[HECnet] Another date limit?

[Johnny Billquist]

On 2019-08-01 22:44, Paul Koning wrote:
> In the Phase IV network management spec the description of the encoding of the event log message has this field:
> 
>                             JULIAN HALF DAY (2) :  B  Number  of  half  days
>                                                       since  1  Jan 1977 and
>                                                       before  9   Nov   2021
>                                                       (0-32767).         For
>                                                       example,  the  morning
>                                                       of Jan 1, 1977 is 0.
> 
> It's a 16 bit field containing a 15 bit value; there is no explanation why the upper bit is not used even though it's marked as an unsigned integer.
> 
> As shown, the field overflows in late 2021.  If one ignores the arbitrary limit of 15 bits, the end date is 18 September 2066, which is more civilized.
> 
> I wonder if implementations ignore the 15 bit limit.  I think RSTS/E ignores it.

Yes, RSX treats it as unsigned 16 bits. It's even documented in the 
release noted for RSX-11M-PLUS V4.6. Section 8.8.2, page 8.7.

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
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