SHMfs super magic

[Ulrich Drepper]

The shmfs currently sets the filesystem ID to zero (function
shm_statfs in ipc/shm.c).  This makes it hard/impossible to be 100%
sure the file one creates is on a shmfs filesystem.  Of course we
could define the super magic for the shmfs as 0 but please let there
be a constant SHMFS_SUPER_MAGIC.

The problem arises when in the libc I'm using open() and have to make
sure the file handle I get really belongs to a file on the shmfs and
not a file on a real filesystem.

Thanks,

-- 
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Ulrich Drepper  \    ,-------------------'   \  Sunnyvale, CA 94089 USA
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