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List:       ipng
Subject:    (IPng 2424) Re: advanced sockets api for ipv6 (rcmd's)
From:       rstevens () kohala ! com (W !  Richard Stevens)
Date:       1996-10-31 0:09:44
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[In your message of Oct 30,  4:45pm you write:]
> But with rcmd the application doesn't call gethostbyname.

I'll be more specific, after looking at the source code for rcmd().

Let it still call gethostbyname().  Define a new function

	rresvport_af(int *, int)

[instead of rresvport6()] that takes an address family as the second
argument.  (Given that gethostbyname() and getaddrinfo() both return
an address family to the caller, I'll always opt for a new function
that takes an address family as an argument, instead of something that
only works with IPv6.)  But pass hp->h_addrtype as the second argument
to rresvport_af() and you then have an rcmd() that works with both
IPv4 and IPv6.

There are a few other places in the code that need fixing, for example
some inet_ntoa() that should be inet_ntop(), but the bottom line is that
I don't think we need an rcmd6() function.  I see some other IPv4-specific
pieces of code that need to be changed: for example, the function diddles
with the port number in the socket address structure (sin_port).  I've
written some simple functions, sock_getport() and sock_setport(), that
work with socket address structures and hide all the differences between
sin_port and sin6_port, and I've found these make writing portable
applicatons much easier (portable between IPv4 and IPv6, that is).

	Rich Stevens

p.s. -- Much to my surprise I just did a "man rresvport" to verify that
	the pointer argument is an "int *" and not something else, and
	guess what, you've already defined rcmd6() and rresvport6()!
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