From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <899a6a33f1807a18fb47a7463792ebe6@plan9.jp>
To: 9fans@cse.psu.edu
From: Joel “chesky” Salomon <chesky@plan9.jp>
Date: Tue, 17 Oct 2006 23:10:57 -0400
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Subject: [9fans] csipinfo
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My homework assignment reads:
> Write a program to receive multiple UDP messages ...  Print to
> standard output the remote host and port from which the message
> originated (print the dotted decimal IP address and also use
> gethostbyaddr to print a textual host name), followed by the message
> itself.

I=E2=80=99ve got everything but the gethostbyaddr equivalent code.  From
cpu% sig csipinfo
	Ndbtuple* csipinfo(char *netroot, char *attr, char *val, char **attrs, i=
nt nattr)
it looks as if I should do something like:
	lfd =3D listen(adir, ldir);
	if (lfd < 0) sysfatal("listen: %r");
	dfd =3D accept(lfd, ldir);
	if (dfd < 0) sysfatal("can't accept: %r");
	NetConnInfo	*i =3D getnetconninfo(nil, lfd);
	Ndbtuple		*t =3D csipinfo(nil, "????", "????", ["ip", "dns"], 2);
	...
=E2=80=94 but what=E2=80=99re the attr and val arguments to csipinfo?  I=E2=
=80=99ve read
ndb(2) and been thoroughly confused, and
http://www.google.com/codesearch turns up no uses of csipinfo, only
its implementation on Plan 9 and plan9ports.

Specifically, what attribute=3Dvalue pair do I know about for this
remotely-initiated connection?

Thanks,
--Joel