This is a rather unrelated subject and I apologize in advance, but I
figure there are enough php/*nix people on here to answer this.

I have finished writing a small script for m0n0wall but cannot fix a
small problem with its output.

I need to suppress output from
exec("dd if=/dev/zero of=tmp/mfsroot.bin bs=1k count=10240");

I have tried redirecting stdout to /dev/null to no avail, and cannot
find any "quiet" flags for dd.  I'm missing a simple trick, anyone know
it?

Thanks, and again apologies, I've googled for awhile now with
uninformative results.

--Michael I.