SIGTERM is not killing udhcpc

[Bryan Evenson]

I'm using Busybox version 1.20.2, and I noticed something odd with udhcpc.  When I bring down a network interface ("ifdown eth0") the udhcpc process for that interface keeps running.  I thought there might be something wrong with the ifupdown script to kill the udhcpc process, so I tried killing the udhcpc process by hand but it kept running.  I had to do "kill -9" to kill udhcpc; standard kill signal of SIGTERM didn't kill it.

Anyone else notice behavior like this, or is this an oddity of my build?  The udhcpc command as it shows up in the process list is "udhcpc -R -n -p /var/run/udhcpc.eth0.pid -i eth0".  It also just shows up as sleeping, so I'd think a SIGTERM would kill it.

Thanks,
Bryan