Very Computer

I am trying to reference an environment variable from within an
environment variable.

    HOME=/home/paul
    x=HOME
    echo $"$x"

    gives me $HOME and not /home/paul
or
    HOME=/home/paul
    x=\$HOME
    echo $x

    gives me $HOME and not /home/paul

I could write a c program that would use getenv recursively, but it
would me more aesthetically pleasing to use a (simple ?) shell command.
Is there anything I'm missing, or am I attempting the impossible ?

I am using ksh on HP-UX 10.20

Please email any thoughts as well as posting them.  Thanks

Paul Graves

EDS Electronic Commerce
Cheadle, Cheshire, UK

Try this

     HOME=/home/paul
     x=$HOME
     echo $x

good luck

Minh

Also, your question looks suspiciously as if a look at
    man eval
would help...
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I'm using bash under HP-UX 10.20.

#!/home/tellkamp/bin/bash
if [ -f /usr/local/bin/e4rc ] ; then
   . /usr/local/bin/e4rc &>/dev/null            # set environment
else
   exit 1
fi

DIR=$(eval echo \${$1})                        # $1 is smthng like HOME
# now DIR is the string given in $1, it can be expanded wih ${DIR}

echo -e "building in ${DIR} on host \n$(banner ${HOST})\n"
cd ${DIR} ; make
exit $?

--
Jan Tellkamp
Flensburg, 06. August 1997

|> DIR=$(eval echo \${$1})                        # $1 is smthng like HOME

Another Useless Use of Command Substitution.

eval DIR=\${$1}
--
Andreas Schwab                                      "And now for something

Jan
Flensburg, 08. August 1997

Quote:> > I am trying to reference an environment variable from within an
> > environment variable.
> >     HOME=/home/paul
> >     x=HOME
> >     echo $"$x"
> >     gives me $HOME and not /home/paul
> > or
> >     HOME=/home/paul
> >     x=\$HOME
> >     echo $x
> >     gives me $HOME and not /home/paul

HOME=/home/paul
x=$HOME
echo $x

Why make it simple, eh? ;-)

Sabina

ps: basic understandings of $ in shell - it 'evaluates' variable
                        and =          - simple assignment