NS(3) BSD Library Functions Manual NS(3)NAME
ns_addr, ns_ntoa — Xerox NS(tm) address conversion routines
SYNOPSIS
#include <sys/types.h>
#include <netns/ns.h>
struct ns_addr
ns_addr(char *cp);
char *
ns_ntoa(struct ns_addr ns);
DESCRIPTION
The routine ns_addr() interprets character strings representing XNS
addresses, returning binary information suitable for use in system calls.
The routine ns_ntoa() takes XNS addresses and returns ASCII strings rep‐
resenting the address in a notation in common use in the Xerox Develop‐
ment Environment:
<network number>.<host number>.<port number>
Trailing zero fields are suppressed, and each number is printed in hexa‐
decimal, in a format suitable for input to ns_addr(). Any fields lacking
super-decimal digits will have a trailing ‘H’ appended.
Unfortunately, no universal standard exists for representing XNS
addresses. An effort has been made to insure that ns_addr() be compati‐
ble with most formats in common use. It will first separate an address
into 1 to 3 fields using a single delimiter chosen from period ‘.’, colon
‘:’ or pound-sign ‘#’. Each field is then examined for byte separators
(colon or period). If there are byte separators, each subfield separated
is taken to be a small hexadecimal number, and the entirety is taken as a
network-byte-ordered quantity to be zero extended in the high-network-
order bytes. Next, the field is inspected for hyphens, in which case the
field is assumed to be a number in decimal notation with hyphens separat‐
ing the millenia. Next, the field is assumed to be a number: It is
interpreted as hexadecimal if there is a leading ‘0x’ (as in C), a trail‐
ing ‘H’ (as in Mesa), or there are any super-decimal digits present. It
is interpreted as octal is there is a leading ‘0’ and there are no super-
octal digits. Otherwise, it is converted as a decimal number.
RETURN VALUES
None. (See BUGS.)
SEE ALSOhosts(5), networks(5),
HISTORY
The ns_addr() and ns_toa() functions appeared in 4.3BSD.
BUGS
The string returned by ns_ntoa() resides in a static memory area. The
function ns_addr() should diagnose improperly formed input, and there
should be an unambiguous way to recognize this.
4.3 Berkeley Distribution June 4, 1993 4.3 Berkeley Distribution