Yields the value True when the
task denoted by T is
callable, and False otherwise;
a
task is callable unless it is completed or abnormal. The value of this
attribute is of the predefined type Boolean.
Yields the value True if the
task denoted by T is terminated, and False otherwise. The value of this
attribute is of the predefined type Boolean.
For a
prefix
E that denotes an entry of a task or protected unit, the following attribute
is defined. This attribute is only allowed within the body of the task
or protected unit, but excluding, in the case of an entry of a task unit,
within any program unit that is, itself, inner to the body of the task
unit.
Yields the number of calls presently
queued on the entry E of the current instance of the unit. The value
of this attribute is of the type
universal_integer.
NOTE 2 {
AI12-0442-1}
Within task units, by interrogating the attribute E'Count an algorithm
can allow for the increase of the value of this attribute for incoming
entry calls, and its decrease, for example with
timed_entry_calls.
A
conditional_entry_call
can also briefly increase this value, even if the conditional call is
not accepted.
NOTE 3 {
AI12-0442-1}
Within protected units, by interrogating the attribute E'Count in the
entry_barrier
for the entry E an algorithm can allow for the evaluation of the
condition
of the barrier both before and after queuing a given caller.
Ada 2005 and 2012 Editions sponsored in part by Ada-Europe