client1.c

linux 下socket 客户端和服务器

#include <errno.h>
#include "creerSocket.h"
#include <string.h>
#include <netdb.h>

#define BUFF_SIZE 256

void g(int desc, int i) {
  int n;
  char buff[BUFF_SIZE];
  sprintf(buff, "%d", i);
  if ( write(desc, buff, 10) == -1 ) { perror("Erreur d'ecriture"); exit(1); };
  n = read(desc, buff, BUFF_SIZE);
  if ( n == -1 ) { perror("Erreur de lecture"); exit(1); }
  buff[n] = '\0';
  printf("%s", buff);
}

struct sockaddr_in adr_ser, adr_cli;

int main(int argc, char **argv) {
  int port, sock;
  struct hostent *hp;
  if (argc < 4) { 
    fprintf(stderr, "usage: %s machine port i\n",argv[0]); exit(2); 
  }
  if ( (hp = gethostbyname(argv[1])) == NULL ) {
    fprintf(stderr, "machine %s inconnue\n",argv[1]); exit(2); 
  }
  port = 0;
  if ( (sock = creerSocket(SOCK_STREAM, port, &adr_cli)) == -1 ) {
    fprintf(stderr, "Creation de socket impossible\n"); exit(2);
  }

  adr_ser.sin_family = AF_INET; 
  adr_ser.sin_port = htons(atoi(argv[2]));
  memcpy(&adr_ser.sin_addr.s_addr, hp->h_addr, hp->h_length);
  if (connect(sock, (struct sockaddr *)&adr_ser, sizeof(adr_ser)) == -1) {
    perror("conect"); exit(2);
  }
  printf("Connexion acceptee\n");
  g(sock, atoi(argv[3]));
}