NAME
atalk - AppleTalk protocol family
SYNOPSIS
#include <sys/types.h>
#include <netatalk/at.h>
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.
ADDRESSING
AppleTalk addresses are three byte quantities, stored in network byte
order. The include file <netatalk/at.h> defines the AppleTalk address
format.
Sockets in the AppleTalk protocol family use the following address
structure:
struct sockaddr_at {
short sat_family;
u_char sat_port;
struct at_addr sat_addr;
char sat_zero[ 8 ];
};
The port of a socket may be set with bind(2). The node for bind must
always be ATADDR_ANYNODE: ‘‘this node.´´ The net may be ATADDR_ANYNET
or ATADDR_LATENET. ATADDR_ANYNET coresponds to the machine´s
‘‘primary´´ address (the first configured). ATADDR_LATENET causes the
address in outgoing packets to be determined when a packet is sent,
i.e. determined late. ATADDR_LATENET is equivalent to opening one
socket for each network interface. The port of a socket and either the
primary address or ATADDR_LATENET are returned with getsockname(2).
SEE ALSO
bind(2), getsockname(2), atalkd(8).