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/* Copyright (C) 2021 by Linaro */
/* Permission to use, copy, modify, and/or distribute this software for any */
/* purpose with or without fee is hereby granted. */
/* THE SOFTWARE IS PROVIDED AS IS AND THE AUTHOR DISCLAIMS ALL WARRANTIES */
/* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF */
/* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR */
/* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES */
/* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN */
/* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF */
/* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <poll.h>
#define TEST_SYSFS_NOTIFY "/sys/demo-poll/notify"
int main(void)
{
int notify_fd, rv, cnt;
char attr_data[100];
struct pollfd ufds;
if ((notify_fd = open(TEST_SYSFS_NOTIFY, O_RDWR)) < 0) {
printf("Unable to open %s", TEST_SYSFS_NOTIFY);
exit(1);
}
cnt = read(notify_fd, attr_data, 100);
lseek(notify_fd, 0, SEEK_SET);
ufds.fd = notify_fd;
ufds.events = POLLPRI | POLLERR;
ufds.revents = 0;
if ((rv = poll(&ufds, 1, 100000)) < 0) {
perror("poll error");
} else if (rv == 0) {
printf("Timeout occurred!\n");
} else if (ufds.revents & (POLLPRI | POLLERR)) {
cnt = read(notify_fd, attr_data, 100);
printf("sysfs_notify() triggered, revents: %08X,"
" attribute data[%d] %s", ufds.revents, cnt, attr_data);
}
close(notify_fd);
}
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