How to write an OR statement

Shell Programming and Scripting
1

Hi all,
I want to check if the first or the second or the third argument of call to a shell script is empty.

How do i do that in a short way. I watched some examples and i believe
if [ .$1 = . ] checks if an argument is NULL.

If so, how can i add the checks for argument 2 and 3 in the statement?

Thanks in advance
Auke Quist

2

if [ .$1 = . ] || [ .$2 = . ] || [ .$3 = . ] ; then
echo "missing parameter"
fi