KornShell Error 0403-004 Specify a parameter with this command

Question

This KornShell code is throwing the following error:

test.ksh

#! /usr/bin/ksh

if [ ${fooVariable} = "" ]; then
    fooVariable="fooString"
fi

echo "${fooVariable}"

Error:

@:/tmp #./test.ksh
./test.ksh[3]: test: 0403-004 Specify a parameter with this command.

Why is this error being thrown and how to fix it?

Solution

Solution:

Put double quotes around variable.

test.ksh

#! /usr/bin/ksh

if [ "${fooVariable}" = "" ]; then
    fooVariable="fooString"
fi

echo "${fooVariable}"

Output:

@:/tmp #./test.ksh
fooString

Comments

[BarneySchmale]

Also you can use the special syntax that ksh provides for setting default values. var1_with_default=${var1:=bar}; echo $var1_with_default