Re: [mapfs-user] how to make a read-only fs writable?

[Albrecht G. <alb...@un...>]

On Thu, Nov 03, 2005 at 02:58:04AM -0800, Nathaniel Stahl wrote:
>=20
> Almost right.  You need to populate the View so that it refers to the=20
> files in the read/only filesystem.  For files in the View: directories=20
> represent themselves, data files contain a path to the host file that=20
> backs them (can be newline terminated or not) relative to the lookup=20
> root (root=3D) mount parameter, other special files (symbolic links,=20
> fifos, device nodes) just represent themselves.
>=20
> export VIEW=3D/path/to/mapfs/view
> export ROBASE=3D/path/to/robase
> export RELROBASE=3D/path/to/robase/from/mapfs/lookup/root
> cd $ROBASE
> find . -print0 | xargs -0 --replace=3DFOO sh -c "
> if [ -h FOO ]; then
>        cp -dp FOO $VIEW/FOO;
> elif [ -d FOO ]; then
>        mkdir $VIEW/FOO;
>        chown --reference=3DFOO $VIEW/FOO;
>        chmod --reference=3DFOO $VIEW/FOO;
> elif [ -f FOO ]; then
>        echo "$RELROBASE/FOO" > $VIEW/FOO;
>        chown --reference=3DFOO $VIEW/FOO;
>        chmod --reference=3DFOO $VIEW/FOO;
> else
>        cp -dp FOO $VIEW/FOO;
> fi"
>=20

ok, I'll try it.=20

Does it mean that the rw-tree will not automatically see files which
appear after the mapfs mount in the ro-tree? (this can not occur for a
cdrom but e.g. is possible for a readonly nfs mount)

Then I have to re-run the populate-view script?

Thanks for the quick answer

Albrecht


--=20
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