Programming

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>
#include <string.h>

#define MSGSZ     128

#define mess    122


 typedef struct msgbuf {
          long    mtype;
          char    mtext[MSGSZ];
          } message_buf;

//for reciving structure
typedef struct msg1 {
         long    type;
         char    message[mess];
         } mess_buf;

main()
{
    int msqid;
    int msgflg = IPC_CREAT | 0666;
    key_t key;
    size_t buf_length;
    message_buf sbuf;
    key = 1234;

// for reciving the data

    int msgid;
    int msgflag = IPC_CREAT | 0666;
    key_t lock;
    mess_buf gbuf;
//     size_t buffer_length;

    lock = 123;
    

(void) fprintf(stderr, "\nmsgget: Calling msgget(%#lx,%#o)\n",key, msgflg);

    if ((msqid = msgget(key, msgflg )) < 0) {
        perror("msgget");
        exit(1);
    }
    else 
     (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msqid);

     // We'll send message type 1


    sbuf.mtype = 1;

    (void) strcpy(sbuf.mtext, "Did you get this?");

    buf_length = strlen(sbuf.mtext) + 1 ;

     //Send a message.
     
    if (msgsnd(msqid, &sbuf, buf_length, IPC_NOWAIT) < 0) {
       printf ("%d, %d, %s, %d\n", msqid, sbuf.mtype, sbuf.mtext, buf_length);
        perror("msgsnd");
        exit(1);
    }

   else 
      printf("Message: \"%s\" Sent\n", sbuf.mtext);
      
//     exit(0);

//this is to recive the message


(void) fprintf(stderr, "\nmsgget: Calling msgget(%#lx,%#o)\n",lock, msgflag);

    if ((msgid = msgget(lock, msgflag )) < 0) {
        perror("msgget");
        exit(1);
    }
    else 
     (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msgid);


    
    
      //recive the message form the sender

    if (msgrcv(msgid, &gbuf,mess, 1, 0) < 0) {
        perror("msgrcv");
        exit(1);
    }

    
     // Print the answer.
     
    printf("recived:%s\n", gbuf.message);
    exit(0);


}

client.c

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>

#define MSGSZ     128

#define mess    122

typedef struct msgbuf {
    long    mtype;
    char    mtext[MSGSZ];
} message_buf;

// for sending structure

typedef struct msg1 {
         long    type;
         char message[mess];
         } mess_buf;


main()
{
    int msqid;
    key_t key;
    int msgflg = IPC_CREAT | 0666;
    message_buf  rbuf;
    key = 1234;

// for the tranmission

 int msgid;
    int msgflag = IPC_CREAT | 0666;
    key_t lock;
    mess_buf tbuf;
    size_t buf_length;
    lock = 123;

// reciving starts here

    if ((msqid = msgget(key, 0666)) < 0) {
        perror("msgget");
        exit(1);
    }

     // Receive an answer of message type 1.
     
    if (msgrcv(msqid, &rbuf, MSGSZ, 1, 0) < 0) {
        perror("msgrcv");
        exit(1);
    }
 
    printf("%s\n", rbuf.mtext);
//     exit(0);


// now we r sending the message to the server



(void) fprintf(stderr, "\nmsgget: Calling msgget(%#lx,\%#o)\n",lock, msgflag);

    if ((msgid = msgget(lock, msgflag )) < 0) {
        perror("msgget");
        exit(1);
    }
    else 
     (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msgid);


    tbuf.type = 1;
 
    (void) strcpy(tbuf.message, "r u hearing me?");
     buf_length = strlen(tbuf.message) + 1 ;
     // Send a message.
     
    if (msgsnd(msgid, &tbuf, buf_length, IPC_NOWAIT) < 0) {
        printf ("%d, %d, %s, %d\n", msgid, tbuf.type, tbuf.message, buf_length);
        perror("msgsnd");
        exit(1);
    }

   else 
      printf("Message: \"%s\" Sent\n", tbuf.message);

    exit(0);

}