Re: Environment Variable weirdness

[Brian Servis <servis@purdue.edu>]

The first two variables are set by the shell and are determined either
at compile time or by the environment it starts up in.  Read the man
page for your shell.  For bash it says the following:

       HOSTTYPE
              Automatically   set   to  a  string  that  uniquely
              describes the type of machine on which bash is exe­
              cuting.  The default is system-dependent.
[...]
       MACHTYPE
              Automatically  set to a string that fully describes
              the system type on which bash is executing, in  the
              standard   GNU   cpu-company-system   format.   The
              default is system-dependent.

Others have described how they are used and what they pertain to.


*- On 29 Sep, Salman Ahmed wrote about "Environment Variable weirdness"
> 
> (1)
> Running Debian 2.1, I noticed sth odd about a couple of 
> environment variables (I am running XFree-3.3.3.1-2).
> 
> First of all :
> 
>     HOSTTYPE=i386-linux
> 
> I have a Celeron 300A processor and have installed a new
> 2.2.12 kernel recently. Where is this variable getting
> set from ?
> 
> How do I change this env variable on a global basis ?
> 
> Same thing for the MACHTYPE env variable :
> 
>     MACHTYPE=i386
> 
> Why do these variables refer to i386 when the arch
> command displays the correct output :
> 
>     @phoenix:[/home/ssahmed] arch
>     i686
> 
> 
> (2)
> The other thing is that the DISPLAY env variable is set
> to "unix:0.0". My question is : shouldn't this variable
> be of the form $HOSTNAME:0.0 ? So why is set to "unix:0.0" ?
> 
> And how do I change this env variable on a global basis
> (ie for all users) ?
> 
> 
> (3)
> The last thing is : I'd like to create an environment variable
> that contains the following information : kernel version and
> machine architechture. e.g. : linux-2.2.12-i686. Let's call
> it OSVERSION. Where do I set this environment variable ?
> 
> Thanks.
> 
> 

-- 
Brian 
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Mechanical Engineering                              servis@purdue.edu
Purdue University                   http://www.ecn.purdue.edu/~servis
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