Default list of exported variables in sh(1) - $HOSTNAME

[Mel]

On Wednesday 24 December 2008 10:22:34 Brian A. Seklecki wrote:
> All:
>
> I've got a fun problem ...
>
> I'm having trouble tracking down where the default list of exported
> variables is set for sh(1).
>
> I've got a piece of PHP code that runs on GNU/Linux but not FreeBSD
> because (I think) $HOSTNAME is exported by default.
>
> The PHP CLI calls $_ENV["HOSTNAME"], which under GNU/Linux returns:
>
> $ php -r 'print gethostbyaddr(gethostbyname($_ENV["HOSTNAME"]))'
> soundwave.ws....collaborativefusion.com
>
> In HTTP/CGI mode, I can call $_SERVER[]. But $_ENV[] should work in both
> CLI and HTTP mode.
>
> However, because Apache is spawned from sh(1) from rc(8) and in FreeBSD
> 6.x, $HOSTNAME is not exported by default, which is what $_ENV[] uses
> (getenv()):
>
> $ uname -a
> FreeBSD bdb00 6.3-RELEASE-p2
> $ export
> SSH_CLIENT
> USER
> MAIL
> HOME
> SSH_TTY
> PAGER
> ENV
> LOGNAME
> BLOCKSIZE
> TERM
> PATH
> SHELL
> SSH_CONNECTION
> FTP_PASSIVE_MODE
> EDITOR

I suspect linux to set them from .profile files (even /etc/profile) and not 
hardcoded in a shell or login program. The default skeletons 
in /usr/share/skel on FreeBSD does not set them. Neither 
does /etc/login.conf.
I would set it in /etc/profile.

-- 
Mel

Problem with today's modular software: they start with the modules
    and never get to the software part.