diff options
Diffstat (limited to 'share/man/man4/spp.4')
| -rw-r--r-- | share/man/man4/spp.4 | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/share/man/man4/spp.4 b/share/man/man4/spp.4 new file mode 100644 index 0000000..d749e2e --- /dev/null +++ b/share/man/man4/spp.4 @@ -0,0 +1,191 @@ +.\" Copyright (c) 1985, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)spp.4 8.2 (Berkeley) 4/19/94 +.\" +.Dd April 19, 1994 +.Dt SPP 4 +.Os BSD 4.3 +.Sh NAME +.Nm spp +.Nd Xerox Sequenced Packet Protocol +.Sh SYNOPSIS +.Fd #include <sys/socket.h> +.Fd #include <netns/ns.h> +.Fd #include <netns/sp.h> +.Ft int +.Fn socket AF_NS SOCK_STREAM 0 +.Ft int +.Fn socket AF_NS SOCK_SEQPACKET 0 +.Sh DESCRIPTION +The +.Tn SPP +protocol provides reliable, flow-controlled, two-way +transmission of data. It is a byte-stream protocol used to +support the +.Dv SOCK_STREAM +abstraction. +.Tn SPP +uses the standard +.Tn NS Ns (tm) +address formats. +.Pp +Sockets utilizing the +.Tn SPP +protocol are either +.Dq active +or +.Dq passive . +Active sockets initiate connections to passive +sockets. By default +.Tn SPP +sockets are created active; to create a +passive socket the +.Xr listen 2 +system call must be used +after binding the socket with the +.Xr bind 2 +system call. Only +passive sockets may use the +.Xr accept 2 +call to accept incoming connections. Only active sockets may +use the +.Xr connect 2 +call to initiate connections. +.Pp +Passive sockets may +.Dq underspecify +their location to match +incoming connection requests from multiple networks. This +technique, termed +.Dq wildcard addressing , +allows a single +server to provide service to clients on multiple networks. +To create a socket which listens on all networks, the +.Tn NS +address of all zeroes must be bound. +The +.Tn SPP +port may still be specified +at this time; if the port is not specified the system will assign one. +Once a connection has been established the socket's address is +fixed by the peer entity's location. The address assigned the +socket is the address associated with the network interface +through which packets are being transmitted and received. Normally +this address corresponds to the peer entity's network. +.Pp +If the +.Dv SOCK_SEQPACKET +socket type is specified, +each packet received has the actual 12 byte sequenced packet header +left for the user to inspect: +.Bd -literal -offset indent +struct sphdr { + u_char sp_cc; /* connection control */ +#define SP_EM 0x10 /* end of message */ + u_char sp_dt; /* datastream type */ + u_short sp_sid; + u_short sp_did; + u_short sp_seq; + u_short sp_ack; + u_short sp_alo; +}; +.Ed +.Pp +This facilitates the implementation of higher level Xerox protocols +which make use of the data stream type field and the end of message bit. +Conversely, the user is required to supply a 12 byte header, +the only part of which inspected is the data stream type and end of message +fields. +.Pp +For either socket type, +packets received with the Attention bit sent are interpreted as +out of band data. Data sent with +.Dq send(..., ..., ..., Dv MSG_OOB ) +cause the attention bit to be set. +.Sh DIAGNOSTICS +A socket operation may fail with one of the following errors returned: +.Bl -tag -width [EADDRNOTAVAIL] +.It Bq Er EISCONN +when trying to establish a connection on a socket which +already has one; +.It Bq Er ENOBUFS +when the system runs out of memory for +an internal data structure; +.It Bq Er ETIMEDOUT +when a connection was dropped +due to excessive retransmissions; +.It Bq Er ECONNRESET +when the remote peer +forces the connection to be closed; +.It Bq Er ECONNREFUSED +when the remote +peer actively refuses connection establishment (usually because +no process is listening to the port); +.It Bq Er EADDRINUSE +when an attempt +is made to create a socket with a port which has already been +allocated; +.It Bq Er EADDRNOTAVAIL +when an attempt is made to create a +socket with a network address for which no network interface +exists. +.El +.Sh SOCKET OPTIONS +.Bl -tag -width SO_DEFAULT_HEADERS +.It Dv SO_DEFAULT_HEADERS +when set, this determines the data stream type and whether +the end of message bit is to be set on every ensuing packet. +.It Dv SO_MTU +This specifies the maximum amount of user data in a single packet. +The default is 576 bytes - sizeof(struct spidp). This quantity +affects windowing \- increasing it without increasing the amount +of buffering in the socket will lower the number of unread packets +accepted. Anything larger than the default will not be forwarded +by a bona fide +.Tn XEROX +product internetwork router. +The data argument for the setsockopt call must be +an unsigned short. +.El +.Sh SEE ALSO +.Xr intro 4 , +.Xr ns 4 +.Sh HISTORY +The +.Nm +protocol appeared in +.Bx 4.3 . +.Sh BUGS +There should be some way to reflect record boundaries in +a stream. +For stream mode, there should be an option to get the data stream type of +the record the user process is about to receive. |
