subscribe and unsubscribe

$session->subscribe( $C, $I, $E [, $flags ] );
$session->subscribe( "$C::$I::$E[/$flags]" );
$session->unsubscribe( $C, $I, $E [, $flags ] );
$session->unsubscribe( "$C::$I::$E[/$flags]" );

These functions subscribe, or unsubscribe, to notifications of the specified events. “$C”, “$I”, “$E” must be regexp patterns that represent the classes, instances, and events to which to subscribe.

The unsubscribe() function is the inverse of subscribe().

The $flags value is a bitwise combination of the values or a more mnemonic string as shown in Subscription flag parameter values

Table 1. Subscription flag parameter values

Flag bitfield value	Description
0x000001	Simple event
0x000002	Simple aggregation
0x000010	Problem
0x000020	Imported event
0x000040	Propagated aggregation
0x0000ff	All
0x001000	Expand subclasses
0x002000	Expand subclasses events
0x004000	Expand aggregations
0x008000	Expand closures
0x010000	Sticky
0x020000	Undo all
0x040000	Quiet accept
0x080000	Quiet suspend
0x100000	Glob

As a compatibility aid, the $flag can also be specified as a string of letters. In this case, each of the letters are subscription qualifiers:

• “p” means subscribe to problems

• “a” means subscribe to aggregates (impacts)

• “e” means subscribe to events.

  Note:

  If “p”, “a” or “e” are not present, “p” is assumed.

• “v” means run in verbose mode, which turns on subscription control messages.

  The action of these options is the same as that provided by the sm_adapter program’s --subscribe= option.

  Examples:

   $session->subscribe( "Router", ".*", ".*", "/pev" );
   $session->subscribe( "Router::.*::.*/peav" );
   $session->subscribe( $obj, ".*", 0x3 );
   $session->unsubscribe( $obj, ".*", 0x3 );