[comp.os.vms] Wanted: quadword addition algoritm

ted@MITRE-BEDFORD.ARPA (09/03/87)

I'm using $GETTIM and $SETIMR to read the system time and set an event
flag.  The result comes back in a quadword as the number of 100ns
intervals since 17-NOV-1858.  (Did they have vaxes back then? :-).
Does anyone have a routine, or know of a language that does/has
operations?  (Sample code would be wonderful, any language will do.
Ada preferred. [stop laughing])  Send code/comments to me.  I'll
summarize and post.

Thanks,
ted
P.S.  I know about $SETIMR(-x) which does delta timing.  I'd rather
not use it because of drift problems.
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tedcrane@batcomputer.tn.cornell.edu (Ted Crane) (09/17/87)

In article <8709031922.AA02189@mitre-bedford.ARPA> ted@MITRE-BEDFORD.ARPA writes:
>I'm using $GETTIM and $SETIMR to read the system time and set an event
>flag.  The result comes back in a quadword as the number of 100ns
>intervals since 17-NOV-1858.  (Did they have vaxes back then? :-).
>Does anyone have a routine, or know of a language that does/has
>operations?  (Sample code would be wonderful, any language will do.

Would the run-time library routines LIB$ADDX, etc., satisfy your need for
operations?  I've found that they do fine for most things, since you only
need to do simple operations on the quadword values and then either use
the results directly or convert them to (and from) ASCII for display
(SYS$BINTIM and SYS$ASCTIM, LIB$SYS_ASCTIM, among others).

Hope that helps, ted.

-ted

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