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I've no idea how this command works and I've no test environment to see it's output

 
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# 1  
Old 01-04-2012
I've no idea how this command works and I've no test environment to see it's output
Code:
`echo $variable | cut -c$((${#variable}))-`

I know the working of echo,pipe and cut to some extent.

Thanks in advance .

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Last edited by radoulov; 01-04-2012 at 07:48 AM.. Reason: Code tags!
# 2  
Old 01-04-2012
It attempts to eval the final character of the contents of $variable... probably not what you intended
cut -c <int> - returns the characters from the position int to the end of the string

((${#variable})) the ${#variable} construct returns the index of the last character of $variable, wrapping it in the numeric eval brackets doubly ensures an integer is returned
This User Gave Thanks to Skrynesaver For This Post:
Ion_Shell
# 3  
Old 01-04-2012
Thank you ,
I can understand your explanation but one more query , what does '#' do ?
Does it return the index of the variable ?

---------- Post updated at 05:08 PM ---------- Previous update was at 04:57 PM ----------

Got it sorry .
Reason : Brain Dead .
Last edited by Ion_Shell; 01-04-2012 at 07:34 AM.. Reason: I need to know the usage of # before the variable .
 
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