2024-08-24 00:47:19 +08:00
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.. zephyr:code-sample:: posix-eventfd
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:name: eventfd()
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2024-01-10 12:45:25 +08:00
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2024-08-24 00:47:19 +08:00
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Use ``eventfd()`` to create a file descriptor for event notification.
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2024-01-10 12:45:25 +08:00
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Overview
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********
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This sample application demonstrates using the POSIX eventfd() function to create a file descriptor,
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which can be used for event notification. The returned file descriptor is used with write/read calls
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and write/read values are output to the console.
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Building and Running
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********************
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This project outputs to the console. It can be built and executed on QEMU as follows:
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.. zephyr-app-commands::
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:zephyr-app: samples/posix/eventfd
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:host-os: unix
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:board: qemu_x86
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:goals: run
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:compact:
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For comparison, to build directly for your host OS if it is POSIX compliant (for ex. Linux):
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.. code-block:: console
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cd samples/posix/eventfd
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make -f Makefile.host
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The make output file will be located in samples/posix/eventfd/build.
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Sample Output
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=============
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.. code-block:: console
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Writing 1 to efd
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Writing 2 to efd
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Writing 3 to efd
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Writing 4 to efd
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Completed write loop
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About to read
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Read 10 (0xa) from efd
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Finished
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