| getsockopt.2 (123814) | getsockopt.2 (131504) |
|---|---|
| 1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)getsockopt.2 8.4 (Berkeley) 5/2/95 | 1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)getsockopt.2 8.4 (Berkeley) 5/2/95 |
| 33.\" $FreeBSD: head/lib/libc/sys/getsockopt.2 123814 2003-12-24 18:52:41Z alfred $ | 33.\" $FreeBSD: head/lib/libc/sys/getsockopt.2 131504 2004-07-02 23:52:20Z ru $ |
| 34.\" 35.Dd May 2, 1995 36.Dt GETSOCKOPT 2 37.Os 38.Sh NAME 39.Nm getsockopt , 40.Nm setsockopt 41.Nd get and set options on sockets --- 9 unchanged lines hidden (view full) --- 51.Sh DESCRIPTION 52The 53.Fn getsockopt 54and 55.Fn setsockopt 56system calls 57manipulate the 58.Em options | 34.\" 35.Dd May 2, 1995 36.Dt GETSOCKOPT 2 37.Os 38.Sh NAME 39.Nm getsockopt , 40.Nm setsockopt 41.Nd get and set options on sockets --- 9 unchanged lines hidden (view full) --- 51.Sh DESCRIPTION 52The 53.Fn getsockopt 54and 55.Fn setsockopt 56system calls 57manipulate the 58.Em options |
| 59associated with a socket. Options may exist at multiple | 59associated with a socket. 60Options may exist at multiple |
| 60protocol levels; they are always present at the uppermost 61.Dq socket 62level. 63.Pp 64When manipulating socket options the level at which the 65option resides and the name of the option must be specified. 66To manipulate options at the socket level, 67.Fa level 68is specified as 69.Dv SOL_SOCKET . 70To manipulate options at any 71other level the protocol number of the appropriate protocol | 61protocol levels; they are always present at the uppermost 62.Dq socket 63level. 64.Pp 65When manipulating socket options the level at which the 66option resides and the name of the option must be specified. 67To manipulate options at the socket level, 68.Fa level 69is specified as 70.Dv SOL_SOCKET . 71To manipulate options at any 72other level the protocol number of the appropriate protocol |
| 72controlling the option is supplied. For example, | 73controlling the option is supplied. 74For example, |
| 73to indicate that an option is to be interpreted by the 74.Tn TCP 75protocol, 76.Fa level 77should be set to the protocol number of 78.Tn TCP ; 79see 80.Xr getprotoent 3 . 81.Pp 82The 83.Fa optval 84and 85.Fa optlen 86arguments 87are used to access option values for 88.Fn setsockopt . 89For 90.Fn getsockopt 91they identify a buffer in which the value for the | 75to indicate that an option is to be interpreted by the 76.Tn TCP 77protocol, 78.Fa level 79should be set to the protocol number of 80.Tn TCP ; 81see 82.Xr getprotoent 3 . 83.Pp 84The 85.Fa optval 86and 87.Fa optlen 88arguments 89are used to access option values for 90.Fn setsockopt . 91For 92.Fn getsockopt 93they identify a buffer in which the value for the |
| 92requested option(s) are to be returned. For | 94requested option(s) are to be returned. 95For |
| 93.Fn getsockopt , 94.Fa optlen 95is a value-result argument, initially containing the 96size of the buffer pointed to by 97.Fa optval , 98and modified on return to indicate the actual size of | 96.Fn getsockopt , 97.Fa optlen 98is a value-result argument, initially containing the 99size of the buffer pointed to by 100.Fa optval , 101and modified on return to indicate the actual size of |
| 99the value returned. If no option value is | 102the value returned. 103If no option value is |
| 100to be supplied or returned, 101.Fa optval 102may be NULL. 103.Pp 104The 105.Fa optname 106argument 107and any specified options are passed uninterpreted to the appropriate --- 66 unchanged lines hidden (view full) --- 174allows completely duplicate bindings by multiple processes 175if they all set 176.Dv SO_REUSEPORT 177before binding the port. 178This option permits multiple instances of a program to each 179receive UDP/IP multicast or broadcast datagrams destined for the bound port. 180.Dv SO_KEEPALIVE 181enables the | 104to be supplied or returned, 105.Fa optval 106may be NULL. 107.Pp 108The 109.Fa optname 110argument 111and any specified options are passed uninterpreted to the appropriate --- 66 unchanged lines hidden (view full) --- 178allows completely duplicate bindings by multiple processes 179if they all set 180.Dv SO_REUSEPORT 181before binding the port. 182This option permits multiple instances of a program to each 183receive UDP/IP multicast or broadcast datagrams destined for the bound port. 184.Dv SO_KEEPALIVE 185enables the |
| 182periodic transmission of messages on a connected socket. Should the | 186periodic transmission of messages on a connected socket. 187Should the |
| 183connected party fail to respond to these messages, the connection is 184considered broken and processes using the socket are notified via a 185.Dv SIGPIPE 186signal when attempting to send data. 187.Dv SO_DONTROUTE 188indicates that outgoing messages should | 188connected party fail to respond to these messages, the connection is 189considered broken and processes using the socket are notified via a 190.Dv SIGPIPE 191signal when attempting to send data. 192.Dv SO_DONTROUTE 193indicates that outgoing messages should |
| 189bypass the standard routing facilities. Instead, messages are directed | 194bypass the standard routing facilities. 195Instead, messages are directed |
| 190to the appropriate network interface according to the network portion 191of the destination address. 192.Pp 193.Dv SO_LINGER 194controls the action taken when unsent messages 195are queued on socket and a 196.Xr close 2 197is performed. --- 214 unchanged lines hidden --- | 196to the appropriate network interface according to the network portion 197of the destination address. 198.Pp 199.Dv SO_LINGER 200controls the action taken when unsent messages 201are queued on socket and a 202.Xr close 2 203is performed. --- 214 unchanged lines hidden --- |