This file is derived from the atalk.4 man page in the Netatlk 1.4b2
distribution. That distribution is covered by the following copyright:
Copyright (c) 1990,1996 Regents of The University of Michigan.
All Rights Reserved.
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This product includes software developed by the University of
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c/o Wesley Craig
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Ann Arbor, Michigan
+1-313-764-2278
netatalk (at] umich.edu
.Dd November 14, 1997 .Dt ATALK 4 .Os .Sh NAME .Nm atalk .Nd AppleTalk Protocol Family .Sh SYNOPSIS .Fd #include <sys/types.h> .Fd #include <netatalk/at.h> .Sh DESCRIPTION The .Tn AppleTalk Protocol Family provides presentation layer support for the AppleTalk Datagram Delivery Protocol (DDP), using the SOCK_DGRAM socket type. In addition, access to in-kernel AppleTalk routing tables and network interface configurations is provided.
p The AppleTalk Protocol Suite provides support for five kinds of physical media: LocalTalk (230kbps wire-or'd serial), Ethernet, FDDI, Token Ring, and asynchronous serial connections (using either AppleTalk Remote Access
q Tn ARA or .Tn PPP ). Currently, .Nx Ns 's AppleTalk implementataion supports Ethernet, FDDI, and Token Ring.
p AppleTalk packets are encapsulated on the Ethernet using the EtherTalk Link Access Protocol (ELAP). Local network address resolution is handled using the AppleTalk Address Resolution Protocol (AARP). Neither of these protocols is exposed to user-mode applications.
p .Sh ADDRESSING AppleTalk addresses are three byte quantities, stored in network byte order. The include file .Aq Pa netatalk/at.h defines the AppleTalk address format. Sockets in the AppleTalk protocol family use the following address structure: d -literal -offset indent struct sockaddr_at { u_int8_t sat_len; u_int8_t sat_family; u_int8_t sat_port; struct at_addr sat_addr; union { struct netrange r_netrange; char r_zero[8]; } sat_range; }; .Ed
p
The port of a socket may be set with
.Xr bind 2 .
The node for
.Xr bind 2
must always be
.Dv ATADDR_ANYNODE :
``this node.'' The net
may
must
be
.Dv ATADDR_ANYNET .
or
.Dv ATADDR_LATENET .
.Dv ATADDR_ANYNET
corresponds to the machine's ``primary'' address (the first
configured).
.Dv ATADDR_LATENET
causes the address in outgoing packets to be determined when a packet
is sent, i.e. determined late.
.Dv ATADDR_LATENET
is equivalent to opening one socket for each network interface.
The port of a socket and
either
the primary address
or
.Dv ATADDR_LATENET
are returned with
.Xr getsockname 2 .
.Sh PROTOCOLS
The AppleTalk protocol family is comprised of the
.Tn DDP
datagram delivery protocol,
AppleTalk Data Stream Protocol
q Tn ADSP , AppleTalk Echo Protocol
q Tn AEP , AppleTalk Filing Protocol
q Tn AFP , AppleTalk Session Protocol
q Tn ASP , AppleTalk Transaction Protocol
q Tn ATP , Name Binding Protocol
q Tn NBP , Printer Access Protocol
q Tn PAP , and Zone Information Protocol
q Tn ZIP .
p .Tn DDP is implemented in the kernel as .Dv SOCK_DGRAM sockets in the .Dv AF_APPLETALK address family. .Nx implements all other .Tn AppleTalk protocols using the .Tn Netatalk package. .Tn Netatalk implements all functions except for .Tn ADSP and an .Tn AFP client. .Tn AEP , .Tn NBP , and .Tn ZIP services are provided by the .Tn atalkd daemon. .Tn ASP and .Tn ATP services are provided by a user library. .Tn PAP and .Tn AFP services are provided by user programs and daemons.
p
.Sh SEE ALSO
.BR ddp (4P),
.BR atp (3N),
.BR asp (3N),
.Xr bind 2 ,
.Xr getsockname 2 ,
.Xr options 4 ,
.Xr atalkd 8 .
.Rs
.%B Inside AppleTalk, second edition
.%A Gursharan S. Sidhu
.%A Richard F. Andrews
.%A Alan B. Oppenheimer
.Re
Indexes created Mon Oct 20 20:10:13 GMT 2025