SQUELETTE DE COMMUNICATION PAR SOCKET EN MODE CONNECTÉ POUR LINUX

//
// Fichier myinet.h
//

#define MYCORPS 16
struct mymsg {
	uint32_t entete;
	char corps[MYCORPS];
};

#define BACKLOG 64

//
// Fichier afinettcpe.c
//

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include "myinet.h"

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

	struct hostent *phost;
	int sockfd;
	struct sockaddr_in serv_addr;
	int cpt = 0;
	struct mymsg msg;
	int ret_send;
	if (argc < 3) {
		fprintf(stderr, "USAGE : afinettcpe machine_cible port_cible\n");
		exit (EXIT_FAILURE);
	}
	phost = gethostbyname(argv[1]);
	if (phost == NULL) { 
		fprintf(stderr, "Incident gethostbyname(\"%s\"p)", argv[1]);
	}

	sockfd = socket(AF_INET, SOCK_STREAM, 0);
	if (sockfd == -1) { perror("socket()"); exit (EXIT_FAILURE); }

	/* pour le client un bind est fait automatiquement lors du connect() */
	memset(&serv_addr, '\0', sizeof(serv_addr));
	serv_addr.sin_family = AF_INET;
	serv_addr.sin_port = htons((uint16_t)atoi(argv[2]));
	memcpy(&serv_addr.sin_addr, phost->h_addr, phost->h_length);
	if (connect (sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1 ) { perror ("connect()"); exit(EXIT_FAILURE); }

	while (++cpt) {
		msg.entete = htonl((uint32_t)cpt);
		strcpy (msg.corps, "Pour voir");
		ret_send = send(sockfd, &msg, sizeof(msg), 0);
		if (ret_send == -1) { perror ("send()\n"); exit(EXIT_FAILURE); }
		sleep(1);
	}  
}

//
// Fichier afinettcpr.c
//

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include "myinet.h"

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

	int sockfd, socksrvfd;
	struct sockaddr_in my_addr, name, from;
	int fromlen;
	struct mymsg msg;
	int ret_recv;
	int cpt = 0, i, j;

	if (argc < 2) { fprintf(stderr, "Usage : afinettcpr port_reception\n"); exit (EXIT_FAILURE);}

	/* Acquisition d'un descripteur de socket. */
	sockfd = socket(AF_INET, SOCK_STREAM, 0);
	if (sockfd == -1) { perror("socket()"); exit (EXIT_FAILURE); }

	/* assignation d'une adresse à la socket */
	memset(&my_addr, '\0', sizeof(my_addr));
	my_addr.sin_family = AF_INET;
	my_addr.sin_port = htons((uint16_t)atoi(argv[1]));
	my_addr.sin_addr.s_addr = htonl(INADDR_ANY);
	if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(my_addr)) == -1) { perror("bind()"); exit(EXIT_FAILURE); }
	if (listen(sockfd, BACKLOG) == -1) { perror("listen()"); exit(EXIT_FAILURE); }

	/* socket de service */
	fromlen = sizeof(from);
	memset(&from, '\0', sizeof(from));

	ecoute:
	socksrvfd = accept(sockfd, (struct sockaddr*)&from, &fromlen);
	if (socksrvfd == -1) { perror ("accept()"); exit(EXIT_FAILURE); }
	/* qui a émis */
	printf("fromlen : %d ", fromlen);
	printf("sin_family : %d ", from.sin_family);
	printf("sin_port : %d ", from.sin_port);
	printf("sin_addr : %d ", inet_ntoa(from.sin_addr));
	printf("\n");
	printf("Entrée dans la boucle de reception\n");
	while (++cpt) {
		/* lecture d'un message */
		ret_recv = recv(socksrvfd, &msg, sizeof(msg), 0);
		if (ret_recv == 0) goto ecoute;
		if (ret_recv == -1) { perror("recv()"); exit (EXIT_FAILURE); }
		/* message reçu */
		printf("cpt_serveur %d : ", cpt);
		printf("message %d - %s ",(int)ntohl(msg.entete), msg.corps);
		printf("\n");
	}  
}