ACL_EXTENDED_FD - Online Linux Manual Page

Section : 3
Updated : March 23, 2002
Operating system : Linux ACL

NAME

acl_extended_fd

— test for information in the ACL by file descriptor

LIBRARY

Linux Access Control Lists library (libacl, −lacl).

SYNOPSIS

#include <sys/types.h

#include <acl/libacl.h>

int

acl_extended_fd

(

int

);

DESCRIPTION

The acl_extended_fd

(

) function returns

if the file identified by the argument

is associated with an extended access ACL. The function returns

if the file does not have an extended access ACL.

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 acl_extended_fd

(

) function for a file object is

, then the ACL defines no discretionary access rights other than those already defined by the traditional file permission bits.

Access to the file object may be further restricted by other mechanisms, such as Mandatory Access Control schemes. The access(2) system call can be used to check whether a given type of access to a file object would be granted.

RETURN VALUE

If successful, the acl_extended_fd

(

) function returns

if the file object identified by

has an extended access ACL, and

if the file object identified by

does not have an extended access ACL. Otherwise, the value

-1

is returned and the global variable

errno

is set to indicate the error.

ERRORS

If any of the following conditions occur, the acl_extended_fd

(

) function returns

-1

and sets

errno

to the corresponding value:

[

EBADF

]

The

argument is not a valid file descriptor.

[

ENOTSUP

]

The file system on which the file identified by

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

STANDARDS

This is a non-portable, Linux specific extension to the ACL manipulation functions defined in IEEE Std 1003.1e draft 17 (‟POSIX.1e”, abandoned).