Simple SED Question


 
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# 1  
Old 11-06-2019
Simple SED Question

I don't understand this command behavior.
Code:
echo "abc" |sed 's/a/&_&/'

# 2  
Old 11-06-2019
The abc is passed to sed.
The sed substitutes a by a_a.
& is what matched, and the a matches an a.
This User Gave Thanks to MadeInGermany For This Post:
# 3  
Old 11-06-2019
But the output is a_abc
Why?
# 4  
Old 11-06-2019
The a becomes a_a
The following bc remains unchanged.
This User Gave Thanks to MadeInGermany For This Post:
# 5  
Old 11-06-2019
Thanks alot Sir.
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