Hi,
I am newbie to network programming in C. I want to implement a file transfer program in C on a Linux environment .
I am sending the file name to the server and tries to print it on the server. But the server doesn't print it. I think I am not using the send function well... Can anybody helps me in this regard? the code is below...
1. client code
//Including necessary header files
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define MAXDATASIZE 500 // The Size Of Data Buffer
int main(int argc, char *argv[])
{
//Declaring some variables
int sockfd;
int numbytes;
int port;
char buf[MAXDATASIZE];
uint16_t length;
char file_name[10];
//Declaring Address Structures
struct hostent *he;
struct sockaddr_in serverAddress;
//Checking the Command Line Arguments
if (argc != 3) {
fprintf(stderr,"usage: client hostname\n");
exit(1);
}
//Get The IP Address of the Server From Command Line Arguments
serverAddress.sin_addr.s_addr = inet_addr(argv[1]);
he=gethostbyaddr((char *) &serverAddress.sin_addr.s_addr,sizeof(serverAddress.sin_addr.s_addr),AF_INET);
//Get The Server Port From The Command Line Arguments
port=atoi(argv[2]);
//Creating A Socket
if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
//Filling the Server Address Structure
serverAddress.sin_family = AF_INET;
serverAddress.sin_port = htons(port);
serverAddress.sin_addr = *((struct in_addr *)he->h_addr);
//Setting The Whole Structure To Zero
memset(serverAddress.sin_zero, '\0', sizeof serverAddress.sin_zero);
//Connecting To The Server
if (connect(sockfd, (struct sockaddr *)&serverAddress,sizeof (serverAddress)) == -1) {
perror("connect");
exit(1);
}
//Receiving Some Data From Server
if ((numbytes=recv(sockfd, buf, MAXDATASIZE-1, 0)) == -1) {
perror("recv");
exit(1);
}
//Terminating The Received Data With Null
buf[numbytes] = '\0';
//Printing The Received Data
printf(" %s",buf);
//Acquring the file name from console
printf("Enter the file name: ");
fgets(file_name, 10, stdin);
bzero(&buf,sizeof(buf));
sprintf(buf,"%s",file_name);
send(sockfd,buf,10,0);
//Closing The Socket
close(sockfd);
return 0;
}2. Server Code
//Including necessary header files
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#define SERVER_PORT 9999 // The Well Know Server Port
#define BACKLOG 10 // Maximum Pending Connections
#define MAX_SIZE 500 // The Size Of Data Buffer
int main(void)
{
//Declaring some socket handlers
int listenSocket;
int activeSocket;
//Declaring Some Error Checking Bits
int numberOfBytes;
int socketOption;
int bindCheck;
int listenCheck;
int sendCheck;
int yes=1;
//Declaring some size variables
char buffer[MAX_SIZE];
char welcomeMessage[50];
socklen_t client_size;
//Declaring Address Structures for Client and Server
struct sockaddr_in serverAddress;
struct sockaddr_in clientAddress;
//Opening a Socket in Passive Mode
listenSocket = socket(AF_INET, SOCK_STREAM, 0);
//Doing Error Checking
if(listenSocket==-1){
perror("socket");
exit(1);
}
//Setting the Socket Option
socketOption=setsockopt(listenSocket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int));
//Doing Error Checking
if(socketOption==-1){
perror("setsockopt");
exit(1);
}
//Filling the Server Adress Structure
serverAddress.sin_family = AF_INET;
serverAddress.sin_port = htons(SERVER_PORT);
serverAddress.sin_addr.s_addr = INADDR_ANY;
//Setting the Whole Structure To Zero
memset(serverAddress.sin_zero, '\0', sizeof (serverAddress.sin_zero));
//Binding The Listening Socket to the server well known port
bindCheck=bind(listenSocket, (struct sockaddr *)&serverAddress, sizeof (serverAddress));
//Doing Error Checking
if(bindCheck==-1){
perror("bind");
exit(1);
}
//Start Litsening for Connections on The Listening Socket
listenCheck=listen(listenSocket, BACKLOG);
//Doing Error Checking
if(listenCheck==-1){
perror("listen");
exit(1);
}
//The Infinite For Loop Starts
for(;;) {
//Size of The incoming Client Adress Structure
client_size = sizeof (clientAddress);
//Accepting the incoming connection from client and creating another socket for it
activeSocket = accept(listenSocket, (struct sockaddr *)&clientAddress, &client_size);
//Doing Error Checking
if(activeSocket==-1){
perror("accept");
continue;
}
/* printf("server: got connection from %s\n %d\n", \
inet_ntoa(clientAddress.sin_addr),activeSocket);*/
//Preparing Welcome Message To The Client
sprintf(welcomeMessage,"Welcome User: IP Address-%s Port-%d\n",inet_ntoa (clientAddress.sin_addr),activeSocket);
//Sending A Message To Client
sendCheck=send(activeSocket, welcomeMessage, MAX_SIZE, MSG_DONTWAIT);
//Doing Error Checking
if(sendCheck==-1){
perror("send");
}
//Receving Some Text from Client
numberOfBytes=recv(activeSocket, buffer,MAX_SIZE, 0);
//Doing Error Checking
if(numberOfBytes==-1)
{
perror("recv");
exit(1);
}
//Terminating The Received Data with Null
buffer[numberOfBytes] = '\0';
//Printing The Received Data on Console
printf("Received: %s",buffer);
}
//Closing the Socket which communicating with Client
close(activeSocket);
return 0;
}Thanks
