Server

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define PORT 5150

// Server that will continue listening on defined port even after client disconnects

int main(){

    int sockfd, ret;
    struct sockaddr_in serverAddr;

    int newSocket;
    struct sockaddr_in newAddr;

    socklen_t addr_size;

    int buff_size = 256;
    char buffer[buff_size];
    double dbuffer[1];
    pid_t childpid;

    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if(sockfd < 0){
        printf("[-]Error in connection.\n");
        exit(1);
    }
    printf("[+]Server Socket is created.\n");

    int enable = 1;
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &enable,sizeof(int) ) < 0)
    {
        printf("[-]Could not set the socket option.\n");
    }

    int priority = 128; // 100 000
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &priority, sizeof(priority) ) < 0)
    {
        printf("[-]Could not set the socket priority\n");
    }

    memset(&serverAddr, '\0', sizeof(serverAddr));
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(PORT);
    serverAddr.sin_addr.s_addr = inet_addr("192.168.88.254");

    ret = bind(sockfd, (struct sockaddr*)&serverAddr, sizeof(serverAddr));
    if(ret < 0){
        printf("[-]Error in binding.\n");
        exit(1);
    }
    printf("[+]Bind to port %d\n", PORT);

    if(listen(sockfd, 10) == 0)
    {
        printf("[+]Listening....\n");
    }
    else
    {
        printf("[-]Error in binding.\n");
    }


    while(1)
    {
        newSocket = accept(sockfd, (struct sockaddr*)&newAddr, &addr_size);
        if(newSocket < 0)
        {
            exit(1);
        }
        printf("Connection accepted from %s:%d\n", inet_ntoa(newAddr.sin_addr), ntohs(newAddr.sin_port));

        if((childpid = fork()) == 0)
        {
            close(sockfd);

            do
            {
                recv(newSocket, dbuffer, sizeof(dbuffer), 0);
                printf("Received %f\n", dbuffer[0]);

                dbuffer[0]=dbuffer[0]+1;

                printf("Sending %f\n", dbuffer[0]);
                send(newSocket, dbuffer, sizeof(dbuffer), 0);
            }
            while ( dbuffer[0] < 2000);
        }

        close(newSocket);
    }

    return 0;
}