Subject: Re: DATE-OBS='31/12/99'

From: seaman at noao.edu (Rob Seaman)
Date: 10 Jul 1996 17:53:09 GMT

Barry M. Schlesinger writes:

> The eight character rule stemmed from some limitations of hardware 
> and/or software.  Every once in a while I still see notes about some 
> package that has a problem with longer strings.

Eight ASCII characters also form a 64 bit "magic" number.  This can
be used to discriminate extension types, for example, by using similar
techniques to the unix "file" command (note that /etc/magic also allows
for an byte offset).  The value isn't double word aligned, unfortunately,
since it has to start in column 12.

Rob
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