[Gllug] $HOSTNAME

[Hari Sekhon]

John G Walker wrote:
> On Tue, 8 Sep 2009 16:32:50 +0100 Stephen Nelson-Smith
> <sanelson at gmail.com> wrote:
>
>   
>> It's probably safer to use $(hostname -s)
>>     
>
> Safer in what way? I just use the name as a string
Technically $HOSTNAME can be blank (but usually isn't) but hostname -s 
seems more likely to return something as it uses the system's 
gethostname function call which pulls the hostname from sysfs and one 
would think it's safer but I just tested it and it's not really any 
safer, you could blank that out too for example or change it to the name 
of another machine on the network and hostname -s will happily return 
that or an unknown host error if it's blank or not resolvable.

Some elementary shell scripting will allow you to test for any of this 
though... and if you're writing anything without such tests then your 
code simply isn't robust, and shell scripting usually garners criticism 
from people who aren't very adept at writing it for this very reason. 
Defensive programming should be employed regardless.

-h

-- 
Hari Sekhon
http://www.linkedin.com/in/harisekhon

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