Using wpa_cli and busybox udhcpc

Busybox udhcpc execution on gentoo

/bin/busybox udhcpc -x hostname:localhost \
--interface=wlan0 \
--now --script=/lib/netifrc/sh/udhcpc-hook.sh \
--pidfile=/run/udhcpc-wlan0.pid

Switch to another configured network

~ $ sudo wpa_cli
> list_networks
network id / ssid / bssid / flags
0       network1   any     [DISABLED]
1       network2   any     [DISABLED]
> select_network 1

Allow wpa_supplicant to connect to any of the networks in the configuration file (this is the default).

> enable_network 0
> enable_network 1

See the help in wpa_cli for more detail.

Renewing the DHCP Lease

~ $ kill -SIGUSR1 `cat /run/udhcpc-wlan0.pid`

Or, if you don't like backticks (they are discouraged):

~ $ kill -SIGUSR1 $(cat /run/udhcpc-wlan0.pid)