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Gerard Marull-Paretas 93b63df762 samples, tests: convert string-based twister lists to YAML lists Twister now supports using YAML lists for all fields that were written as space-separated lists. Used twister_to_list.py script. Some artifacts on string length are due to how ruamel dumps content. Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>		2023-05-10 09:52:37 +02:00
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src	samples, tests, boards: Switch main return type from void to int	2023-04-14 07:49:41 +09:00
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README.rst	samples: kernel: condvar: add README	2022-07-08 21:06:33 -04:00
sample.yaml	samples, tests: convert string-based twister lists to YAML lists	2023-05-10 09:52:37 +02:00

README.rst

.. _samples_kernel_condvar:

Condition Variables
###################

Overview
********

This sample demonstrates the usage of condition variables in a
multithreaded application. Condition variables are used with a mutex
to signal changing states (conditions) from one thread to another
thread. A thread uses a condition variable to wait for a condition to
become true. Different threads alternate between their entry point
function execution based on when they signal the other thread that is
pending on the condition variable. The sample can be used with any
:ref:`supported board <boards>` and prints the sample output shown to
the console.

Building and Running
********************

This application can be built and executed on Native Posix as follows:

.. zephyr-app-commands::
   :zephyr-app: samples/kernel/condition_variables/condvar
   :host-os: unix
   :board: native_posix
   :goals: run
   :compact:

To build for another board, change "native_posix" above to that board's name.

Sample Output
=============

.. code-block:: console

    Starting watch_count: thread 1
    watch_count: thread 1 Count= 0. Going into wait...
    inc_count: thread 2, count = 1, unlocking mutex
    inc_count: thread 3, count = 2, unlocking mutex
    inc_count: thread 2, count = 3, unlocking mutex
    inc_count: thread 3, count = 4, unlocking mutex
    inc_count: thread 2, count = 5, unlocking mutex
    inc_count: thread 3, count = 6, unlocking mutex
    inc_count: thread 2, count = 7, unlocking mutex
    inc_count: thread 3, count = 8, unlocking mutex
    inc_count: thread 2, count = 9, unlocking mutex
    inc_count: thread 3, count = 10, unlocking mutex
    inc_count: thread 2, count = 11, unlocking mutex
    inc_count: thread 3, count = 12  Threshold reached.Just sent signal.
    inc_count: thread 3, count = 12, unlocking mutex
    watch_count: thread 1 Condition signal received. Count= 12
    watch_count: thread 1 Updating the value of count...
    watch_count: thread 1 count now = 137.
    watch_count: thread 1 Unlocking mutex.
    inc_count: thread 2, count = 138, unlocking mutex
    inc_count: thread 3, count = 139, unlocking mutex
    inc_count: thread 2, count = 140, unlocking mutex
    inc_count: thread 3, count = 141, unlocking mutex
    inc_count: thread 2, count = 142, unlocking mutex
    inc_count: thread 3, count = 143, unlocking mutex
    inc_count: thread 2, count = 144, unlocking mutex
    inc_count: thread 3, count = 145, unlocking mutex
    Main(): Waited and joined with 3 threads. Final value of count = 145. Done.