I did look for IBM docs online, but I haven't found anything very helpful.

I read of someone using STCK and converting (the hard way!) to display
time, instead of using TIME DEC. So I tried it on my Hercules/MVS 3.8 setup.

I was expecting to have to account for all the leap seconds since 1972. I
mean that a hypothetical system running for decades would presumably have
been running its TOD clock during leap seconds.

I'll improve the code to print out the exact difference, but should I
expect any difference, or have I made a mistake?

As a quick check, I used TIME STCK, did the equivalent of a shift right by
12 bits and dividing by (1,000,000*3600*24) for days, subtracted 28 leap
days and then divided by 365 for years. UNPK the remainder for days.

I left this running overnight, looping roughly twice a second. I expected
my date from STCK to change sooner than TIME DEC by a few seconds due to
leap seconds since 1972, but it matched all night, including midnight.

Perhaps the TOD clock is slowed or stalled for leap seconds, to keep
TOD-derived date and time in synch with solar time?

It's amazing how much detail there is.

Roops.

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN

Reply via email to