+ This function associates a match specification with trace event
+ send or 'receive'. By default all executed send
+ and 'receive' events are traced if enabled for a process.
+ A match specification can be used to filter traced events
+ based on sender, receiver and/or message content.
+ For a description of the match_spec() syntax,
+ please turn to the User's guide part of the online
+ documentation for the runtime system (erts). The
+ chapter Match Specifications in Erlang
+ explains the general match specification "language".
+ For send, the matching is done on the list [Receiver, Msg].
+ Receiver is the process or port identity of the receiver and
+ Msg is the message term. The pid of the sending process can be
+ accessed with the guard function self/0.
+ For 'receive', the matching is done on the list [Node, Sender, Msg].
+ Node is the node name of the sender. Sender is the
+ process or port identity of the sender, or the atom
+ undefined if the sender is not known (which may
+ be the case for remote senders). Msg is the
+ message term. The pid of the receiving process can be
+ accessed with the guard function self/0.
+ All nodes added with n/1 or
+ tracer/3 will
+ be affected by this call.
+ The return value is the same as for
+ tp/2. The number of matched
+ events are never larger than 1 as tpe/2 does not
+ accept any form of wildcards for argument Event.
+
+