unix - Error while passing variables in sed -


my script:

while read start_val end_value = "$start_val+10" | bc  sed -n '"$start_value","$end_value"d'  <file> done < in_file

actually want print lines of file using data taken input file doing calculations.

it because variables not expanded inside of single quotes ('). try instance

echo '$home'

vs 

echo "$home"

the same goes example single quotes after sed.


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