I was looking around on the internet to find if there was already a way to time a certain part of an executable/script to see how long that part takes, but all that I find is more for outside the file. So I want to input a line that starts a timer and at the end of the part stops the timer and shows me the elapsed time, not the whole thing but just a part.

example:

  #!/bin/sh

    IPTABLES="/sbin/iptables"

    BLOCKEDIPS_XS=/root/iptables/iptables/blockxs.zone

$IPTABLES -F

$IPTABLES -F INPUT

$IPTABLES -F OUTPUT

$IPTABLES --delete-chain

$IPTABLES -F FORWARD

$IPTABLES -F -t mangle

$IPTABLES -F -t nat

$IPTABLES -X

timer start

/bin/egrep -v "^#|^$" $BLOCKEDIPS_XS | while IFS= read -r ip

do

    # Append everything to droplist

    $IPTABLES -A droplist -i eth0 -s $ip -j LOG --log-prefix " Drop IP List blockxs "

    $IPTABLES -A droplist -i eth0 -s $ip -j DROP

done <"$BLOCKEDIPS_XS"

timer stops, shows elapsed time