test Null variable


 
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# 1  
Old 11-24-2006
test Null variable

hi forum

i beginning with script and i want test un null variable in a schell
i just don t know the syntax here is a litle example

y=test
echo $y
unset y
echo $y (so here Y = Null)


if Y=Null

then
echo "y is null"
exit
fi



i have try
if [ !$y ]
but i have the error
test: argument expected
# 2  
Old 11-24-2006
i found it myself thank

if [ -z "$y" ]
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