UDP Server

Bewin

Mar 24th, 2025

212

Never

Add comment

Not a member of Pastebin yet? Sign Up, it unlocks many cool features!

C 1.96 KB | None | 0 0

raw download clone embed print report

#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <unistd.h>
int main(void){
int socket_desc;
struct sockaddr_in server_addr, client_addr;
char server_message[2000], client_message[2000];
int client_struct_length = sizeof(client_addr);
// Clean buffers:
memset(server_message, '\0', sizeof(server_message));
memset(client_message, '\0', sizeof(client_message));
// Create UDP socket:
socket_desc = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if(socket_desc < 0){
printf("Error while creating socket\n");
return -1;
}
printf("Socket created successfully\n");
// Set port and IP:
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(2000);
server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
// Bind to the set port and IP:
if(bind(socket_desc, (struct sockaddr*)&server_addr, sizeof(server_addr)) < 0){
printf("Couldn't bind to the port\n");
return -1;
}
printf("Done with binding\n");
printf("Listening for incoming messages...\n\n");
// Receive client's message:
if (recvfrom(socket_desc, client_message, sizeof(client_message), 0,
(struct sockaddr*)&client_addr, &client_struct_length) < 0){
printf("Couldn't receive\n");
return -1;
}
printf("Received message from IP: %s and port: %i\n",
inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
printf("Msg from client: %s\n", client_message);
// Respond to client:
strcpy(server_message, client_message);
if (sendto(socket_desc, server_message, strlen(server_message), 0,
(struct sockaddr*)&client_addr, client_struct_length) < 0){
printf("Can't send\n");
return -1;
}
// Close the socket:
close(socket_desc);
return 0;
}

Add Comment

Please, Sign In to add comment