Convert string into integer in bash script - “Leading Zero” number error

Question

In a text file, test.txt, I have the next information:

sl-gs5 desconnected Wed Oct 10 08:00:01 EDT 2012 1001

I want to extract the hour of

Answer 1

Here's an easy way, albeit not the prettiest way to get an int value for a string.

hour=`expr $hour + 0`

Example

bash-3.2$ hour="08"
bash-3.2$ hour=`expr $hour + 0`
bash-3.2$ echo $hour
8