9fe370ef36
Added README.rst for eventfd and uname samples. Updated README for gettimeofday to align with other READMEs.Updated Makefile.host file for samples to store output file in 'build' directory. Signed-off-by: Doug Foster <dougwfost@gmail.com>
45 lines
1.4 KiB
ReStructuredText
45 lines
1.4 KiB
ReStructuredText
.. _posix-gettimeofday-sample:
|
|
|
|
POSIX gettimeofday() with clock initialization over SNTP
|
|
########################################################
|
|
|
|
Overview
|
|
********
|
|
|
|
This sample application demonstrates using the POSIX `gettimeofday()`_ function to display the
|
|
absolute wall clock time and local time every second. At system startup, the current time is
|
|
queried using the SNTP networking protocol, enabled by setting the
|
|
:kconfig:option:`CONFIG_NET_CONFIG_CLOCK_SNTP_INIT` and
|
|
:kconfig:option:`CONFIG_NET_CONFIG_SNTP_INIT_SERVER` options.
|
|
|
|
Requirements
|
|
************
|
|
|
|
- :ref:`networking_with_host`
|
|
- or, a board with hardware networking
|
|
- NAT/routing should be set up to allow connections to the Internet
|
|
- DNS server should be available on the host to resolve domain names
|
|
|
|
Building and Running
|
|
********************
|
|
|
|
This project outputs to the console. It can be built and executed on QEMU as follows:
|
|
|
|
.. zephyr-app-commands::
|
|
:zephyr-app: samples/posix/gettimeofday
|
|
:host-os: unix
|
|
:board: qemu_x86
|
|
:goals: run
|
|
:compact:
|
|
|
|
For comparison, to build directly for your host OS if it is POSIX compliant (for ex. Linux):
|
|
|
|
.. code-block:: console
|
|
|
|
cd samples/posix/gettimeofday
|
|
make -f Makefile.host
|
|
|
|
The make output file will be located in samples/posix/gettimeofday/build.
|
|
|
|
.. _gettimeofday(): https://pubs.opengroup.org/onlinepubs/009604599/functions/gettimeofday.html
|