A Micro release binding is asserted.  The interface exported is
Stable.

Most UNIX systems, save Solaris, have had a TCP/IP utility function
called 'inet_aton' for ages.  This function is similar in purpose to
the even older 'inet_addr' function, but repairs an obvious defect in
the interface that latter function offers: there's no way to
distinguish between the all-ones IPv4 broadcast address and just
abject parsing failure.

We've avoided adding this function as it didn't fit with our future
direction for inet_pton and (later) getaddrinfo.  Nevertheless,
developers used it and continue to use it for new applications, and
were then faced with unnecessary difficulties in porting to Solaris.
As a result, many such applications either supply their own (often
hackish) version of the function, or just don't compile on Solaris.

This case establishes inet_aton as a Stable interface.  As with its
siblings, this will be exported by libnsl and documented along with
the existing functions in inet(3SOCKET).

For reference (as this is commonly defined by its behavior on 4.4BSD),
the interface is:

	extern int inet_aton(const char *cp, struct in_addr *addr);

Where:

	'cp' points to an IPv4 address in one of the classic
	dotted-decimal forms (a.b.c.d, a.b.c, a.b, or a).

	'addr' points to the result to be returned.

	The return value is 1 if conversion is successful, 0
	otherwise.

Internally, we currently define this symbol as a "private" interface
in libresolv, because that library needs the function to operate
correctly.  In addition, some users "accidentally" discovered that
linking with libresolv made the function available, and likely believe
(despite the lack of documentation) that this is the right thing to do
on Solaris.

The actual implementation will do three things:

	- Move the existing inet_aton function out of libresolv and
          into libnsl, making it public in libnsl.

	- Make inet_aton a weak symbol with the strong _inet_aton used
          for internal ON libraries (to avoid accidental linkage with
          user-supplied hackish variants).

	- Verify that existing users who may have "discovered"
          the symbol in the wrong location will still see through to
          the new (and supported) libnsl version without having to
	  relink.