client_ex.c

#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>
#include <arpa/inet.h>

#define MAXDATASIZE 256 // max number of bytes we can get at once

// get sockaddr, IPv4 or IPv6:
void *get_in_addr(struct sockaddr *sa)
{
	if (sa->sa_family == AF_INET) {
		return &(((struct sockaddr_in*)sa)->sin_addr);
	}
	return &(((struct sockaddr_in6*)sa)->sin6_addr);
}

int main(int argc, char *argv[])
{
	int sockfd, numbytes;
	char buf[MAXDATASIZE];
	struct addrinfo hints, *servinfo, *p;
	int rv;
	char s[INET6_ADDRSTRLEN];
	char *port;	

	port = argv[2];
	memset(&hints, 0, sizeof hints);
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;
	if ((rv = getaddrinfo(argv[1], port, &hints, &servinfo)) != 0) {
		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv));
		return 1;
	}

	// loop through all the results and connect to the first we can
	for(p = servinfo; p != NULL; p = p->ai_next) {
		if ((sockfd = socket(p->ai_family, p->ai_socktype,p->ai_protocol)) == -1) {
			perror("client: socket");
			continue;
		}
		if (connect(sockfd, p->ai_addr, p->ai_addrlen) == -1) {
			close(sockfd);
			perror("client: connect");
			continue;
		}
		break;
	}
	
	if (p == NULL) {
		fprintf(stderr, "client: failed to connect\n");
		return 2;
	}

	inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr),s, sizeof s);
	printf("client: connecting to %s\n", s);
	freeaddrinfo(servinfo); // all done with this structure

	send(sockfd, "GET / \r\n",8,0);
	while(1){
		memset(buf,0,MAXDATASIZE);
		if ((numbytes = recv(sockfd, buf, MAXDATASIZE-1, 0)) == -1) {	
			perror("recv");
			exit(1);
		}
		printf("%s",buf);

	}

	close(sockfd);
	return 0;
}