AF_CCITT(7F)

Requires Optional X.25 Software

NAME

AF_CCITT − CCITT address family

SYNOPSIS

#include <sys/types.h>
#include <x25/ccittproto.h>

DESCRIPTION

AF_CCITT identifies protocols within the address-family CCITT, such as X.25.

Addressing

The include file <x25/x25addrstr.h> contains the declaration of the x25addrstr struct. Pointers to x25addrstr are used in various system calls.

There are six fields of interest within this structure. The first field is x25_family, which must be set to AF_CCITT. The second field is hostlen which contains the length of the X.121 address in digits. The third field is pidlen which contains the length of the x25pid field in bytes. The fourth field is which specifies a protocol-ID. A protocol-ID is a loosely-defined convention designating a number of bits in the Call-user data field of an INCOMING CALL packet as the protocol- ID. The protocol- ID is specified in 1 to 8 bytes. The fifth field is x25_host[], which is the X.121 address of the destination for a connection request, or the address to which the socket is bound. The X.121 address is a string of 1 to 15 digits, including subaddesses if subaddesses are supported on the network provider. The sixth field is x25ifname[], the name of the local X.25 interface through which a connection will be established, or to which the socket is to be bound. The X.25 interface name is a string of 1 to 12 alphanumeric characters, terminated by the null character.

Socket Buffer Size

The maximum buffer size for a stream socket in the AF_CCITT family is 65535 bytes. The default buffer size is 4096 bytes. The send and receive buffer sizes for AF_CCITT stream sockets can be altered by using the SO_SNDBUF and SO_RCVBUF options of the setsockopt() system call. See getsockopt(2) for details.

AUTHOR

af_ccitt was developed by the University of California, Berkeley.

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