Sockets programming -- Connection refused

[Alexandros Andreou]

Ti 3exasa, ti 3exasa... To attached arxeio :-)
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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define SUCCESS	0
#define ERROR	(-1)

#define PORT	5820
#define KB	1024
#define BUFSIZE	KB/8

static const char *version =\
 "sysmgr.c:v0.1 Aug 5 2000\n(C) 2000 Alexandros Andreou <andreou at kerveros.gr>\nReleased under GNU GPL.\n";

int main(int argc, char *argv[])
{
	int			sockfd = 0;
	unsigned short int	port = PORT;
	struct hostent		*he;
	struct sockaddr_in	sin;
	FILE			*fp = 0,
				*sockfp = 0;
	char			buf[BUFSIZE];

	printf(version);

	if (argc < 2 || argc > 3) {
		fprintf(stderr, "\n\tUsage: %s <hostname> [<port>]\n", argv[0]);
		exit(ERROR);
	}

	if (argc == 3)
		port = (unsigned short int)strtol(argv[2], NULL, 10);
	
	if ((he = gethostbyname(argv[1])) == NULL) {
		perror("sysmgr.c: gethostbyname()");
		exit(ERROR);
	}
	
	sin.sin_family = AF_INET;
	sin.sin_port = port;
	sin.sin_addr = *((struct in_addr *)he->h_addr);
	bzero(&sin.sin_zero, 8);
	
	bzero(&buf, BUFSIZE);

	if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == ERROR) {
		perror("sysmgr.c: socket()");
		exit(ERROR);
	}
	
	printf("Trying to connect to %s (%s) on port %d...\n", argv[1], inet_ntoa(sin.sin_addr), sin.sin_port);
	if (connect(sockfd, (struct sockaddr *)&sin, sizeof(sin)) == ERROR) {
		perror("sysmgr.c: connect()");
		exit(ERROR);
	}
	
	if ((fp = fdopen((int)stdin, "r")) == NULL) {
		perror("sysmgr.c: fdopen(stdin)");
		exit(ERROR);
	}
	
	if ((fp = fdopen(sockfd, "r")) == NULL) {
		perror("sysmgr.c: fdopen(sockfd)");
		exit(ERROR);
	}
	
	while (fgets(buf, BUFSIZE, fp) != NULL) {
		if (!strncasecmp("QUIT", buf, strlen(buf))) {
			fputs(buf, sockfp);
			break;
		} else
			fputs(buf, sockfp);
	}
		
	fclose(sockfp);
	return (SUCCESS);
}