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Check to see if string var is empty

 
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# 1  
Old 11-20-2009
Check to see if string var is empty
i have a veriable

set var1
set var2 = abcd

how can i check if var 1 is empty and if var 2 is not empty ???
# 2  
Old 11-20-2009
Code:
set var1
set var2 = abcd

if [ -z $var1 ] 
then
  echo 'var1 empty.'
fi

if [ -z $var2 ] 
then
  echo 'var2 empty.'
fi

# 3  
Old 11-24-2009
We must to put $var between quotes, otherwise an error will occur if $var is empty:
Code:
if [-z "$var"] ; then echo "var is empty" ; else echo "var = $var" ; fi

 
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