Unix: Why is Hosts file NOT case-sensitive?

Hi all!

I have a question that's bugging me!

Does anyone know why the /etc/hosts file on a Unix system is NOT case-sensitive?

As we all know, Unix systems are case-sensitive, so I wonder how this slipped through the net!

The reason I ask, is because it's actually causing me some hassle as the hosts file on one of my Network Management Systems is used in an import script for use by another system - The applications ARE case-sensitive this mis-match, means I have a bug to fix!

Any explanation of this would be interesting, because it just seems wierd to me!

Many thanks for any insight on this


Who is Participating?
Jeff DarlingConnect With a Mentor Developer AnalystCommented:
If you are refering to host names in the hosts file, they are not sensitive to case.

RFC1035 sec 2.3.1 <http://www.ietf.org/rfc/rfc1035.txt>

"Note that while upper and lower case letters are allowed in domain
names, no significance is attached to the case. That is, two names with
the same spelling but different case are to be treated as if identical."
Is this homework question?
Some old systems require tld to be capital, but who cares nowadays.
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Why you are linking hostnames to UNIX? This has to do with networking! Networking protocols are not developed by UNIX developers. They are used on many systems.

marcusjonesAuthor Commented:
To ghiest:

No this is not a homework question! I explained in the original post, this behaviour actually means that 'sloppy' entries in the hosts file on one system, then cause problems with an application on another system, because the hosts file is used as an input file for another script

Hosts files may not be case-sensitive, but many COTS software products are, so when you're integrating many disparate systems this can present problems

To jeffid:

Thanks for your reply. That's exactly what I needed to know. As it's in this RFC, I can now see why they decided to make the hosts file case-insensitive also

At least if anyone asks what the problem is, I'll be able to explain it a little more fully now :)
marcusjonesAuthor Commented:
To omarfarid:

I linked it to Unix, because it was a 'Unix Networking' question. My question was directly related to case-sensitivity of the hosts file on a Unix System

If seemed like reasonable logic to me...
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