UNIX for Dummies Questions & Answers

#!/usr/bin/env sh

# @(#) s1       Demonstrate sed insert (before) and append (after).

set -o nounset
echo
echo " (Versions displayed by local command.)"
version >/dev/null 2>&1 && version bash sed

cat >data1 <<EOF
one
two
three
four
five
EOF

echo
echo " Input data:"
cat data1

echo
echo " Results from sed:"
sed '/three/i \
2.1 \
2.2
4a \
4.1 \
4.2' data1

# See man sed, "Insert text".

exit 0

% ./s1

 (Versions displayed by local command.)
GNU bash 2.05b.0
GNU sed version 4.1.2

 Input data:
one
two
three
four
five

 Results from sed:
one
two
2.1
2.2
three
four
4.1
4.2
five