T-Kernel Specification (1.B0.02)

4.5. EXTENDED SYNCHRONIZATION AND COMMUNICATION FUNCTIONS 137
The capability of setting rendezvous conditions in calptn and acpptn can be applied to implement a
rendezvous selective acceptance function like the ADA select function. A specific processing approach
equivalent to an ADA select statement (Figure 4.6) is shown in Figure 4.7.
The ADA select function is provided only on the accepting end, but it is also possible to implement a
select function on the calling end by designating multiple bits in calptn.
[Rationale for the Specification]
The reason for specifying separate system calls tk cal por and tk acp por even though the conditions
for establishing a rendezvous mirror each other on the calling and accepting sides is because processing
required after a rendezvous is established differs for the tasks on each side. That is, whereas the calling
task enters WAIT state after the rendezvous is established, the accepting task enters READY state.
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T-Kernel 1.B0.02