ifupdownでコーディングされています。
http://packages.debian.org/stable/ifupdown
ソースをダウンロードして
inet.cを作成します
関数dhcp_up()を確認してください:
static int dhcp_up(interface_defn *ifd, execfn *exec) {
{
if (!execute("[[ifconfig %iface% hw %hwaddress%]]", ifd, exec)) return 0;
}
if ( execable("/sbin/dhclient3") ) {
if (!execute("dhclient3 -pf /var/run/dhclient.%iface%.pid -lf /var/lib/dhcp3/dhclient.%iface%.leases %iface%", ifd, exec)) return 0;
}
else if ( execable("/sbin/dhclient") ) {
if (!execute("dhclient -v -pf /var/run/dhclient.%iface%.pid -lf /var/lib/dhcp/dhclient.%iface%.leases %iface%", ifd, exec)) return 0;
}
else if ( execable("/sbin/pump") && mylinuxver() >= mylinux(2,1,100) ) {
if (!execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]", ifd, exec)) return 0;
}
else if ( execable("/sbin/udhcpc") && mylinuxver() >= mylinux(2,2,0) ) {
if (!execute("udhcpc -n -p /var/run/udhcpc.%iface%.pid -i %iface% [[-H %hostname%]] [[-c %client%]]", ifd, exec)) return 0;
}
else if ( execable("/sbin/dhcpcd") ) {
if (!execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %client%]] [[-l %leasetime%]] %iface%", ifd, exec)) return 0;
}
return 1;
}