Problematic socket server - c

Question

I'm trying to create a server-client socket scenario, in which more than one clients communicate with a server through socket. Server reads the data and sends back some acknowledgement and parallel saves some data.
My server.c code:
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
void serve(int);
struct data {
int checked;
int all;
}Data;
int main(int argc, char *argv[]) {
int sockfd, newsockfd, portno;
struct sockaddr_in serv_addr, cli_addr;
int pid;
socklen_t clilen;
if (argc < 2) {
fprintf(stderr,"ERROR: NO PORT PROVIDED!\n");
exit(1);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0) {
fprintf(stderr,"ERROR: CANNOT CREATE SOCKET!\n");
exit(1);
}
bzero((char *) &serv_addr, sizeof(serv_addr));
portno = atoi(argv[1]);
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(portno);
if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
fprintf(stderr,"ERROR: CANNOT BIND CONNECTION!\n");
exit(1);
}
listen(sockfd,5);
clilen = sizeof(cli_addr);
while (1) {
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
if (newsockfd < 0) {
fprintf(stderr,"ERROR: CANNOT ACCEPT NEW CONNECTION!\n");
exit(1);
}
pid = fork();
if (pid < 0) {
fprintf(stderr,"ERROR: CANNOT CREATE NEW PROCESS!\n");
exit(1);
}
if (pid == 0) {
close(sockfd);
serve(newsockfd);
exit(0);
}
else
close(newsockfd);
}
return 0;
}
void serve(int new) {
int n;
int buffer[256];
int sum = 0;
int m = 0;
int i = 0;
int size = 0;
bzero(buffer, 256);
n = read(new, buffer, 256);
if (n == NULL) {
fprintf(stderr, "ERROR: CANNOT READ FROM CLIENT!\n");
exit(1);
}
do {
size++;
i++;
}while (buffer[i] != 0);
for (i = 0; i < size; i++)
sum += buffer[i];
m = sum / size;
sum = 0;
if (m > 10) {
Data.checked++;
Data.all++;
n = write(new, "Sequence OK", 11);
if (n == NULL) {
fprintf(stderr, "ERROR: CANNOT WRITE TO CLIENT!\n");
exit(1);
}
} else {
Data.all++;
n = write(new, "Check failed", 12);
}
printf("Data so far:\n1)Number of sequences received: %d\n2)Number of sequences with average above 10: %d\n", Data.all, Data.checked);
}
And my client.c code is:
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <memory.h>
int main(int argc, char *argv[]) {
int sockfd, portno, n;
struct sockaddr_in serv_addr;
struct hostent *server;
int buffer[256];
char buffer2[13];
char answer;
int i;
int size = 0;
if (argc < 3) {
fprintf(stderr,"ERROR: CANNOT USE %s PORT!\n", argv[0]);
exit(0);
}
portno = atoi(argv[2]);
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0){
fprintf(stderr, "ERROR: CANNOT CREATE SOCKET!\n");
exit(1);
}
server = gethostbyname(argv[1]);
if (server == NULL) {
fprintf(stderr,"ERROR: NO HOST FOUND!\n");
exit(1);
}
bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
bcopy(server->h_addr, (char *)&serv_addr.sin_addr.s_addr, server->h_length);
serv_addr.sin_port = htons(portno);
if (connect(sockfd,(struct sockaddr *)&serv_addr,sizeof(serv_addr)) < 0) {
fprintf(stderr, "ERROR: CANNOT CONNECT TO SERVER!\n");
exit(1);
}
do {
bzero(buffer, 256);
printf("Give the numbers now and enter 0 to stop\n");
for (i = 0; i < 256; i++) {
scanf("%d", &buffer[i]);
if (buffer[i] == 0)
break;
}
do {
size++;
i++;
}while (buffer[i] != 0);
n = write(sockfd, buffer, size);
if (n < 0) {
fprintf(stderr, "ERROR: CANNOT WRITE TO SERVER!\n");
exit(1);
}
bzero(buffer2, 13);
n = read(sockfd, buffer2, 13);
if (n < 0) {
fprintf(stderr, "ERROR: CANNOT READ FROM CLIENT!\n");
exit(1);
}
printf("%s\n", buffer2);
printf("Do you want to enter another sequence?\ty (yes) || n (no)\n");
scanf(" %c", &answer);
system("clear");
}while (answer == 'y');
return 0;
}
So the problem is that the server works with different clients (multiple terminals), but will not work with the same client after the first time. I'm new to this whole server-client thing so I'm struggling a bit. Does anyone have an idea?
Thanks in advance.