hello everyone,
i am running linux(debian, but doesn't really matter) on an arm processor.
i need to be able from an application on that board to change the ip.
now the call for a static ip is easy
ill just to a system() call as:

system("ifconfig eth0:1 192.168.1.156");

but if i want, at runtime (ie without needing to write code that tweaks /etc/network/interfaces)
to change from static to dynamic ip. how will i do that?

basically, if there is something like

system("ifconfig eth0:1 dchpd start"); //or smth like that...

that would be awesome..
but is there anyway i can use ifconfig to instruct the system to take addresses from the dhcp?
thank you for your help
nass
you get

What about running "dhcpcd eth0" or "dhclient eth0" (I'm not sure which Debian provides)?

Try dhclient, that is the daemon process responsible for configuring your interface(s) by using the dynamic host configuration protocol, or the bootp protocol.

man dhclient will tell you all about it, or if you are using kde, run command: #dhclient

Best regards

Andy

Moved to Linux-General as this isn't a Slackware problem.

yes, i see.
so if i am to switch from static to dynamic (and provided i have a static in /etc/network/interfaces) during a startup script,

i should NOT run:
ifconfig eth0:1 192.18.0.2
route del default gw 192.168.0.1
route add default gw 192.168.0.1

instead, i should run

dhclieth eth0:1 #or however else it should be called

right?
nass

Not sure you need to delete routes, unless you configured those statically as well.

The dhclient takes care of configuring IP address, DNS servers, and Gateway, which means that it will add the appropriate route entries too.

Try for yourself from the console:

ifdown eth0
dhclient eth0

And see what happens