File: /usr/include/sys/socket.h
1 /* Declarations of socket constants, types, and functions.
2 Copyright (C) 1991,92,1994-1999,2000,2001 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 Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 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 Library General Public License for more details.
14
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
19
20 #ifndef _SYS_SOCKET_H
21 #define _SYS_SOCKET_H 1
22
23 #include <features.h>
24
25 __BEGIN_DECLS
26
27 #include <sys/uio.h>
28 #define __need_size_t
29 #include <stddef.h>
30
31
32 /* This operating system-specific header file defines the SOCK_*, PF_*,
33 AF_*, MSG_*, SOL_*, and SO_* constants, and the `struct sockaddr',
34 `struct msghdr', and `struct linger' types. */
35 #include <bits/socket.h>
36
37 #ifdef __USE_BSD
38 /* This is the 4.3 BSD `struct sockaddr' format, which is used as wire
39 format in the grotty old 4.3 `talk' protocol. */
40 struct osockaddr
41 {
42 unsigned short int sa_family;
43 unsigned char sa_data[14];
44 };
45 #endif
46
47 /* The following constants should be used for the second parameter of
48 `shutdown'. */
49 enum
50 {
51 SHUT_RD = 0, /* No more receptions. */
52 #define SHUT_RD SHUT_RD
53 SHUT_WR, /* No more transmissions. */
54 #define SHUT_WR SHUT_WR
55 SHUT_RDWR /* No more receptions or transmissions. */
56 #define SHUT_RDWR SHUT_RDWR
57 };
58
59 /* This is the type we use for generic socket address arguments.
60
61 With GCC 2.7 and later, the funky union causes redeclarations or
62 uses with any of the listed types to be allowed without complaint.
63 G++ 2.7 does not support transparent unions so there we want the
64 old-style declaration, too. */
65 #if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU
66 # define __SOCKADDR_ARG struct sockaddr *__restrict
67 # define __CONST_SOCKADDR_ARG __const struct sockaddr *
68 #else
69 /* Add more `struct sockaddr_AF' types here as necessary.
70 These are all the ones I found on NetBSD and Linux. */
71 # define __SOCKADDR_ALLTYPES \
72 __SOCKADDR_ONETYPE (sockaddr) \
73 __SOCKADDR_ONETYPE (sockaddr_at) \
74 __SOCKADDR_ONETYPE (sockaddr_ax25) \
75 __SOCKADDR_ONETYPE (sockaddr_dl) \
76 __SOCKADDR_ONETYPE (sockaddr_eon) \
77 __SOCKADDR_ONETYPE (sockaddr_in) \
78 __SOCKADDR_ONETYPE (sockaddr_in6) \
79 __SOCKADDR_ONETYPE (sockaddr_inarp) \
80 __SOCKADDR_ONETYPE (sockaddr_ipx) \
81 __SOCKADDR_ONETYPE (sockaddr_iso) \
82 __SOCKADDR_ONETYPE (sockaddr_ns) \
83 __SOCKADDR_ONETYPE (sockaddr_un) \
84 __SOCKADDR_ONETYPE (sockaddr_x25)
85
86 # define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__;
87 typedef union { __SOCKADDR_ALLTYPES
88 } __SOCKADDR_ARG __attribute__ ((__transparent_union__));
89 # undef __SOCKADDR_ONETYPE
90 # define __SOCKADDR_ONETYPE(type) __const struct type *__restrict __##type##__;
91 typedef union { __SOCKADDR_ALLTYPES
92 } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__));
93 # undef __SOCKADDR_ONETYPE
94 #endif
95
96
97 /* Create a new socket of type TYPE in domain DOMAIN, using
98 protocol PROTOCOL. If PROTOCOL is zero, one is chosen automatically.
