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.\" (C) 2002 Andreas Gruenbacher, <a.gruenbacher@bestbits.at>

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.Dd March 23, 2002

.Dt ACL_EXTENDED_FILE 3

.Os "Linux ACL"

.Sh NAME

.Nm acl_extended_file, acl_extended_file_nofollow

.Nd test for information in ACLs by file name

.Sh LIBRARY

Linux Access Control Lists library (libacl, \-lacl).

.Sh SYNOPSIS

.In sys/types.h

.In acl/libacl.h

.Ft int

.Fn acl_extended_file "const char *path_p"

.Ft int

.Fn acl_extended_file_nofollow "const char *path_p"

.Sh DESCRIPTION

The

.Fn acl_extended_file

function returns

.Li 1

if the file or directory referred to by the argument

.Va path_p

is associated with an extended access ACL, or if the directory referred to by

.Va path_p

is associated with a default ACL. The function returns

.Li 0

if the file has neither an extended access ACL nor a default ACL.

.Pp

An extended ACL is an ACL that contains entries other than the three

required entries of tag types ACL_USER_OBJ, ACL_GROUP_OBJ and ACL_OTHER.

If the result of the

.Fn acl_extended_file

function for a file object is

.Li 0 ,

then ACLs define no discretionary access rights other than those

already defined by the traditional file permission bits.

.Pp

Access to the file object may be further restricted by other

mechanisms, such as Mandatory Access Control schemes. The

.Xr access 2

system call can be used to check whether a given type of access to a file

object would be granted.

.Pp

.Fn acl_extended_file_nofollow

is identical to

.Fn acl_extended_file ,

except in the case of a symbolic link, where the link itself is interrogated,

not the file that it refers to.  Since symbolic links have no ACL themselves,

the operation is supposed to fail on them.

.Sh RETURN VALUE

If successful, the

.Fn acl_extended_file

function returns

.Li 1

if the file object referred to by

.Va path_p

has an extended access ACL or a default ACL, and

.Li 0

if the file object referred to by

.Va path_p

has neither an extended access ACL nor a default ACL. Otherwise, the value

.Li -1

is returned and the global variable

.Va errno

is set to indicate the error.

.Sh ERRORS

If any of the following conditions occur, the

.Fn acl_extended_file

function returns

.Li -1

and sets

.Va errno

to the corresponding value:

.Bl -tag -width Er

.It Bq Er EACCES

Search permission is denied for a component of the path prefix.

.It Bq Er ENAMETOOLONG

The length of the argument

.Va path_p

is too long.

.It Bq Er ENOENT

The named object does not exist or the argument

.Va path_p

points to an empty string.

.It Bq Er ENOTDIR

A component of the path prefix is not a directory.

.It Bq Er ENOTSUP

The file system on which the file identified by

.Va path_p

is located does not support ACLs, or ACLs are disabled.

.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 access 2 ,

.Xr acl_get_file 3 ,

.Xr acl 5

.Sh AUTHOR

Written by

.An "Andreas Gruenbacher" Aq a.gruenbacher@bestbits.at .