check if a variable is not affected

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03-17-2009

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check if a variable is not affected

Hi all,

to check that a variable is not empty, I usually do:

if [ -z "$a" ]; then...
or
if [ -n "$a" ]; then...

what if I have a serie of variables and want to do the same test on all of them. How to do this in a single if statement?

thank you

melanie_pfefer

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03-17-2009

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You can try using loops. For eg:

Code:

for i in <list of variables>
do
  if [ -z $i ] then
    do something;
  else
    do something;
done

HTH,

Regards,

Praveen

sunpraveen

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