ACL_EXTENDED_FILE(3)    BSD Library Functions Manual    ACL_EXTENDED_FILE(3)

NAME         top

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

LIBRARY         top

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

SYNOPSIS         top

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

     acl_extended_file(const char *path_p);

     acl_extended_file_nofollow(const char *path_p);

DESCRIPTION         top

     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 mecha‐
     nisms, 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 inter‐
     rogated, not the file that it refers to.  Since symbolic links have no
     ACL themselves, the operation is supposed to fail on them.

RETURN VALUE         top

     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         top

     If any of the following conditions occur, the acl_extended_file() func‐
     tion 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

STANDARDS         top

     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         top

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

AUTHOR         top

     Written by Andreas Gruenbacher <>.

COLOPHON         top

     This page is part of the acl (manipulating access control lists)
     project.  Information about the project can be found at  If you have a bug report for
     this manual page, see ⟨⟩.
     This page was obtained from the project's upstream Git repository
     ⟨git://⟩ on 2018-10-29.  (At that time,
     the date of the most recent commit that was found in the repository was
     2018-06-18.)  If you discover any rendering problems in this HTML ver‐
     sion of the page, or you believe there is a better or more up-to-date
     source for the page, or you have corrections or improvements to the
     information in this COLOPHON (which is not part of the original manual
     page), send a mail to

Linux ACL                      March 23, 2002                      Linux ACL