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/* $NetBSD: test_readhappy.c,v 1.1 2018/04/20 00:06:45 kamil Exp $ */
/*
* Copyright (c) 2018 The NetBSD Foundation, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <err.h>
#include <errno.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
/*
* Compile this program with -pthread and run it to test the readhappy_mpsafe
* module. This program should print out happy numbers read from /dev/happy_mpsafe.
* Insert the module and make the /dev/happy_mpsafe node before executing this file.
*/
static void* read_happy(void *);
static FILE *fp;
/*
* thread function used to read /dev/happy_mpsafe and print them out.
*/
static void *
read_happy(void *unused)
{
int line;
for (;;) {
fscanf(fp, "%d", &line);
printf("%d\n", line);
fflush(stdout);
}
/* NOTREACHED */
return NULL;
}
/*
* main function : opens /dev/happy_mpsafe and sets the global file descriptor
* creates 100 threads which try to use the file descriptor to read
* from /dev/happy_mpsafe.
* This function does not return anything and will run in an infinite loop.
*/
int
main(int argc, const char *argv[])
{
pthread_t thr[100];
fp = fopen("/dev/happy_mpsafe","r");
if (fp == NULL)
err(EXIT_FAILURE, "open");
for (int i = 0; i < 100; i++)
pthread_create(&thr[i], NULL, read_happy, NULL);
(void)read_happy(NULL);
/* NOTREACHED */
return EXIT_SUCCESS;
}
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