growfs question

[Jeff LaMarche]

Okay, I've got FreeBSD 4.8-Stable running, and I've run out of room on /

I've looked around, and I think (in theory) that I can use growfs to 
increase the size of / since the contiguous slice is /tmp, from which I 
can sacrifice some space.

Filesystem  1K-blocks    Used    Avail Capacity  Mounted on
/dev/ad0s1a    128990  127684    -9012   108%    /
/dev/ad0s1f    257998    1254   236106     1%    /tmp
/dev/ad0s1g  18359694 5072672 11818248    30%    /usr
/dev/ad0s1e    257998    8384   228976     4%    /var
procfs              4       4        0   100%    /proc

Problem is, I'm not quite sure how to do it, and scared of messing up 
my system in the process. Has anyone attempted something similar?

TIA
Jeff LaMarche