Where is my lovely "/proc/net/arp" ?

main-pthread_exit.c

/*
 * Where is my lovely "/proc/net/arp" ? by M-Systems, Inc.
 */

#include <stdio.h>
#include <stdlib.h>

#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <unistd.h>

static void *thread(void *);

int
main(void)
{
	pthread_t thr;
	int error;

	error = pthread_create(&thr, NULL, thread, NULL);
	if (error != 0) {
		(void)fprintf(stderr, "pthread create error\n");
		pthread_exit(NULL);
	}

	(void)sleep(5);

	pthread_exit(NULL);
}

static void *
thread(void *aux)
{
	int fd, count, error;

	(void)aux; /* unused */

	error = pthread_detach(pthread_self());
	if (error != 0) {
		(void)fprintf(stderr, "pthread detach error\n");
		pthread_exit(NULL);
	}

	count = 1;
	while (/* CONSTCOND */ 1) {
		fd = open("/proc/net/arp", O_RDONLY, 0);
		if (fd == -1) {
			(void)fprintf(stderr, "open /proc/net/arp error\n");
			break;
		}
		if (close(fd) == -1) {
			(void)fprintf(stderr, "close /proc/net/arp error\n");
			break;
		}
		(void)printf("Count=%d\n", count++);
		(void)usleep(200 * 1000);
	}

	pthread_exit(NULL);
}