linkaddr3
Elementary address specification routines for link level access
Usage
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if_dl.h>
void
link_addr(const char *addr, struct sockaddr_dl *sdl);
char *
link_ntoa(const struct sockaddr_dl *sdl);
Library
Standard C Library (libc, -lc)
Overview
The routine link_addr() interprets character strings representing link-level addresses, returning binary information suitable for use in system calls. The routine link_ntoa() takes a link-level address and returns an ASCII string representing some of the information present, including the link level address itself, and the interface name or number, if present. This facility is experimental and is still subject to change.
For link_addr(), the string addr may contain an optional network interface identifier of the form “name unit-number”, suitable for the first argument to ifconfig(8), followed in all cases by a colon and an interface address in the form of groups of hexadecimal digits separated by periods. Each group represents a byte of address; address bytes are filled left to right from low order bytes through high order bytes.
Thus le0:8.0.9.13.d.30 represents an ethernet address to be transmitted on the first Lance ethernet interface.
Return values
The link_ntoa() function always returns a null terminated string. The link_addr() function has no return value. (See BUGS.)
Releases
155 releases since Mac OS X 10.2; the text changed 3 times.