1 /* Create socket with an unspecified address family for use with ioctl.
2 Copyright (C) 1999-2021 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <errno.h>
20 #include <sys/socket.h>
21
22 /* Return a socket of any type. The socket can be used in subsequent
23 ioctl calls to talk to the kernel. */
24 int
__opensock(void)25 __opensock (void)
26 {
27 /* SOCK_DGRAM is supported by all address families. */
28 int type = SOCK_DGRAM | SOCK_CLOEXEC;
29 int fd;
30
31 fd = __socket (AF_UNIX, type, 0);
32 if (fd >= 0)
33 return fd;
34 fd = __socket (AF_INET, type, 0);
35 if (fd >= 0)
36 return fd;
37 fd = __socket (AF_INET6, type, 0);
38 if (fd >= 0)
39 return fd;
40 __set_errno (ENOENT);
41 return fd;
42 }
43