.TH atalk 4 "17 Dec 1991" 2.0.0 Netatalk 
.SH NAME
atalk \- AppleTalk protocol family
.SH SYNOPSIS
.nf
#include <sys/types.h>
#include <netatalk/at.h>
.fi
.sp 1
.SH DESCRIPTION
The AppleTalk protocol family is a collection of protocols layered
above the Datagram Delivery Protocol (DDP), and using AppleTalk address
format. The AppleTalk family may provide SOCK_STREAM (ADSP), SOCK_DGRAM
(DDP), SOCK_RDM (ATP), and SOCK_SEQPACKET (ASP). Currently, only DDP is
implemented in the kernel; ATP and ASP are implemented in user level
libraries; and ADSP is planned.
.SH ADDRESSING
AppleTalk addresses are three byte quantities, stored in network
byte order. The include file <\fInetatalk/at.h\fR>
defines the AppleTalk address format.
.PP
Sockets in the AppleTalk protocol family use the following address
structure:
.PP
.nf
struct sockaddr_at {
    short sat_family;
    u_char sat_port;
    struct at_addr sat_addr;
    char sat_zero[ 8 ];
};
.fi
.PP
The port of a socket may be set with \fBbind\fR(2).
The node for \fIbind\fR must always be \fIATADDR_ANYNODE\fR: ``this node.'' The net may be
\fIATADDR_ANYNET\fR or \fIATADDR_LATENET\fR.
\fIATADDR_ANYNET\fR coresponds to the
machine's ``primary'' address (the first configured).
\fIATADDR_LATENET\fR causes the address in
outgoing packets to be determined when a packet is sent, i.e. determined
late. \fIATADDR_LATENET\fR is equivalent to
opening one socket for each network interface. The port of a socket and
either the primary address or \fIATADDR_LATENET\fR
are returned with \fBgetsockname\fR(2).
.SH "SEE ALSO"
\fBbind\fR(2),
\fBgetsockname\fR(2),
\fBatalkd\fR(8).