How can I test if line is empty in shell script?

Posted by planetp on Stack Overflow See other posts from Stack Overflow or by planetp
Published on 2010-04-05T11:33:26Z Indexed on 2010/04/05 11:43 UTC
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Filed under:

shell-scripting

|

sh

I have a shell script like this:

cat file | while read line
do
    # run some commands using $line    
done

Now I need to check if the line contains any non-whitespace character ([\n\t ]), and if not, skip it. How can I do this?

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