>quantity in two four bit hardware registers) to "00". Since RT-11 (I
>know - I can't get away from it) has 1973 as the earliest legal date, I
Actually, the lowest date for RT is 1972... that is the beginning of
the 'RT Epoch'... :-)
>wrote the software to assume that any year value less than "70" was after
>1999. In addition, back in 1993 or maybe as late as 1994, I patched the
>code for the actual RT-11 OS (V5.6 of RT-11) to do the same thing. This
>was not the standard that was finally adopted for V5.7 of RT-11 wherein
>any date after 1999 was required to specify a four digit year, but it is
>very obvious that many other people were already using the concept of a
>pivot date long before 1998. I also modified some software for a company
>that makes cars (you know those big hunks of metal with four wheels and a
>nut in the front seat) - I think that was delivered in 1997 and those
>patches also used a pivot date concept. So I doubt that it will take
>much to prove that the granting the patent was "inappropriate".
>Anyone else have any stories about using a pivot date some time ago!
Yep...
Back when I was doing some 'private advanced development' of RT-11
post-V5.6, and before Mentec started work on V5.7, I implemented just that
sort of thing (I think it was about 1995 or so, but I'll have to check my
files). I had, for example, the DATE command modified so that it would
accept both 2-digit and 4-digit year specifications. If the year
specified was 72 to 99, it was assumed to be 1972 to 1999. If it was 00
to 71, it was assumed to be 2000 to 2071. Years 2072 to 2099 (the limit
handled by the RT-11 date format) would *have* to be specified in the
4-digit form.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '_at_' in place of '!' |
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+--------------------------------+-------------------------------------+
Received on Fri Nov 12 1999 - 20:22:36 GMT