See (annalist) for something
that has been implemented in this area.
Let EMC be the entry monitor creator.
EMC(0;SB,M,N ==> c;ME) "Create Entry Monitor"
Where N is a node or fetch key to a node containing:
EMC(kt;==>c;) returns loose end in c.
ME is a monitored entry key. Whenever ME is called,
the call is recorded by a call of the form MB(order code,(byte
string passed to ME); ==> ;). Then the call is passed
on to key E.
Keys are not recorded. Returns from E are not recorded.
MB can be a multiplexor branch key.
C is loose end.