/* socket Internet de type datagramme */
/* gcc rec_UDP.c -o rec_UDP -lsocket –lnsl */

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

#define NUM_PORT_REC		9001

main(int argc, char *argv[])
{  int sock, lg_max, lg_rec, lg_nom_em;
   struct sockaddr_in nom, nom_em;
   char message[100];

   /* construction du nom externe du socket local */ 
   
   if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
     {
      printf ("erreur creation socket\n");
      exit (1);
     }  

   /* association nom interne - nom externe socket local */ 

   nom.sin_family = AF_INET;
   nom.sin_port = NUM_PORT_REC;
   nom.sin_addr.s_addr = INADDR_ANY;

   if (bind(sock, (struct sockaddr *)&nom, sizeof(nom)) == -1)
     {
      printf ("erreur bind\n");
      exit(1);
     }  
   
   /* reception des messages */ 

    lg_max = 10;
    lg_rec = 0;
    lg_nom_em = sizeof(nom_em);

    for (;;) 
      {
       printf ("\n*** Attente Message ***\n\n");
       if ((lg_rec = recvfrom(sock,message,lg_max,0,(struct sockaddr *)&nom_em,&lg_nom_em)) > 0)
         {
          printf ("taille du message recu : %d\n", lg_rec);
          message[lg_rec]='\0';
          printf ("message recu : %s \n\n", message);
         }
       else
         {
          printf ("erreur en reception");
          exit(1);
         }          
      }
}

 
Corrections TCP