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A bit pf trivia ...

Long ago and far away, I worked at Link Flight Simulation of the Singer Company; we ran MVS/SP on an IBM 4341. There, on the week of 8 June 1984, an operator blew the Julian date when doing an IPL by flipping two digits. This jumped the date forward ~ 3 months and THAT caused the tape library scratch processing to have a field day and threaten to wipe out good chunk of our tape library.? (The librarians caught it promptly, thank goodness.)

I know the week because on that date I cranked out a simple program that was started immediately after IPL and displayed on the console a non-scrollable line similar to:

@LDCTODAY: Monday, 25 July 2022 (22.206)

This of course made it easy for the operator to promptly see the error of their ways.

Because I'm prone to not check the time when I IPL MVS 3.8 (after all it is slaved is to the NTP-controlled Hercules host clock except for the timezone), I recently played with the program and its underlying date routine to expand the output to report the time and timezone, and as a bonus I tossed in a second message with the GMT date and time:

@LDCTODAY: Monday, 25 July 2022 (22.206)? 9:36:19 AM -0700
@ Monday, 25 July 2022 (22.206)? 4:36:18 PM GMT

The times sources are generated by the OS TIME macro invoked twice back-to-back:

???????? TIME? DEC,ZONE=LT???????? Get current local time ...??????? ?
???? ST??? R0,LCLTIME??????????????????????????????????????????? ?
???? ST??? R1,LCLDATE??????????????????????????????????????????? ?
???? SPACE 1???????????????????????????????????????????????????? ?
???? TIME? DEC,ZONE=GMT??????? ... also get current GMT time ... ?
???? ST??? R0,GMTTIME??????????????????????????????????????????? ?
???? ST??? R1,GMTDATE????

Now knowing you did not look closely at the program output, back up and look at it carefully.

Like how time flows backwards?? My uninformed guess is a truncate issue deep in MVS with the conversion from timer units to seconds*100 and then the hundredths are dropped.

(My time working in RBOC class voice mail has taught me well: NO lossy conversion goes unpunished.)

-ahd-

-- 
Drew Derbyshire

AAAAAA - American Association Against Acronym Abuse Anonymous.