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os/tp2/doc/semaphore.plantuml

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+@startuml semaphore
+title Sémaphore
+
+binary "Tâche 1" as t1
+concise "Sémaphore" as s
+binary "Tâche 2" as t2
+binary "Tâche 3" as t3
+
+scale 1000 as 100 pixels
+
+@0
+t1 is low
+t2 is low
+t3 is low
+s is "Verrouillé"
+
+
+@+3000
+t1 is high
+
+@+400
+t1 is low
+t2 is high
+s is {-}
+t1 -> s  : lib.
+s  -> t2 : rév.
+note top of s : T.1 libère la sémaphore\nT.2 est réveillé et verrouille la sémaphore
+
+@+400
+t2 is low
+s is "Verrouillé"
+t2 -> s  : verr.
+
+@+2200
+t1 is high
+
+@+400
+t1 is low
+t2 is high
+s is {-}
+t1 -> s  : lib.
+s  -> t2 : rév.
+
+@+400
+t2 is low
+s is "Verrouillé"
+t2 -> s  : verr.
+
+
+@1000
+t3 is high
+@+100
+t3 is low
+@+900
+t3 is high
+@+100
+t3 is low
+@+900
+t3 is high
+@+100
+t3 is low
+@+900
+t3 is high
+@+100
+t3 is low
+@+900
+t3 is high
+@+100
+t3 is low
+@+900
+t3 is high
+@+100
+t3 is low
+
+@enduml