Re: ownership/permissions of cpio initrd

["Horst H. von Brand" <vonbrand@inf.utfsm.cl>]

Marty Leisner <linux@rochester.rr.com> wrote:
> I'm working on an embedded system with the 2.6 kernel -- cpio
> initrd was a new feature I'm looking at (and very welcome).
> 
> The major advantage I see is you don't have MAKE a filesystem
> on the build host (doing cross development).  So you don't have
> to be root.

> But its "useful" to change permissions/ownership of the initrd
> files at times...

> Since a cpio is just a userspace created string of bits, I suppose
> you can apply a set of ownership/permissions to files IN the archive
> by playing with the bits...

The easy way out is to unpack the initrd, fix permissions, and repack. That
requires root, though (it creates devices).

> Does such a tool exist?  Comments?  Seems very useful in order to
> avoid being root...

I'd use sudo(1) + specially cooked commands to unpack/pack an initrd. It is
a bit more work, but gives you extra flexibility (i.e., not just futzing
around with permissions, can also add/replace/edit/rename/delete files, ...
using bog standard tools).
-- 
Dr. Horst H. von Brand                   User #22616 counter.li.org
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