socket programming

[preveen-stack]

Here is an example of a basic socket program in C for macOS (formerly known as OS X):

#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>

int main(int argc, char *argv[]) {

    // Create a socket
    int socket_desc = socket(AF_INET, SOCK_STREAM, 0);

    if (socket_desc == -1) {
        printf("Could not create socket");
    }

    // Prepare the sockaddr_in structure
    struct sockaddr_in server;
    server.sin_addr.s_addr = inet_addr("127.0.0.1"); // server IP address
    server.sin_family = AF_INET;
    server.sin_port = htons(8888); // server port

    // Connect to remote server
    if (connect(socket_desc, (struct sockaddr *)&server, sizeof(server)) < 0) {
        printf("Connect error");
        return 1;
    }

    // Send some data
    char *message = "Hello server!";
    if (send(socket_desc, message, strlen(message), 0) < 0) {
        printf("Send failed");
        return 1;
    }

    printf("Data sent\n");

    return 0;
}

This program creates a TCP socket, connects to a remote server (in this case, at IP address 127.0.0.1 and port 8888), and sends a message to it. You can compile and run this program on macOS using the following commands:

$ gcc -o client client.c
$ ./client

Note that you will need a server program running at the specified IP address and port for this client to connect to.