topic Re: Use content of variables to get content of variable in Operating System - Linux

Use content of variables to get content of variable

OFC_EDM — Tue, 13 Dec 2005 17:49:27 GMT

I have a function which will accept two variables:
type
dest

Then I have a bunch of variable pre-define such as:
cku=1234567890@txt.domain

The content of "type" will be "c".
The content of "dest" will be "ku"

So I want to display teh content of varible "cku" by concatenating the contents of "type" and "dest".

I've tried
echo "${${type}${dest}}" and other forms to try and get the content of "cku" displayed.

I will use this in a more complicated script which is why I'm not simply doing
echo "${cku}"

Can I use the content of 2 variables to build the name of the third variable and then display the content of that 3rd variable?

Cheers

Re: Use content of variables to get content of variable

Rodney Hills — Tue, 13 Dec 2005 17:56:50 GMT

Use the "eval" command.
x=${type}${dest}
eval echo \$$x

HTH

-- Rod Hills

Re: Use content of variables to get content of variable

James R. Ferguson — Tue, 13 Dec 2005 18:01:59 GMT

Hi Kevin:

I don't believe that the shell provides this kind of substitution. One sure wishes that it did.

Regards!

...JRF...

Re: Use content of variables to get content of variable

James R. Ferguson — Tue, 13 Dec 2005 18:06:37 GMT

Hi Rodney:

Why thanks :-))

/* No points for either of my posts, please! */

Regards!

...JRF...

Re: Use content of variables to get content of variable

OFC_EDM — Tue, 13 Dec 2005 18:13:42 GMT

Thanks Rodney.
The eval works on it's own.

But how can I plug that into a command?

Example

mailx -s " some text " eval echo \$$x

Where it would result in
mailx -s "some text" 1234567890@txt.domain

Re: Use content of variables to get content of variable

OFC_EDM — Tue, 13 Dec 2005 18:18:30 GMT

Got it working.

Will post solution and assign points ASAP

Re: Use content of variables to get content of variable

OFC_EDM — Wed, 14 Dec 2005 18:22:46 GMT

This is a shortened version of my much longer script but has the basic logic and shows how the eval statement allows using 2 variables to get the content of a 3rd variable.

--- start of script
cku="1234567890@txt.cellprovider.com"
eku="ku@emailaddress.com"

escalate() {
# format
# escalate type destination_name message

nf_dest="${1}${2}"
nf_body="$3"

#Purposely not using subject line in mailx
echo "${3}" | eval mailx \$${nf_dest}

}

# Sample calls to function
escalate c ku "test message to cell"
escalate e ku "test message to email"

--- end of script

Re: Use content of variables to get content of variable

OFC_EDM — Thu, 17 Apr 2008 11:16:35 GMT

see above