Linux, dchp enabled info, dhcp server available

bit7 · 06-23-2006, 03:23 AM

Hi all,

i'm looking for some help to find a solution on this:
i would need to know from c, if the ip address of an interface (example eth0) has been dhcp assigned, and also if there is a simple way to know if a dhcp server is available on the local network, and what could be the next available dhcp ip.

It will be good even if this info are stored in some /proc pipe.

Infinite thanks, angelo

Tinkster · 06-23-2006, 10:14 PM

Quote:

Originally Posted by bit7

Hi all,

i'm looking for some help to find a solution on this:
i would need to know from c, if the ip address of an interface (example eth0) has been dhcp assigned,

Not from anything in /proc, but dhclient for instance will update
/etc/dhcpc/dhcpcd-eth0.info ... you can check the time-stamp in
the file and compare the current IP on the interface with the content
of the file aforementioned.

Quote:

Originally Posted by bit7

and also if there is a simple way to know if a dhcp server is available on the local network,

Send a dhcp request :} and see if anything answers.

Quote:

Originally Posted by bit7

and what could be the next available dhcp ip.

Only if you're on the server. The server doesn't send out lists of
"next free IPs" all the time.

Cheers,
Tink