MATLAB: How do running MATLAB files, GUI callbacks, and timer callbacks interoperate in MATLAB 7.3 (R2006b)

MATLAB

I am trying to create a MATLAB application which behaves as a multithreaded application. With the use of a GUI and timers it seems like this is possible.

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MATLAB has a single main execution thread and all MATLAB code executes within that thread. Timers and GUI callback functions can execute preemptively while other code is running. This provides multithreaded-like behavior, however, all the MATLAB code is being executed in the single main thread.

In general, a MATLAB function or callback completes execution and then the next callback executes. Certain commands pause the currently executing MATLAB function and allow MATLAB to process callbacks and graphics events. These commands include DRAWNOW, KEYBOARD, INPUT, and PAUSE. Timer functions, however, execute between lines of a running MATLAB function. This can cause unexpected behavior in functions that are not reentrant safe. You should design your code to handle reentrancy and you should not depend on global variables that might change state during reentrancy.

For more details on DRAWNOW execute the command:

doc drawnow

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MATLAB: Is it possible to interrupt timer callbacks in MATLAB 7.14 (R2012a)

In contrast to GUI callbacks, which can be made interruptible using DRAWNOW or PAUSE commands, timer callbacks are not interruptible at all.

With regard to common MATLAB functions there are no limitations for interrupts. MATLAB functions can be interrupted between consecutive MATLAB commands. To make critical code sections safe, you would have to use mex files. This would allow to create some kind of semaphore or mutex.

MATLAB: How to get the timer object from within the timer’s callbacks, such as ‘TimerFcn’ and ‘StopFcn’

By default, the timer function callbacks pass the timer object as the first argument, and the event data associated with the callback as the second argument. Therefore, you always have access to the timer object from within its callback.

For more information and to see an example of how to define a timer callback, refer to the "Creating Callback Functions" section of the following URL:

 <http://www.mathworks.com/access/helpdesk/help/techdoc/index.html?/access/helpdesk/help/techdoc/matlab_prog/f9-39541.html>

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MATLAB: Is it possible to interrupt timer callbacks in MATLAB 7.14 (R2012a)

MATLAB: How to get the timer object from within the timer’s callbacks, such as ‘TimerFcn’ and ‘StopFcn’

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