acl_extended_file(3) — Linux manual page
ACL_EXTENDED_FILE(3) Library Functions Manual ACL_EXTENDED_FILE(3)
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
<sys/types.h> <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>.
COLOPHON
This page is part of the acl (manipulating access control lists)
project. Information about the project can be found at
http://savannah.nongnu.org/projects/acl. If you have a bug
report for this manual page, see
⟨http://savannah.nongnu.org/bugs/?group=acl⟩. This page was
obtained from the project's upstream Git repository
⟨git://git.savannah.nongnu.org/acl.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-04-25.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
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(which is not part of the original manual page), send a mail to
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