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how to use ` inside a `

 
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# 1  
Old 12-04-2011
how to use ` inside a `
For example, as of now i am doing in 2 lines:

Code:
a=`cat $1|wc -l`
b=`expr $a  - 1`

How i can above into single line?
Code:
b=`expr `cat $1|wc -l` - 1`

The above code doesn't work.
why i am not able to use multiple `s in single line.
Whats the alternative for this?
Thanks
# 2  
Old 12-04-2011
You need to escape the inner ` (like \`).

If you use the $(...) syntax for command substitution, you don't need to escape anything.

Code:
b=$(($(wc -l < $1) - 1))

This User Gave Thanks to Scott For This Post:
pandeesh
# 3  
Old 12-04-2011
Thanks man!
 
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