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.Dd April 2, 2004
.Dt VFS_SUSER 9
.Os
.Sh NAME
.Nm vfs_suser
.Nd check if credentials have superuser privileges for a mount point
.Sh SYNOPSIS
.In sys/param.h
.In sys/systm.h
.In sys/mount.h
.Ft int
.Fn vfs_suser "struct mount *mp" "struct thread *td"
.Sh DESCRIPTION
The
.Fn vfs_suser
function checks if the credentials given include superuser powers
for the given mount point.
It will check to see if the thread
passed in has the same credentials as the user that mounted the
file system.
If so, it returns 0, otherwise it returns what
.Xr priv_check 9
would have returned.
.Sh RETURN VALUES
The
.Fn vfs_suser
function returns 0 if the user has superuser powers and
.Er EPERM
otherwise.
This is the
.Em reverse logic
of some other implementations of
.Fn suser
in which a TRUE response indicates superuser powers.
.Sh SEE ALSO
.Xr chroot 2 ,
.Xr jail 2
.Sh HISTORY
The
.Fn vfs_suser
function was introduced in
.Fx 5.2 .
.Sh AUTHORS
This manual page was written by
.An Alfred Perlstein .