Need help to do the big task

Hi there,I AM STEVE.
Well I need to write a program to realize the inter-process communication with message quque, but when I finished it, the program when running seems to be blocked or just cann't send message to the user. the code like this:
server:

Code:

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#include"unistd.h"
#include"stdio.h"
#include"stdlib.h"
#include"sys/ipc.h"
#include"string.h"
#include"sys/msg.h"
#include"sys/stat.h"
#include"errno.h"

#define TEXT_SIZE 255

struct msg_buf{
        long type;
        char text[TEXT_SIZE+1];
};

int main()
{
        key_t key;
        int msg_id;
        struct msg_buf msg;

//=============================================================================
        if(key=ftok(".",'a')==-1){
                perror("Create key error.");
                exit(1);
        }
        printf("key=%d\n",key);

        if(msg_id=msgget(key,IPC_CREAT)==-1){
                perror("Create message error.");
                exit(1);
        }
        printf("msg_id=%d\n",msg_id);
//=============================================================================
        while(1){

                if(msgrcv(msg_id,&msg,sizeof(struct msg_buf),1, 0)!=-1){
                        printf("REC:%s from typ: %d\n",msg.text,msg.type);
                }

                int cmpret=strncmp(msg.text,"quit",4);
                msg.type=8888;
               
                printf("\nSend>");
                fgets(msg.text,sizeof(msg.text),stdin);
        //  strcpy(msg.text,"Ok!\n");
                msgsnd(msg_id,&msg,sizeof(struct msg_buf),0);
               
        //        printf("cmpret=%d\n",cmpret);
                if(cmpret==0){
                        break;
                }
                }
                msgctl(msg_id,IPC_RMID,NULL);
                exit(0);
}

---

client:

Code:

---

#define TEXT_SIZE 255

struct msg_buf{
        long type;
        char text[TEXT_SIZE+1];
};

int main(int argc,char **argv)
{
        key_t key;
        int        msg_id;
        struct msg_buf msg;
       
//        if(argc!=2){
//                fprintf(stderr,"Usage:%s'your message string'\n",argv[0]);
//                exit(1);
//        }
//=============================================================================
        if(key=ftok(".",'a')==-1){
                perror("Create key error.");
                exit(1);
        }
        printf("key=%d\n",key);

        if(msg_id=msgget(key,IPC_CREAT)==-1){
                perror("Create message error.");
                exit(1);
        }
        printf("msg_id=%d\n",msg_id);
//=============================================================================
                msg.type=1;
        //        strncpy(msg.text,argv[1],TEXT_SIZE);
            printf("\nSend>");
                fgets(msg.text,sizeof(msg.text),stdin);
                msgsnd(msg_id,&msg,sizeof(struct msg_buf),0);

                memset(&msg,'\0',sizeof(struct msg_buf));
                msgrcv(msg_id,&msg,sizeof(struct msg_buf),8888, 0);
                fprintf(stdout,"Client recieve:%s,type:%d\n",msg.text,msg.type);
                exit(0);
}

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Now they can't communicate with each other.Why?Thanks for your time.

The client/server code looks good, and the problem is of a more mundane nature

Code:

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if (msg_id=msgget(key,IPC_CREAT)==-1) /* which has higher precedence - the equality or assignment operator? */

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