A pure C implementation of the Observer Pattern
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Create something to be observed and other thing to be observing the first one;
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The observable (subject) includes
observer.handsubject.h. The observer only includes'observer.h. -
The subject needs to implement at least the subject's interface and two methods:
registerObserverandunregisterObserver. -
The observers then implement the observer interface and the
notifymethod, which is called when an event it is watching is triggered.
Check out the example for a better explanation on this.
In our example we have some animals, each of them defining a method that will be triggered when a cat meow.
As the animals act in a different manner, they'll, then, behave differently 
In technical terms, we have the CAT as the Subject (that object that the others wants to listen to) and the other ANIMALS as Observers (they implement a particular method to be triggered when the subject fires it).
The MIT License (MIT)
Copyright (c) <2014>
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