Re: heimdal on GNU HURD

[Thomas Bushnell, BSG]

"Jacques A. Vidrine" <n@nectar.com> writes:

> OTOH I don't think that an arbitrarily long hostname makes much
> sense.

Really?  Have you seen proposals for handling internet growth?
Hostnames are already getting longer and longer.  I was once at
"unmvax".  Then that became "unmvax.unm.edu".  Now my laptop has the
attractive address "vp190095.reshsg.uci.edu".  Indeed, BSD added a
field to utmp for the remote host name, and that field (go figure) was
something like 12 characters, and so major hassle ensued to make it
bigger.

> I don't accept that this is the only correct thing to do.

Another way is to have an interface to fetch the length of the
hostname first, and then allocate a suitably sized buffer, or else use
an interface that allocates its own buffer.  

> I was  quite happy to  have the problem (with  MAXHOSTNAMELEN) pointed
> out.  I  am not  happy to  add new complexity  to applications  for no
> gain.

What about the gain of Posix compliance?  Two messages ago, you were
insisting that Posix said you were right.  And then, when Posix
actually says you're wrong, now what?  Posix is no longer worth
attention? 

> It is laudable  that you want to do away  with `arbitrary limits', and
> it is  laudable that you  (apparently) want to be  POSIX-compliant.  I
> think  it  is  shameful,  however,  that  the  Hurd  will  not  define
> MAXHOSTNAMELEN  or even  HOST_NAME_MAX: this  seems to  be biting  the
> thumb at portability.

We HAVE no limit.  Why should we invent one?  What need is there to
deliberately break our system?

> For  gethostname,  one can  use  it  in  a  manner that  is  portable,
> POSIX-compliant, and  simple by using the  appropriate constant (which
> is defined by the OS).  Unlike the case with pathnames, there does not
> seem to be any benefit in  adding complexity to support lengths longer
> than the minimum specified by POSIX.

It's not Posix compliant if you code only works when HOST_NAME_MAX is
defined, because Posix *explicitly* allows it not to be defined when
it would not make sense to on a particular system.

> I  don't  really  have  a `problem'  with  implementing  functionality
> similar to  xgethostname -- I  just think that  it is rather  silly to
> jump through such hoops for a basic operation.

Then can we please do that?  It is just more flexible all round.

> Lastly, this  in no  way means  that it acceptable  for Heimdal  to be
> broken on the Hurd.  It will be fixed one way or another.

Good!  I'm glad we agree about the most important things. :)