Sending messages between two processes

The following two programs should  run at the same time to illustrate basic principle of message passing.
The first program creates a message queue and sends one message to the queue.
The second program reads the message from the queue.

creating and sending to a simple message queue

The full code listing for message_send.c is as follows:

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

#define MSGSZ     128

/* Declare the message structure. */

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

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

    /* Get the message queue id for the"name" 1234, 
     which was created bythe server.*/
    key = 1234;
    if ((msqid = msgget(key, msgflg )) < 0) {
        perror("msgget");
        exit(1);
    }
    /* Prepare message type 1*/   
    sbuf.mtype = 1; 
    (void) strcpy(sbuf.mtext, "This is my message");
    buf_length = strlen(sbuf.mtext) ;

    /* Send the message. */
    if (msgsnd(msqid, &sbuf, buf_length, IPC_NOWAIT) < 0) {
       printf ("Error- message not sent");
       exit(1);
    }
    printf("Message sent" Sent\n");
    exit(0);
}

receiving the above message

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

#define MSGSZ     128

/* Declare the message structure  */

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

main(){
    int msqid;
    key_t key;
    message_buf  rbuf;

    /* Get the message queue id for the "name" 1234, 
       which was created by the server.*/
    key = 1234;
    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("message not reedceived");
        exit(1);
    }

    /* Print the answer.  */
    printf("Received message: %s\n", rbuf.mtext);
    exit(0);
}