file A
eebbbeeeeee
file B
4
Question is by file B and look into file A
output is b
awk -v v1=4 file B or something else
file A
eebbbeeeeee
file B
4
Question is by file B and look into file A
output is b
awk -v v1=4 file B or something else
awk -v v1=`cat file_b` '{print substr($1,v1,1)}' file_a
cut -c "$(cat fileB)" fileA