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variable declaration

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# 1  
Old 08-17-2010
variable declaration
Hi Guys,

What does this mean actually ? Can somebody give me any explanation ?

x=${x:=1}

Thanks
# 2  
Old 08-17-2010
From the (ksh) man page:

Code:
${parameter:=word}
              If  parameter is not set or is null then set it to word; the value of the parameter is then substituted.
              Positional parameters may not be assigned to in this way.

That's to say if x is empty or not defined, it's set to 1.
Last edited by Scott; 08-17-2010 at 05:12 AM.. Reason: Pasted wrong part of man page
# 3  
Old 08-17-2010
Thank Scott
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