Hi Jean-René,

I have analyzed your code and I don't know if I am mistaken, but I believe that he is similar to do:
DO process1
Do process2

Process2 is not executed until the process1 finishes.
Am I mistaken?

But what I want it is the concept of semaphores, in which the process that calls it, is blocked untiluntil it happens an event . I don't want to wait for the conclusion of another process, but to the activation of semaphore (event).

In the following table I indicate how I want the concurrence of processes.
---------------------------------
|Time | RUN | BLOCKED |
---------------------------------
| 0 | P1 | |
---------------------------------
| 1 | P2 | P1 |
---------------------------------
| 2 | P1 | P2 |
---------------------------------
| 3 | P2 | | P1 finishes
---------------------------------

Excuse by my ingles. Perhaps I do not explain myself well.

Thanks.