操作系统实验代码

snd.c

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>
#include <stdio.h>
#define key  80
struct msg {
   long mtype;
    int snd_id;
    char txt[128];
};
int len=sizeof(struct msg) - sizeof(long);
main()
{
     int qid;
     struct msg m;
     qid=msgget(key,0777|IPC_CREAT);	
     m.mtype=1;	
     m.snd_id=getpid(); 
     strcpy(m.txt,"aaaaa");   
    printf("qid=%d\n",qid);
    msgsnd(qid,&m,len,0);
    msgrcv(qid,&m,len,getpid(),0);
    printf("pid=%d,%s\n",m.snd_id,m.txt);
    getchar();	
}	  

rcv.c

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>
#include <stdio.h>
#define key  80
struct msg {
   long mtype;
    int snd_id;
    char txt[128];
};
int len=sizeof(struct msg) - sizeof(long);
main()
{
     int qid;
     int pid=getpid();
     struct msg m;
     qid=msgget(key,0777);	
    printf("qid=%d",qid);
    msgrcv(qid,&m,len,1,0);
    printf("pid=%d,%s\n",m.snd_id,m.txt);
     m.mtype=m.snd_id;	
     m.snd_id=pid; 
     strcpy(m.txt,"bbbbb");
    msgsnd(qid,&m,len,0);
    getchar();
}