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With that logic this echoes "echo". Question about echo!


 
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# 1  
Old 11-11-2010
Hammer & Screwdriver With that logic this echoes "echo". Question about echo!

Code:
echo `echo `

doesn't echoes anything. And it's logic. But
Code:
echo `echo `echo ` `

does echoes "echo". What's the logic of it? the `echo `echo ` inside of the whole (first) echo, echoes nothing, so the first echo have to echo nothing but echoes "echo"

(too much echoing :P)Smilie
# 2  
Old 11-11-2010
That is because backticks have to be escaped if you nest them:
Code:
echo `echo \`echo \` `

You do not need to with the more modern $(..) command substitution construct:
Code:
 echo $(echo $(echo))

# 3  
Old 11-11-2010
Thx, it seems interesting Smilie

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