Notes

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

#define PORT 3490
#define MAXSIZE 1024

int main(int argc, char *argv[])
{
struct sockaddr_in server_info;
struct hostent *he;
int socket_fd,num;
char buffer[1024];

char buff[1024];

if (argc != 2) {
fprintf(stderr, "Usage: client hostnamen");
exit(1);
}

if ((he = gethostbyname(argv[1]))==NULL) {
fprintf(stderr, "Cannot get host namen");
exit(1);
}

if ((socket_fd = socket(AF_INET, SOCK_STREAM, 0))== -1) {
fprintf(stderr, "Socket Failure!!n");
exit(1);
}

memset(&server_info, 0, sizeof(server_info));
server_info.sin_family = AF_INET;
server_info.sin_port = htons(PORT);
server_info.sin_addr = *((struct in_addr *)he->h_addr);
if (connect(socket_fd, (struct sockaddr *)&server_info, sizeof(struct sockaddr))<0) {
//fprintf(stderr, "Connection Failuren");
perror("connect");
exit(1);
}

//buffer = "Hello World!! Lets have funn";
//memset(buffer, 0 , sizeof(buffer));
while(1) {
fgets(buffer,MAXSIZE-1,stdin);
if ((send(socket_fd,buffer, strlen(buffer),0))== -1) {
fprintf(stderr, "Failure Sending Messagen");
close(socket_fd);
exit(1);
}
else {
printf("Message being sent: %sn",buffer);
}
}

/*if ((num = recv(socket_fd, buff, 1024,0))== -1) {
//fprintf(stderr,"Error in receiving message!!n");
perror("recv");
exit(1);
}
// num = recv(client_fd, buffer, sizeof(buffer),0);
buff[num] = '';
printf("Message received: %snNumber of bytes received: %dn", buff,num);*/
close(socket_fd);

}

















































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

#define PORT 3490
#define BACKLOG 10

int main()
{
struct sockaddr_in server;
struct sockaddr_in dest;
int status,socket_fd, client_fd,num;
socklen_t size;

char buffer[10241];
char *buff;
// memset(buffer,0,sizeof(buffer));
int yes =1;



if ((socket_fd = socket(AF_INET, SOCK_STREAM, 0))== -1) {
fprintf(stderr, "Socket failure!!n");
exit(1);
}

if (setsockopt(socket_fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
perror("setsockopt");
exit(1);
}
memset(&server, 0, sizeof(server));
memset(&dest,0,sizeof(dest));
server.sin_family = AF_INET;
server.sin_port = htons(PORT);
server.sin_addr.s_addr = INADDR_ANY;
if ((bind(socket_fd, (struct sockaddr *)&server, sizeof(struct sockaddr )))== -1) { //sizeof(struct sockaddr)
fprintf(stderr, "Binding Failuren");
exit(1);
}

if ((listen(socket_fd, BACKLOG))== -1){
fprintf(stderr, "Listening Failuren");
exit(1);
}

while(1) {
size = sizeof(struct sockaddr_in);

if ((client_fd = accept(socket_fd, (struct sockaddr *)&dest, &size))==-1) {
//fprintf(stderr,"Accept Failuren");
perror("accept");
exit(1);
}
printf("Server got connection from client %sn", inet_ntoa(dest.sin_addr));
//buffer = "Hello World!! I am networking!!n";

while(1) {
if ((num = recv(client_fd, buffer, 10240,0))== -1) {
//fprintf(stderr,"Error in receiving message!!n");
perror("recv");
exit(1);
}
else if (num == 0) {
printf("Connection closedn");
return 0;
}
// num = recv(client_fd, buffer, sizeof(buffer),0);
buffer[num] = '';
printf("Message received: %sn", buffer);
}

/* buff = "I am communicating with the client!!n";

if ((send(client_fd,buff, strlen(buff),0))== -1) {
fprintf(stderr, "Failure Sending Messagen");
close(client_fd);
exit(1);
}
else {
printf("Message being sent: %snNumber of bytes sent: %dn",buff, strlen(buff));
}*/

close(client_fd);
close(socket_fd);
//return 0;
}
//close(client_fd);
return 0;
}