How to determine if a bash variable is empty?

Posted by Brent on Server Fault See other posts from Server Fault or by Brent
Published on 2009-05-12T17:54:48Z Indexed on 2010/05/20 21:02 UTC
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bash

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scripting

What is the best way to determine if a variable in bash contains ""?

I have heard it recommended that I do if [ "x$variable" = "x" ]

Is that the correct way? (there must be something more straightforward)

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