Shell Programming and Scripting

cat bigfile
a
b
c
d potter
e
f pattern
g
h
i
j

grep -n 'p.tter' bigfile
4:d potter
6:f pattern

a=$(grep -n 'p.tter' bigfile)
a=${a%%:*}
echo $a
4

head -$a bigfile
a
b
c
d potter

tail +$((a+1)) bigfile
e
f pattern
g
h
i
j

csplit bigfile '/p.tter/+1'
15
20

cat xx00
a
b
c
d potter

cat xx01
e
f pattern
g
h
i
j

csplit bigfile '/p.tter/+1' '/p.tter/+1'
15
12
8

cat xx00
a
b
c
d potter

cat xx01
e
f pattern

cat xx02
g
h
i
j