Re: Mac OS X 10.1 File Name Extension Guidelines
Re: Mac OS X 10.1 File Name Extension Guidelines
- Subject: Re: Mac OS X 10.1 File Name Extension Guidelines
- From: Bill Chin <email@hidden>
- Date: Mon, 10 Sep 2001 00:30:23 -0400
On Sunday, September 9, 2001, at 01:49 PM, Brendan Younger wrote:
On Sunday, September 9, 2001, at 12:17 PM, Bill Chin wrote:
On Sunday, September 9, 2001, at 10:13 AM, Mark Munz wrote:
Wait, isn't putting the definition of what type of document I'm
dealing with
a throwback to the early years when disk space was expensive and in
short
supply, when saving 4 bytes was crucial, when we used .txt to define
a text
file and such. Apparently we haven't come very far.
Actually, with file name extensions, I can create an application that
uses .hypertext as an extension under Mac OS X today. With current
HFS+ implementation, we're limited to 4 character type codes (HTXT).
Which one is more limiting?
The fact that it is a four "character" code does not in *any* way limit
it. It's implemented as a long int and can thus have up to 4294967295
possible values. That is far more than will ever be needed.
Hmmm. Mark Munz was talking about saving disk space, "when saving 4
bytes was crucial" and that somehow file extensions was related to that.
My point is that file extensions, as implemented today, have a larger
potential namespace than the 4 character type codes, so disk space isn't
the issue. Of course, a 32 bit unsigned int does have a limit - you
stated it.
Also, the fact that it is completely hidden from the user and only
its manifestation is presented is a point for it over file extensions.
(No one actually cares whether it's hTXT or HTXT or HTEX, a program
that wants to know it's type just looks for the appropriate code. No
aesthetic judgement is necessary.)
Ah, yeah. Of course, when you actually have to change it, you have to
remember the right number out of 4294967295 possible values, or worse,
picking the right one out of a list that scrolls forever. This
effectively makes the number of really useful values much lower. Unless
you want to be the developer that ships an application where users have
to change the type of a document to "@!(>" for the system to recognize
it properly.
..Bill Chin
M Dimension Technology