Mastering Linux Shell Scripting - Second Edition

Chapter 5

1. By using ((:

#!/bin/bashnum=$(( 25 - 8 ))echo $num

2. The problem is with the space in the filename. To fix it, put the filename between quotes:

$ rm "my file"

3. There is no dollar sign before the parentheses:

#!/bin/basha=$(( 8 + 4 ))echo $a