Sample Mach Message

ViewController.m

//
//  ViewController.m
//  SampleMachMessage
//
//  Created by Ali Pourhadi on 2019-09-21.
//  Copyright © 2019 Ali Pourhadi. All rights reserved.
//

#import "ViewController.h"

typedef struct {
    mach_msg_header_t header;
} mach_message;

@implementation ViewController {
    mach_message sentMessage;
    mach_message receivedMessage;
    kern_return_t err;
    mach_port_t port;
    int messageId;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    messageId = 0;
    port = MACH_PORT_NULL;
    err = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &port); // Creating a port for comminucation
    if (err != KERN_SUCCESS) {
        printf("Failed to Allocate a port \n");
    }
    [self performSelectorInBackground:@selector(getMessage) withObject:nil];
    [NSTimer scheduledTimerWithTimeInterval:3.0 repeats:true block:^(NSTimer * _Nonnull timer) {
        [self sendMessage];
    }];
}
- (void)sendMessage {
    sentMessage.header.msgh_id = messageId++; /* MessageId */
    sentMessage.header.msgh_remote_port = port; /*Destination Port*/
    sentMessage.header.msgh_local_port = MACH_PORT_NULL;
    sentMessage.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND, 0);
    sentMessage.header.msgh_size = sizeof(mach_message);
    err = mach_msg (&sentMessage.header,            /* The header */
                    MACH_SEND_MSG,    /* Flags */
                    sizeof (sentMessage),            /* Send size */
                    0,            /* Max receive Size */
                    MACH_PORT_NULL,                /* Receive port */
                    MACH_MSG_TIMEOUT_NONE,        /* No timeout */
                    MACH_PORT_NULL);            /* No notification */
}

-(void)getMessage {
    int err;
    receivedMessage.header.msgh_local_port = port;
    receivedMessage.header.msgh_size = sizeof (mach_message);
    while (true)
    {
        /* Receive a message.  */
        err = mach_msg (&receivedMessage.header,        /* The header */
                        MACH_RCV_MSG,        /* Flags */
                        0, sizeof (mach_message),    /* Send/Max receive size */
                        port,            /* Receive port */
                        MACH_MSG_TIMEOUT_NONE,    /* No timeout */
                        MACH_PORT_NULL);        /* No notification */
        printf ("message: %i ", receivedMessage.header.msgh_id);
    }
}

- (void)setRepresentedObject:(id)representedObject {
    [super setRepresentedObject:representedObject];

    // Update the view, if already loaded.
}

@end