nanospin_ns()

Ожидать без блокировки в течение заданного промежутка времени

Прототип:

#include <time.h>
int nanospin_ns( unsigned long nsec );

Аргументы:

nsec
The number of nanoseconds that you want to busy-wait for.

Библиотека:

libc

Описание:

The nanospin_ns() function busy-waits for the number of nanoseconds specified in nsec, without blocking the calling thread.


Note: The nanospin*() functions are designed for use with hardware that requires short time delays between accesses. You should use them to delay only for times less than a few milliseconds. For longer delays, use the POSIX timer_*() functions.

Because of the nature of time measurement, the function might actually wait longer than the specified time.


The first time you call nanospin_ns(), the C library invokes nanospin_calibrate() with an argument of 0 (interrupts enabled), if you haven't invoked it directly first.

Возвращаемое значение:

EOK
Успешное завершение.
E2BIG
The delay specified by nsec is greater than 500 milliseconds.

Note: A delay of more than a few milliseconds might not work on some processors. For longer delays, use the POSIX timer_*() functions.

EINTR
A too-high rate of interrupts occurred during the calibration routine.
ENOSYS
This system's startup-* program didn't initialize the timing information necessary to use nanospin_ns().

Классификация:

ЗОСРВ «Нейтрино»

Точка остановки потока
Нет
Обработчик прерываний
Смотри ниже
Обработчик сигналов
Да
В потоке
Да

Предостережения:

You should use busy-waiting only when absolutely necessary for accessing hardware.

It isn't safe to call this function in an interrupt handler if nanospin_calibrate() hasn't been called yet.

Тематические ссылки:

nanosleep(), nanospin(), nanospin_calibrate(), nanospin_count(), nanospin_ns_to_count(), sched_yield(), sleep(), timer_create()




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