	Use dispatch for subsequent registrations.

     When invoked with any combination of -w and -# actions, notifyutil registers for notification for the specified key(s).  If any key is given
     with a -w action, notifyutil runs until interrupted with Control-C.  If all registrations are invoked with -#, the program continues to run
     until the corresponding number of notifications for each key have been received.

     By default, notifyutil uses mach port registration (using notify_register_mach_port()) for keys given with a -w or -# flag.  The -file com-
     mand causes notifyutil to use notify_register_file_descriptor() for any subsequent -w or -# registrations.  Similarly, -check causes
     notifyutil to use notify_register_check() for subsequent registrations, -signal switches to notify_register_signal(), and -dispatch causes it
     to use notify_register_dispatch() for subsequent registrations.

     If any registrations are made following the use of the -check command, notifyutil will start a timer and check for shared memory notifica-
     tions every 100 milliseconds.  An alternate timer value may be set following the -z flag.

     The -M flag causes notifyutil to use multiplex all notifications over a single mach connection with notifyd.  Notifications (except shared
     memory notifications) are received and redistributed by a dispatch handler.

     The -R flag causes notifyutil to regenerate all its registrations in the unlikely event that notifyd restarts.

     Note that a notification key and its associated state variable only exist when there are one or more current registrations for that key.
     Setting the state for a key that has no registrations has no effect.  Thus the command

	   notifyutil -s foo.bar 123 -g foo.bar

     will print

	   foo.bar 0

     unless foo.bar is registered by some other process.  However, the command

	   notifyutil -w foo.bar -s foo.bar 123 -g foo.bar

     prints

	   foo.bar 123

     since the ``-w foo.bar'' registration ensures the key and its state variable exist before the value is set, and continue to exist when the
     value is fetched.

SEE ALSO

     notify(3), notifyd(8)

Mac OS X							 November 4, 2011							  Mac OS X