Re: Hostname/Domainname Bug?

Seemant Kulleen wrote:
> Me again. I added 4.5.11 to gentoo's portage today.  Our developer,
> Azarah noticed:
> 
>       I do not know if this is a bug or feature, but 'hostname'
>       symlinked/copied to domainname still sets the hostname.

Hmm...

1. The GNU standards don't allow programs to change their behavior by
   being linked or renamed.

     http://www.gnu.org/prep/standards_16.html#SEC16

      "Please don't make the behavior of a utility depend on the name
      used to invoke it. It is useful sometimes to make a link to a
      utility with a different name, and that should not change what
      it does."

   The rationale being that people often need to install GNU project
   software by other names to avoid name collisions with the native
   programs.  The case that gnu compiler is installed gcc instead of
   cc for the classic example.

   Therefore in general with gnu software (of course there are
   exceptions) renaming or linking programs won't change their
   behavior into a different program.

2. The 'domainname' program is not part of GNU coreutils.  There are
   several options here.  You may be talking about these programs from
   the yp-tools package.

     http://www.linux-nis.org/
     ftp://ftp.kernel.org/pub/linux/utils/net/NIS

   Or possibly you are talking about these programs from the the
   net-tools package.

     http://www.tazenda.demon.co.uk/phil/net-tools/

   The 'domainname' command is an NIS/YP command.  It has nothing to
   do with hostnames.  On NIS/YP systems it returns the YP domain of
   the system.  The poor choice of command names has led to much
   confusion with DNS domain names over the years.  But so it is.

   Note that there is no "standard" to cover the 'domainname' command.
   It usually does not exist on systems unless NIS/YP is installed.
   Usually today there are other extensions installed beside it such
   as dnsdomainname to try to compensate for the confusion caused by
   the poorly named 'domainname' command.  I personally would not
   write a script that used any of them.  However, it would be
   perfectly fine to use them in a system startup since presumably
   system startup scripts know the capabilities of the system they are
   trying to start.

   <rant> As a particular point that I have been burned by on a number
   of occasions is that the '-f' option to hostname is an extension.
   Scripts that use that option tend to change the hostname to '-f' on
   non-gnu systems.  Please avoid doing that.  In any case, the
   function of that option is dependent upon the environment in which
   the program is run and can't be counted upon. </rant>

Bob