DHCP client/server

Hello, I'm developing one application on Linux machine. I need to make dhcp request two times using some shell script.
For first time I need to makean  request to dhcp server using dhclient to get IP address.
Question: How can  use dhclient to make such request and if client gets IP and how can I get that IP.
after second time, I again need to make dhcp request. This time I need other parameters also (like IP of Http server etc) along with IP address/subnet mask ..etc. IP address of HTTP server and other optional parameters are configured on dhcp server... I just need to make request to get them.
How can I achieve this.
Plz advise
pkgoyalAsked:
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NopiusConnect With a Mentor Commented:
>  I need to make dhcp request two times using some shell script.

Read:
man dhclient
man dhclient-script
man dhclient.conf

> For first time I need to makean  request to dhcp server using dhclient to get IP address.

Create /etc/dhclient-up-hooks file and make it executable.
It will look like:
#!/bin/bash
#
# Look here to see all variables you may use, like '$reason' or '$new_ip_address'
# also read man dhclient-script
env > /tmp/dhclient.txt

# That's a real code
case $reason in
  BOUND)
      echo My new IP address is $new_ip_address
      ;;
esac

To request new IP address (only then your dhclient-up-hook triggers), run as root:

# dhclient eth0

> after second time, I again need to make dhcp request. This time I need other parameters also (like IP of Http server etc) along with IP address/subnet mask ..etc. IP address of HTTP server and other optional parameters are configured on dhcp server...

Now add more logic inside your dhclient-up-hook
case $reason in
  BOUND)
      echo My new IP address is $new_ip_address
      ;;
  RENEW)
      echo Subnet: $new_subnet_mask
      ;;
esac
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