manual/examples/mkisock.c

   1 /* Internet Socket Example
   2    Copyright (C) 1991-2022 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
  23 int
  24 make_socket (uint16_t port)
  25 {
  26   int sock;
  27   struct sockaddr_in name;
  28
  29   /* Create the socket. */
  30   sock = socket (PF_INET, SOCK_STREAM, 0);
  31   if (sock < 0)
  32     {
  33       perror ("socket");
  34       exit (EXIT_FAILURE);
  35     }
  36
  37   /* Give the socket a name. */
  38   name.sin_family = AF_INET;
  39   name.sin_port = htons (port);
  40   name.sin_addr.s_addr = htonl (INADDR_ANY);
  41   if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0)
  42     {
  43       perror ("bind");
  44       exit (EXIT_FAILURE);
  45     }
  46
  47   return sock;
  48 }