Date   : Thu, 03 Dec 1987 02:37:50 GMT
From   : poisson.usc.edu!mlinar@oberon.usc.edu (Mitch Mlinar)
Subject: Re: Z80DOS, PZDOS and datestamp formats

In article <1505@copper.TEK.COM> michaelk@copper.UUCP (Michael D. Kersenbrock
writes:
>
>Actually, I'd think that the cp/m 3.0 "type" stamps that are
>actually cp/m 3.0 compatible would be the most portable.  It would
>allow 2.2 users to be compatible with the already existing standard
>as defined by DRI in CP/M 3.0.
>
>>It would be desirable to standardize on a single format for all of
>>cp/m 2.2; that would enable all of us to use all of the
>>timestamp-featured utilities that already exist (directory, filecopy,
>>disk catalog, unix-make, for DateStamper) and are being developed, and
>>
>>--bridger mitchell
>
>With a timestamp compatible with CP/M 3.0, ALL CP/M-80's would use a
>single format!  existing CP/M 3.0 utilities (such as UNIX-like "make")
>may be usable by 2.2 users (see the CPM3 section of Simtel20 archives).

I disagree with both postings to some extent.

(1) QP/M is actually just as portable as DateStamper and is a drop-in
replacement for CP/M 2.2.  Read this: you give up *no* extra memory and
*no* directory entries to have full time/date stamping of create/update/
backup.  If you don't have a real-time clock, that is ok; but having some
sort of counting clock helps.  You need a Z80 for this guy.  QP/M was
written from scratch as a Z80 operating system compatible with CP/M;
DateStamper was initially a set of patches to 2.2 but has evolved some
since.  I think both are fine (but I am biased to QP/M since I wrote it :-).
We already have a full set of utilities (such as QSWEEP, QPIP, QSTAT, QDIR,
QBACKUP, MAKEQ, CATALOGQ) available which uses the time/date value -
primarily through DOS calls explicitly assigned to time/date stamping.

(2) I take issue with the CP/M 3.0 method of stamping disks.  Only
a *single* date/time is supported (yuck), but you GIVE UP DIRECTORY ENTRIES.
Maybe this is not a problem when you:
     (a) start with a virgin disk
     (b) don't mind moving files to reformat
     (c) all of your files are large
but it has been my experience that the ratio of disk use to directory
use on many systems is pretty close percentage wise.  Floppy formats are
fixed, and it is stupid to increase the number of directory entries just
for CP/M 3.0.  A similar thought for hard drives: why search through all those
extra FCB entries which are really filename related?  A time/date file
(such as used by DateStamper [or was] and by QP/M) is a better alternative
in the CP/M world.


On the issue of compatibility, I agree completely.  Let's standardize
on something, the first being a time/date DOS call that fetches all of
the time/date information for a given file.  That way, even on the different
OSes, at least all time/date DOS calls would work.  A complete standard would
be much more difficult to implement at the file/directory level - as the
issues here can become religious :-)

-Mitch