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Test variables exist using a for loop

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# 1  
Old 01-10-2012
Test variables exist using a for loop
I am setting a number of variables in my script and I would like to test they exist by using a for loop.
e.g.
Code:
VAR1=abc
VAR2=xyz
for i in VAR1 VAR2; do
if [ -z $i ]; then
   echo Alert
fi
done

But of course the $i doesn't refer to the variable itself, rather to the strings VAR1 & VAR2.

Does anyone have any suggestions?

Thanks

Moderator's Comments:
Mod Comment Please use code tags when posting data and code samples, thank you.
Last edited by Franklin52; 01-10-2012 at 12:12 PM.. Reason: Please use code tags for data and code samples, thank you
# 2  
Old 01-10-2012
In BASH or new KSH you can do this:

Code:
for VAR in a b c d e f g
do
         if [ -z "${!VAR}" ]
         then
                 echo "$VAR not set"
                 exit 1
         fi
done

# 3  
Old 01-10-2012
Doesn't look like I have the new KSH, because I get the error "v[3]: "${!VAR}": bad substitution".

Ksh is my preferred (because familiar) shell.
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