communication between windows client and linux server? - c

Question

I am performing communication between client(windows) and server(linux RT) in c. I have written a client code for windows operating system (one laptop) and server code for linux operating system (another laptop). I am connecting the both laptop via ethernet cable and configured them on the same subnet.
SERVER.c : Linux
#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#define BUFLEN 512
#define PORT 9930
void err(char *str)
{
perror(str);
exit(1);
}
int main(void)
{
struct sockaddr_in my_addr, cli_addr;
int sockfd, i;
socklen_t slen=sizeof(cli_addr);
char buf[BUFLEN];
if ((sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
err("socket");
else
printf("Server : Socket() successful\n");
bzero(&my_addr, sizeof(my_addr));
my_addr.sin_family = AF_INET;
my_addr.sin_port = htons(PORT);
my_addr.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(sockfd, (struct sockaddr* ) &my_addr, sizeof(my_addr))==-1)
err("bind");
else
printf("Server : bind() successful\n");
while(1)
{
if (recvfrom(sockfd, buf, BUFLEN, 0, (struct sockaddr*)&cli_addr,
&slen)==-1)
err("recvfrom()");
printf("Received packet from %s:%d\nData: %s\n\n",
inet_ntoa(cli_addr.sin_addr), ntohs(cli_addr.sin_port), buf);
}
close(sockfd);
return 0;
}
CLIENT.c - windows
#pragma comment(lib, "Ws2_32.lib")
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <time.h>
#include <winsock.h>
#include <io.h>
#define BUFLEN 512
#define PORT 9930
void err(char *str)
{
perror(str);
exit(1);
}
int main(void)
{
struct sockaddr_in my_addr, cli_addr;
int sockfd, i;
socklen_t slen=sizeof(cli_addr);
char buf[BUFLEN];
WORD wVersionRequested;
WSADATA wsaData;
printf("Initializing Winsock\n");
wVersionRequested = MAKEWORD (1, 1);
if (WSAStartup (wVersionRequested, &wsaData) != 0){
printf("Winsock initialised failed \n");
} else {
printf("Initialised\n");
if ((sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
err("socket");
bzero(&serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_port = htons(PORT);
if (inet_aton(argv[1], &serv_addr.sin_addr)==0)
{
fprintf(stderr, "inet_aton() failed\n");
exit(1);
}
while(1)
{
printf("\nEnter data to send(Type exit and press enter to exit) : ");
scanf("%[^\n]",buf);
getchar();
if(strcmp(buf,"exit") == 0)
exit(0);
if (sendto(sockfd, buf, BUFLEN, 0, (struct sockaddr*)&serv_addr, slen)==-1)
err("sendto()");
}
close(sockfd);
return 0;
}
My question :
Is it possible to perform communication like this ??
Do I want to take specific measures for doing this ??
Please give ideas regarding this ?

Answer 1

You can connect two systems directly (via ethernet cable), but typically you must use a special cable for that: it is called a "crossover cable". Otherwise no connection is possible.
Newer network controllers implement a detection for this kind of setup, so it might be possible to use a standard cable for this setup, but this depends on the network controllers build into the two systems. You will have to try or consult the documentation.
Also it migh be that you have to select some special configuration on the MS-Windows side (inside the network adapter configuration) for this to work. I experienced communication problems with the standard setup a few times. You can consult google for those settings.