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#The Pymoult API

This page gives general directions to the Pymoult API, to get more details about the functions and classes the pydoc can be build from the sources.

##DSU Threads

The DSU_Thread class from the pymoult.threads module enables some DSU features while providing the features of regular threads.

Thread reboot

If a RebootException is raised inside a DSU Thread, the thread will stop its execution and restart again. The method to be run can be changed before rebooting (by changing the function held by the main method of the thread).
Continuation support

When a DSU_Thread starts, it generates a continuation that is put to sleep immediately. The switch method can be used to switch to that continuation. Switching to the sleeping continuation will cause the sleeping_continuation_function method of the thread to be called if it has been defined before returning to the thread main execution.
Active and Passive Updates

When using static alterability detection, the update can be donc by the thread (active update) or by a manager (passive update). When initiating the DSU_Thread, a active parameter can be set to True to precise that when reaching a staticUpdatePoint (from pymoult.lowlevel.alterability), the thread should run its active_update_function. If the active parameter is False (it is by default), when reaching a staticUpdatePoint and if wait_static_points (from pymoult.lowlevel.alterability) has been called, the thread will suspend itself and notify that it has reached an update point.

Using DSU_Thread is similar to regular threads from the threading module, except the method to be run by the thread has to be named main.

The pymoult.threads module provides other utility functions such as

start_active_update starts an update within the thread (see the DSU page for the mechanism description)
set_active_update_function sets the update function for next active update (see the DSU page for the mechanism description)
get_thread_by_name returns the thread with the name given as argument
set_thread_trace takes a thread and a trace as arguments and sets the given trace for the given thread, then triggers it immediately.

##High level API

The high level API of Pymoult contains three types of class. The Listener class opens a socket for suppliying future updates. It has to be started in the application. The Manager classes uses the DSU mechanisms from the low level to watch the application and apply modifications to it. The Update classes configure the Manager classes by precising the targets of the update.

##Low Level API

The low level API provides a set of functions and classes implementing basic DSU mechanisms. They are spread among different modules, depending on the issue they address. Each low level function provided by these modules are to be used as parts of Update classes. The functions must be called by the methods of these Update classes.