client.c

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#define DATA "Hello World of socket"

int main (int argc, char *argv[])
{
	int sock;
	struct sockaddr_in server;
	struct hostent *hp;
	char buff[1024];
	
	sock = socket (AF_INET, SOCK_STREAM, 0);
	if(sock < 0)
	{
		perror("socket failed");
		exit(1);
	}
	
	server.sin_family = AF_INET;
	hp = gethostbyname(argv[1]);
	if(hp == 0)
	{
		perror("gethostbyname failed");
		close(sock);
		exit(1);
	}
	
	memcpy(&server.sin_addr, hp->h_addr, hp->h_length);
	server.sin_port = htons(1026);
	
	if(connect(sock, (struct sockaddr *) &server, sizeof (server))< 0)
	{
		perror("connect failed");
		close(sock);
		exit(1);
	}
	
	if(send(sock, DATA, sizeof(DATA), 0) < 0)
	{
		perror("sent failed");
		close(sock);
		exit(1);
	}
	
	printf("Sent %s\n", DATA);
	close(sock);
	
	return 0;
}