topic Re: bash: unbound variable in Operating System - HP-UX

bash: unbound variable

Greg B_1 — Fri, 20 Dec 2002 03:36:31 GMT

when I execute a shell script containing:
(and expecting to get one of the two statements echoed)

if [ $greg = "test" ]; then
echo "greg equal to test"
else
echo "greg not equal to test"
fi

I get:
bash: greg: unbound variable

Can anyone explain what's the deal there?

Re: bash: unbound variable

RAC_1 — Fri, 20 Dec 2002 04:02:34 GMT

how shell is supposed to find greg? you are defining it anywhere in the script.

It should be
grep=test
if [ $greg = "test" ]; then
echo "greg equal to test"
else
echo "greg not equal to test"
fi

This will give greg eqal to test

Re: bash: unbound variable

Deepak Extross — Fri, 20 Dec 2002 04:21:34 GMT

An unbound variable is one that has not been defined.

Try checking for existence of the variable using the test -z option before doing any comparison:
if [ -z $greg ]; then
....

Re: bash: unbound variable

T G Manikandan — Fri, 20 Dec 2002 04:28:23 GMT

///define greg//

greg=test
or
greg=test1

if [ $greg = "test" ]
then
echo "greg equal to test"
else
echo "greg not equal to test"
fi