How to do a logical OR operation in shell scripting

Question

I am trying to do a simple condition check, but it doesn\'t seem to work.

If $# is equal to 0 or is greater than 1 then say he

Answer 1

If you are using the bash exit code status $? as variable, it's better to do this:

if [ $? -eq 4 -o $? -eq 8 ] ; then  
   echo "..."
fi

Because if you do:

if [ $? -eq 4 ] || [ $? -eq 8 ] ; then  

The left part of the OR alters the $? variable, so the right part of the OR doesn't have the original $? value.