1  /* Internet Socket Example using sockaddr_in.
       2     Copyright (C) 1991-2023 Free Software Foundation, Inc.
       3  
       4     This program is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU General Public License
       6     as published by the Free Software Foundation; either version 2
       7     of the License, or (at your option) any later version.
       8  
       9     This program is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program; if not, see <https://www.gnu.org/licenses/>.
      16  */
      17  
      18  #include <stdio.h>
      19  #include <stdlib.h>
      20  #include <sys/socket.h>
      21  #include <netinet/in.h>
      22  #include <netdb.h>
      23  
      24  void
      25  init_sockaddr (struct sockaddr_in *name,
      26  	       const char *hostname,
      27  	       uint16_t port)
      28  {
      29    struct hostent *hostinfo;
      30  
      31    name->sin_family = AF_INET;
      32    name->sin_port = htons (port);
      33    hostinfo = gethostbyname (hostname);
      34    if (hostinfo == NULL)
      35      {
      36        fprintf (stderr, "Unknown host %s.\n", hostname);
      37        exit (EXIT_FAILURE);
      38      }
      39    name->sin_addr = *(struct in_addr *) hostinfo->h_addr;
      40  }