SK - 15.10.2015

############################################################################
###########     PROGRAM 1

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>

#define BUFSIZE 10000

char bufor[BUFSIZE];

char *service = "daytime";
char *protocol = "tcp";

int main (int argc, char** argv) {

    struct sockaddr_in  sck_addr;
    struct hostent      *host_ptr;
    struct protoent     *protocol_ptr;
    struct servent      *service_ptr;

    int sck, odp;

    if (argc < 2) {
        printf ("Podaj nazwę serwera\n");
        exit (EXIT_FAILURE);
    }

    printf ("Usługa %d na %s z serwera %s :\n", service, protocol, argv[1]);
    fflush(stdout);

    if ((host_ptr = gethostbyname (argv[1])) == NULL) {
        perror("Nie znaleziono serwera");
        exit(EXIT_FAILURE);
    }

    if ((protocol_ptr = getprotobyname (protocol)) == NULL) {
        perror ("Nie znaleziono protokołu");
        exit(EXIT_FAILURE);
    }

    if ((service_ptr = getservbyname (service, protocol)) == NULL) {
        perror ("Nie znaleziono uslugi");
        exit(EXIT_FAILURE);
    }

    memset (&sck_addr, 0, sizeof sck_addr);
    sck_addr.sin_family = host_ptr -> h_addrtype;
    memcpy ((char*) &sck_addr.sin_addr, (char*) host_ptr -> h_addr, host_ptr -> h_length);
    sck_addr.sin_port = service_ptr ->s_port;

    if ((sck = socket (PF_INET, SOCK_STREAM, protocol_ptr -> p_proto)) < 0) {
        perror ("Nie można utworzyć gniazdka");
        exit (EXIT_FAILURE);
    }

    if (connect (sck, (struct sockaddr*) &sck_addr, sizeof sck_addr) < 0) {
        perror ("Brak połączenia");
        exit (EXIT_FAILURE);
    }

    while ((odp = read (sck, bufor, BUFSIZE)) > 0)
        write (1, bufor, odp);
    close (sck);

    exit (EXIT_SUCCESS);
}


################################################################################
############   PROGRAM 2

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>

#define BUFSIZE 10000

char bufor[BUFSIZE];

char *service = "echo";
char *protocol = "tcp";

int main (int argc, char** argv) {

    struct sockaddr_in  sck_addr;
    struct hostent      *host_ptr;
    struct protoent     *protocol_ptr;
    struct servent      *service_ptr;

    int sck, odp;
    char message[1000], server_reply[2000];

    if (argc < 2) {
        printf ("Podaj nazwę serwera\n");
        exit (EXIT_FAILURE);
    }

    printf ("Usługa %d na %s z serwera %s :\n", service, protocol, argv[1]);
    fflush(stdout);

    if ((host_ptr = gethostbyname (argv[1])) == NULL) {
        perror("Nie znaleziono serwera");
        exit(EXIT_FAILURE);
    }

    if ((protocol_ptr = getprotobyname (protocol)) == NULL) {
        perror ("Nie znaleziono protokołu");
        exit(EXIT_FAILURE);
    }

    if ((service_ptr = getservbyname (service, protocol)) == NULL) {
        perror ("Nie znaleziono uslugi");
        exit(EXIT_FAILURE);
    }

    memset (&sck_addr, 0, sizeof sck_addr);
    sck_addr.sin_family = host_ptr -> h_addrtype;
    memcpy ((char*) &sck_addr.sin_addr, (char*) host_ptr -> h_addr, host_ptr -> h_length);
    sck_addr.sin_port = service_ptr ->s_port;

    if ((sck = socket (PF_INET, SOCK_STREAM, protocol_ptr -> p_proto)) < 0) {
        perror ("Nie można utworzyć gniazdka");
        exit (EXIT_FAILURE);
    }

    if (connect (sck, (struct sockaddr*) &sck_addr, sizeof sck_addr) < 0) {
        perror ("Brak połączenia");
        exit (EXIT_FAILURE);
    }

    while (1) {
        printf("\nWiadomość przesyłana: ");
        fflush(stdout);
        gets(message);

        if (send(sck, message, strlen(message), 0) < 0) {
            perror ("Nie mozna wyslac");
            exit (EXIT_FAILURE);
        }
        bzero(server_reply, 2000);
        if ( recv(sck, server_reply, 2000, 0) < 0) {
            perror("Nie mozna odebrac");
            exit (EXIT_FAILURE);
        }
        printf("Wiadomość zwracana: ");
        printf(server_reply);
        fflush(stdout);
    }

    close (sck);

    exit (EXIT_SUCCESS);
}