.\" Access Control Lists manual pages
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.\" (C) 2002 Andreas Gruenbacher, <andreas.gruenbacher@gmail.com>
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.Dd March 23, 2002
.Dt ACL_EQUIV_MODE 3
.Os "Linux ACL"
.Sh NAME
.Nm acl_equiv_mode
.Nd check for an equivalent ACL
.Sh LIBRARY
Linux Access Control Lists library (libacl, \-lacl).
.Sh SYNOPSIS
.In sys/types.h
.In acl/libacl.h
.Ft int
.Fn acl_equiv_mode "acl_t acl" "mode_t *mode_p"
.Sh DESCRIPTION
The
.Fn acl_equiv_mode
function checks if the ACL pointed to by the argument
.Va acl
contains only the required ACL entries of tag types
ACL_USER_OBJ, ACL_GROUP_OBJ, and ACL_OTHER, and contains no
permissions other that ACL_READ, ACL_WRITE or ACL_EXECUTE.
If the ACL has this form, it can can be fully represented with
the traditional file permission bits, and is considered
equivalent with the traditional file permission bits.
.Pp
If
.Va acl
is an equivalent ACL and the pointer
.Va mode_p
is not
.Li NULL , 
the value pointed to by
.Va mode_p
is set to the value that defines the same owner, group and other
permissions as contained in
the ACL.
.Sh RETURN VALUE
On success, this function returns the value
.Li 0
if
.Va acl
is an equivalent ACL, and the value
.Li 1
if
.Va acl
is not an equivalent ACL. On error, the value
.Li -1
is returned, and
.Va errno
is set appropriately.
.Sh ERRORS
If any of the following conditions occur, the
.Fn acl_equiv_mode
function returns the value
.Li -1
and sets
.Va errno
to the corresponding value:
.Bl -tag -width Er
.It Bq Er EINVAL
The argument
.Va acl
is not a valid pointer to an ACL.
.El
.Sh STANDARDS
This is a non-portable, Linux specific extension to the ACL manipulation
functions defined in IEEE Std 1003.1e draft 17 (\(lqPOSIX.1e\(rq, abandoned).
.Sh SEE ALSO
.Xr acl_from_mode 3 ,
.Xr acl 5
.Sh AUTHOR
Written by
.An "Andreas Gruenbacher" Aq andreas.gruenbacher@gmail.com .