#include <sys/types.h>
#include <sys/socket.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/poll.h>
#include <sys/sendfile.h>

#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <time.h>
#include <ctype.h>
#include <netdb.h>

#define ulog(f, a...) fprintf(stderr, f, ##a)
#define ulog_err(f, a...) ulog(f ": %s [%d].\n", ##a, strerror(errno), errno)

int main(int argc, char *argv[])
{
	struct hostent *h;
	int s, err;
	char buf[128];
	struct sockaddr_in sa;
	fd_set rfds;
	struct timeval tv;

	if (argc != 3) {
		ulog("Usage: %s <addr> <port>\n", argv[0]);
		return -1;
	}
	
	h = gethostbyname(argv[1]);
	if (!h) {
		ulog_err("%s: Failed to get address of %s.\n", __func__, argv[1]);
		return -1;
	}

	s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	if (s == -1) {
		ulog_err("%s: Failed to create server socket", __func__);
		return -1;
	}
	
	memcpy(&(sa.sin_addr.s_addr), h->h_addr_list[0], 4);
	sa.sin_port = htons(atoi(argv[2]));
	sa.sin_family = AF_INET;

	if (connect(s, (struct sockaddr *)&sa, sizeof(sa))) {
		ulog_err("%s: Failed to connect to %s:%s", __func__, argv[1], argv[2]);
		return -1;
	}

	do {
		FD_ZERO(&rfds);
		FD_SET(s, &rfds);

		tv.tv_sec = 500;
		tv.tv_usec = 0;

		err = select(s+1, &rfds, NULL, NULL, &tv);
		ulog("select: err: %d, errno: %d.\n", err, errno);

		err = write(s, buf, sizeof(buf));
		ulog("write: err: %d, errno: %d.\n", err, errno);
	} while (err > 0);

	FD_ZERO(&rfds);
	FD_SET(s, &rfds);

	tv.tv_sec = 500;
	tv.tv_usec = 0;

	err = select(s+1, &rfds, NULL, NULL, &tv);

	ulog("on exit: select: err: %d, errno: %d.\n", err, errno);
}