read.c

进程间通信的实验代码

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <sys/msg.h>
#include <sys/ipc.h>
#include "message.h"
#define SEGSIZE 	sizeof(struct mymsgbuf)

main()
{
	struct mymsgbuf studentinfo;
	int shmid;
	key_t key;
	char *segptr;
	key=ftok(".",'S');
	if((shmid = shmget(key, SEGSIZE, 0)) == -1)
	{
			perror("shmget not exist\n" );
			exit(1);
	}
	/* Attach (map) the shared memory segment into the current process */
	if((segptr = shmat(shmid, 0, 0)) == -1)
	{
		perror("shmat");
		exit(1);
	}
	//read data from share memory.
	memcpy(&studentinfo,segptr,sizeof (struct mymsgbuf));

    printf("you receive info:\n");
	printf("\tid:\t %s\n",studentinfo.id);
	printf("\tname:\t %s\n",studentinfo.name);
	printf("\tage:\t %d\n",studentinfo.age);
	printf("\tE_mail:\t %s\n\n",studentinfo.e_mail);
	
	exit(0);
}