topic Re: Korn shell question in Operating System - HP-UX

Korn shell question

Quark — Tue, 05 Feb 2008 13:13:58 GMT

Hi,

I wanted to write a ksh script that uses arrays.
Since I was not familiar with the syntax, I looked up some code on the net.
This is what I found:
"
typeset -A wavelength

wavelength["red"]=650
wavelength["orange"]=590
wavelength["green"]=510
wavelength["blue"]=475
wavelength["indigo"]=445
wavelength["violet"]=400
"

This is what I want to do but when test this code then 'typeset -A' is not recognised.
If replace 'typeset -A' by 'set -A' then I get 'red: bad number'

It seems that version of Korn shell on my system is to old (not Korn 93). I am running 11.11.

Is this correct or is the syntax just wrong?

Any help much appreciated.

KRis

Re: Korn shell question

James R. Ferguson — Tue, 05 Feb 2008 13:22:08 GMT

Hi Kris:

The standard HP-UX version of the Korn shell found in '/usr/bin/ksh' is Korn88. You can find the Korn93 version as:

/usr/dt/bin/dtksh

Regards!

...JRF...

Re: Korn shell question

Hein van den Heuvel — Tue, 05 Feb 2008 13:25:52 GMT

KRis,

It may well be that an Ksh script with arrays is the optimal (learning, processing, price, security, tools) way to solve the challenge on hand.

However, in my experience most such task are better done in AWK or PERL.

What problem are you really trying to solve?
Outline it here (with concrete input and output) and we may be able to help you better.

Regards,
Hein.

Re: Korn shell question

Oviwan — Tue, 05 Feb 2008 13:27:42 GMT

Hey

with set -A you can only use integer as index of the array. check man ksh

Regards

Re: Korn shell question

Steven Schweda — Tue, 05 Feb 2008 15:20:53 GMT

And what happened to "yellow"?

Re: Korn shell question

Ralph Grothe — Tue, 05 Feb 2008 15:26:02 GMT

From your sample snippet,
what you want is a hash
(or a so called associative array).
I am not into Korn shell in particular
because I never require it.
As for most array capable shells,
they expect indeces to be unsigned integers
(often only ranging from 0-1023).
But you can script in awk, Perl, Python or Ruby for key value paired lists.

Re: Korn shell question

Zeev Schultz — Tue, 05 Feb 2008 15:59:41 GMT

no "typeset -A" in hpux ksh. use "set -A name variable" instead.

Moreover,I'm convinced that ksh array is a standard 1-level array with index. I.e you should use : wavelength[1]="red",[2]="orange" and so on. What you may need here is a named reference. It is nicely implemented with perl's hashes. ksh93 gives associative arrays,as well,there you can use strings as an index.

Re: Korn shell question

James R. Ferguson — Tue, 05 Feb 2008 16:16:02 GMT

Hi (again):

While I agree that associative arrays are better handled in 'awk' or Perl (where they are called "hashes"), you _CAN_ do this with the Korn93 shell _ON_ HP-UX with as I noted above. You must use :

/usr/bin/dt/dtksh

Regards!

...JRF...