topic Re: Is there integer limit in HP-UX ksh? in Operating System - HP-UX

Is there integer limit in HP-UX ksh?

Louis Liu_1 — Tue, 15 Aug 2006 03:22:53 GMT

I added 2 big integer numbers and got a negative number. for example:

$ (( i = 4190246798 + 4190246798 ))
$ echo $i
-209440996

Please ksh expert explain the reason.
BTW, I try the same example in Solaris, Solaris ksh can give correct result. Please try.

Re: Is there integer limit in HP-UX ksh?

Ralph Grothe — Tue, 15 Aug 2006 03:28:18 GMT

You should use bc for those bigint arithmetics.
I'm not sure if a typeset -i declaration can cope, but man ksh should tell.

Re: Is there integer limit in HP-UX ksh?

john korterman — Tue, 15 Aug 2006 03:38:28 GMT

Hi,

the posix shell only supports 32 bits integers, i.e. max 2147483648

Try Ralph's suggestion, e.g.:
# echo "4190246798 + 4190246798" | bc
8380493596

regards,
John K.

Re: Is there integer limit in HP-UX ksh?

Peter Godron — Tue, 15 Aug 2006 03:38:54 GMT

Louis,
looks like 2^31 is the limit.

Re: Is there integer limit in HP-UX ksh?

A. Clay Stephenson — Tue, 15 Aug 2006 08:57:34 GMT

It's a 32-bit signed integer and thus the range is -(2^31) to +(2^31 - 1).

Re: Is there integer limit in HP-UX ksh?

Peter Godron — Thu, 17 Aug 2006 03:41:12 GMT

Louis,
if you are happy with the solutions given, can you please reward good answers, see

http://forums1.itrc.hp.com/service/forums/helptips.do?#28

and close the thread.