I just discovered VirtualBox’s guest control feature.

VboxManage.exe guestcontrol exec tophat \
    /bin/uname --arguments "-a" \
    --username sheldonh --password secret \
    --wait-for stdout

This logs into a virtualbox called tophat as user sheldonh, runs /bin/uname -a and returns the process output:

Linux tophat 2.6.35.13-91.fc14.x86_64 #1 SMP ...

Cute!

Tags: work