99 Returns a file descriptor for the new socket, or -1 for errors. */
100 extern int socket (int __domain, int __type, int __protocol) __THROW;
101
102 /* Create two new sockets, of type TYPE in domain DOMAIN and using
103 protocol PROTOCOL, which are connected to each other, and put file
104 descriptors for them in FDS[0] and FDS[1]. If PROTOCOL is zero,
105 one will be chosen automatically. Returns 0 on success, -1 for errors. */
106 extern int socketpair (int __domain, int __type, int __protocol,
107 int __fds[2]) __THROW;
108
109 /* Give the socket FD the local address ADDR (which is LEN bytes long). */
110 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
111 __THROW;
112
113 /* Put the local address of FD into *ADDR and its length in *LEN. */
114 extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
115 socklen_t *__restrict __len) __THROW;
116
117 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
118 For connectionless socket types, just set the default address to send to
119 and the only address from which to accept transmissions.
120 Return 0 on success, -1 for errors. */
121 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
122 __THROW;
123
124 /* Put the address of the peer connected to socket FD into *ADDR
125 (which is *LEN bytes long), and its actual length into *LEN. */
126 extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
127 socklen_t *__restrict __len) __THROW;
128
129
130 /* Send N bytes of BUF to socket FD. Returns the number sent or -1. */
131 extern int send (int __fd, __const void *__buf, size_t __n, int __flags)
132 __THROW;
133
134 /* Read N bytes into BUF from socket FD.
135 Returns the number read or -1 for errors. */
136 extern int recv (int __fd, void *__buf, size_t __n, int __flags)
137 __THROW;
138
139 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
140 ADDR_LEN bytes long). Returns the number sent, or -1 for errors. */
141 extern int sendto (int __fd, __const void *__buf, size_t __n,
142 int __flags, __CONST_SOCKADDR_ARG __addr,
143 socklen_t __addr_len) __THROW;
144
145 /* Read N bytes into BUF through socket FD.
146 If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
147 the sender, and store the actual size of the address in *ADDR_LEN.
148 Returns the number of bytes read or -1 for errors. */
149 extern int recvfrom (int __fd, void *__restrict __buf, size_t __n, int __flags,
150 __SOCKADDR_ARG __addr, socklen_t *__restrict __addr_len)
151 __THROW;
152
153
154 /* Send a message described MESSAGE on socket FD.
155 Returns the number of bytes sent, or -1 for errors. */
156 extern int sendmsg (int __fd, __const struct msghdr *__message, int __flags)
157 __THROW;
158
159 /* Receive a message as described by MESSAGE from socket FD.
160 Returns the number of bytes read or -1 for errors. */
161 extern int recvmsg (int __fd, struct msghdr *__message, int __flags)
162 __THROW;
163
164
165 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
166 into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
167 actual length. Returns 0 on success, -1 for errors. */
168 extern int getsockopt (int __fd, int __level, int __optname,
169 void *__restrict __optval,
170 socklen_t *__restrict __optlen) __THROW;
171
172 /* Set socket FD's option OPTNAME at protocol level LEVEL
173 to *OPTVAL (which is OPTLEN bytes long).
174 Returns 0 on success, -1 for errors. */
175 extern int setsockopt (int __fd, int __level, int __optname,
176 __const void *__optval, socklen_t __optlen) __THROW;
177
178
179 /* Prepare to accept connections on socket FD.
180 N connection requests will be queued before further requests are refused.
181 Returns 0 on success, -1 for errors. */
182 extern int listen (int __fd, int __n) __THROW;
183
184 /* Await a connection on socket FD.
185 When a connection arrives, open a new socket to communicate with it,
186 set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
187 peer and *ADDR_LEN to the address's actual length, and return the
188 new socket's descriptor, or -1 for errors. */
189 extern int accept (int __fd, __SOCKADDR_ARG __addr,
190 socklen_t *__restrict __addr_len)
191 __THROW;
192
193 /* Shut down all or part of the connection open on socket FD.
194 HOW determines what to shut down:
195 SHUT_RD = No more receptions;
196 SHUT_WR = No more transmissions;
197 SHUT_RDWR = No more receptions or transmissions.
198 Returns 0 on success, -1 for errors. */
199 extern int shutdown (int __fd, int __how) __THROW;
200
201
202 #ifdef __USE_MISC
203 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
204 returns 1 if FD is open on an object of the indicated type, 0 if not,
205 or -1 for errors (setting errno). */
206 extern int isfdtype (int __fd, int __fdtype) __THROW;
207 #endif
208
209 __END_DECLS
210
211 #endif /* sys/socket.h */
212