test Null variable

kykyboss · #1 (**permalink**) 11-24-2006

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

kykyboss · #2 (**permalink**) 11-24-2006

i found it myself thank

if [ -z "$y" ]

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