实验4

fifo_write.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>


#define FIFO "myfifo"
#define BUFF_SIZE 1024


int main(int argc, char* argv[]) {
    char buff[BUFF_SIZE];
    int real_write;
    int fd;
    int rw = 1;

    if (access(FIFO, F_OK) == -1) {
        if ((mkfifo(FIFO, 0666) < 0) && (errno != EEXIST)) {
            printf("Can NOT create fifo file!\n");
            exit(1);
        }
    }

    if ((fd = open(FIFO, O_WRONLY)) == -1) {
        printf("Open fifo error!\n");
        exit(1);
    }

    do {
        printf("请输入要写入管道的内容：\n");
        fgets(buff, BUFF_SIZE, stdin);
        if ((real_write = write(fd, buff, strlen(buff))) > 0)
            printf("第%d次写入管道：'%s'.\n", rw++, buff);
    } while (strlen(buff) != 0);

    close(fd);
    exit(0);
}

fifo_read.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<sys/types.h>
#include<sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>

#define FIFO "myfifo"
#define BUFF_SIZE 1024


int main() {
    char buff[BUFF_SIZE];
    int real_read;
    int fd;
    int rc = 1;

    if (access(FIFO, F_OK) == -1) {
        if ((mkfifo(FIFO, 0666) < 0) && (errno != EEXIST)) {
            printf("Can NOT create fifo file!\n");
            exit(1);
        }
    }

    if ((fd = open(FIFO, O_RDONLY)) == -1) {
        printf("Open fifo error!\n");
        exit(1);
    }

    while (1) {
        memset(buff, 0, BUFF_SIZE);
        if ((real_read = read(fd, buff, BUFF_SIZE)) > 0)
            printf("第%d次读取管道： '%s'.\n", rc++, buff);
        else

            break;
    }

    close(fd);
    exit(0);
}

shmmutexwrite.c

#include<semaphore.h>
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/ipc.h>
#include<sys/sem.h>
#include<sys/shm.h>
#include<sys/stat.h>
#include<fcntl.h>
#include<string.h>
#define BUFFER_SIZE 10
#define sem_name"mysem"
int main()
{
	struct People
	{
		char name[10];
		int age;
	};
	int shmid;
	sem_t*sem;
	int age=10,i=1;
	char buff[BUFFER_SIZE];
	key_t shmkey;
	shmkey=ftok("shmmutexread.c",0);
	sem=sem_open(sem_name,O_CREAT,0644,1);
	if(sem==SEM_FAILED)
	{
		printf("unable to creat semaphore!");
		sem_unlink(sem_name);
		exit(-1);
	}
	shmid=shmget(shmkey,1024,0666|IPC_CREAT);
	if(shmid==-1)
		printf("creat shm is fail\n");
	struct People * addr;
	addr=(struct People*)shmat(shmid,0,0);
	if(addr==(struct People*)-1)
		printf("shm shmat is fail\n");
	addr->age=0;
	printf("写进程映射的共享内存地质=%p\n",addr);
	do
	{
		sem_wait(sem);
		memset(buff,0,BUFFER_SIZE);
		memset((addr+i)->name,0,BUFFER_SIZE);
		printf("写进程:输入一些姓名(不超过10个字符)到共享内存(输入'quit'退出):\n");
	if(fgets(buff,BUFFER_SIZE,stdin)==NULL)
	{
		perror("fgets");
		sem_post(sem);
		break;
	}
	strncpy((addr+i)->name,buff,strlen(buff)-1);
	(addr+i)->age=++age;
	addr->age++;
	i++;
	sem_post(sem);
	sleep(1);
	}while(strncmp(buff,"quit",4)!=0);
	if(shmdt(addr)==-1)
		printf("shmdt is fail\n");
	sem_close(sem);
	sem_unlink(sem_name);
}

shmmutexread.c

#include<semaphore.h>
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/ipc.h>
#include<sys/sem.h>
#include<sys/shm.h>
#include<sys/stat.h>
#include<fcntl.h>
#include<string.h>
#define sem_name"mysem"
int main()
{
	int shmid;
	sem_t*sem;
	int i=1;
	key_t shmkey;
	shmkey=ftok("shmmutexread.c",0);
	struct People
	{
		char name[10];
		int age;
	};
	sem=sem_open(sem_name,0,0644,0);
	if(sem==SEM_FAILED)
	{
		printf("unable to open semaphore!");
		sem_close(sem);
		exit(-1);
	}
	shmid=shmget(shmkey,0,0666);
	if(shmid==-1)
	{
		printf("creat shm is fail\n");
		exit(0);
	}
	struct People*addr;
	addr=(struct People*)shmat(shmid,0,0);
	if(addr==(struct People*)-1)
	{
		printf("shm shmat is fail\n");
		exit(0);
	}
	printf("读进程映射的共享内存地址=%p\n",addr);
	do
	{
		sem_wait(sem);
		if(addr->age>0)
		{
			printf("\n读进程:绑定到共享内存%p:姓名%d %s,年龄%d \n", addr,1,(addr+i)->name,(addr+i)->age);
		addr->age--;
		if(strncmp((addr+i)->name,"quit",4)==0) break;
		i++;
	}
	sem_post(sem);
	}while(1);
	sem_close(sem);
	if(shmdt(addr)==-1) printf("shmdt is fail\n");
	if(shmctl(shmid,IPC_RMID,NULL)==-1)
	printf("shmctl delete error\n");
}