Bad Address Error Reading from Message Queue on Linux

I have an appointment when I need to write a simple time server and client using the Linux message queue. The server opens a message queue, and the client sends a request with its PID (message with type 1), and the server reads this message and sends a message with the PID type (taken from the read message). I put all the code below because I don’t know where I made a mistake. I am not a Linux programming expert. I don’t even know if I wrote the server correctly.

A file that is included by the server and client (I need to write it this way).

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

#define QUEUE 100
#define PERM_ALL 0777

typedef struct my_msgbuf {
    long mtype;
    int pid;
} ClientMessage;

typedef struct my_msgbuf2 {
    long mtype;
    struct tm time;
} TimeMessage;

Server

int m_queue;

void cleanup(int signum) {
    if (msgctl(m_queue, IPC_RMID, NULL) == -1) {
        printf("Something happen on clean up\n");
        exit(1);
    }
    exit(signum);
}

int main() {
    ClientMessage pid_message;
    TimeMessage t;
    time_t clock;
    struct tm *cur_time;

    if ((m_queue = msgget(QUEUE, PERM_ALL | IPC_CREAT)) == -1) {
        printf("Can't create and open message queue\n");
        exit(1);
    }
    printf("created message queue = %d\n", m_queue);
    fflush(stdout);
    //t = malloc(sizeof(TimeMessage));
    signal(SIGINT, cleanup);

    while (1) {
        if (msgrcv(m_queue, &pid_message, sizeof(pid_message.pid), 1, 0) == -1) {
            break;
        } else {
            t.mtype = pid_message.pid;
            clock = time(NULL);
            cur_time = localtime(&clock);
            memcpy(&t.time, cur_time, sizeof(struct tm));
            msgsnd(m_queue, &t, sizeof(struct tm), 0);
        }
    }

    cleanup(0);
}

Client

int main() {
    int m_queue;
    TimeMessage *t;
    ClientMessage client;

    if ((m_queue = msgget(QUEUE, PERM_ALL)) == -1) {
        perror("Error in opening queue");
        exit(1);
    }

    client.mtype = 1;
    client.pid = getpid();

    while (1) {
        if (msgsnd(m_queue, &client, sizeof(client.pid), 0) == -1) {
            perror("Error sending to queue");
            exit(1);
        } else {
            if (msgrcv(m_queue, t, sizeof(struct tm), client.pid, 0) == -1) {
                perror("Error reading from queue");
                exit(1);
            }   
            printf("time: %d:%d:%d\n", t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
        }
    }
    return 0;
}

Both programs compile without errors, but return to the client "Error reading from the queue" msgrcv returns -1.

+3
1

perror "Bad Address" (EFAULT), , ", msgp (), ". , TimeMessage *t, , TimeMessage t &t t msgrcv. sizeof t ( , *t t sizeof(TimeMessage) *t) sizeof(struct tm) (& , printf)

, !

+5

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