The design of mdev (mini-udev for busybox).

Paul Fox pgf at
Mon Dec 5 17:50:12 UTC 2005

 > Rummage, rummage, rummage...
 > Having looked about your code, I believe I can say with some authority that 
 > you really, truly, _deeply_ need to look into initramfs.  You can have all 
 > that crud in the gzipped cpio archive built into the kernel image, and the 
 > kernel will extract it for you on boot.

can someone tell me why cpio was chosen for this?  wouldn't tar be
just as useful, and lower cost in "oh-no-not-another-required-tool" terms?

we're using the excellent inittar patches from:
for this purpose.  (and we have 2.6 patches if anyone's interested.)
having no more need for creating an initrd is nice at build time
(no need to be root), and at runtime: instead of setting up an
initrd, and then needing tmpfs in addition, the tarball goes
right into tmpfs, which gets mounted directly as root.

i realize initramfs solves a slightly different problem than this,
but i'm baffled by the cpio choice.

 paul fox, pgf at

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