com interface comfiguration in linux

gistfile1.txt

sed -i -e '/splash/a\serial --unit=0 --speed=115200 --word=8 --parity=no --stop=1 terminal --timeout=5 serial console' grub.conf
sed -i -e '/vmlinuz/ s/$/& console=tty0 console=ttyS0,115200n8/' grub.conf
echo 'ttyS0' >> /etc/securetty
cat >> /etc/init/ttyS0.conf  <<EOF
start on runlevel [345]
stop on runlevel [S016]

respawn
instance  /dev/ttyS0
exec /sbin/agetty   ttyS0  115200 vt100-nav
EOF