NAME

       acl_extended_file, acl_extended_file_nofollow — test for information in ACLs by file name

LIBRARY

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

SYNOPSIS

       #include <sys/types.h>
       #include <acl/libacl.h>

       int
       acl_extended_file(const char *path_p);

       int
       acl_extended_file_nofollow(const char *path_p);

DESCRIPTION

       The acl_extended_file() function returns 1 if the file or directory referred to by the argument path_p is
       associated  with  an  extended access ACL, or if the directory referred to by path_p is associated with a
       default ACL. The function returns 0 if the file has neither an extended access ACL nor a default 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_file() function for a file
       object is 0, then ACLs define 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.

       acl_extended_file_nofollow() is identical to 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.

RETURN VALUE

       If successful, the acl_extended_file() function returns 1 if the file object referred to by path_p has an
       extended access ACL or a default ACL, and 0 if the file object referred  to  by  path_p  has  neither  an
       extended  access ACL nor a default 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_file() function returns -1 and sets  errno  to
       the corresponding value:

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

       [ENAMETOOLONG]     The length of the argument path_p is too long.

       [ENOENT]           The named object does not exist or the argument path_p points to an empty string.

       [ENOTDIR]          A component of the path prefix is not a directory.

       [ENOTSUP]          The  file  system  on  which the file identified by path_p 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).

SEE ALSO

       access(2), acl_get_file(3), acl(5)

AUTHOR

       Written by Andreas Gruenbacher <andreas.gruenbacher@gmail.com>.

Linux ACL                                        March 23, 2002                             ACL_EXTENDED_FILE(3)