|ACL_CHECK(3)||Library Functions Manual||ACL_CHECK(3)|
acl_check — check
an ACL for validity
Linux Access Control Lists library (libacl, -lacl).
function checks the ACL referred to by the argument
acl for validity.
The three required entries ACL_USER_OBJ, ACL_GROUP_OBJ, and ACL_OTHER must exist exactly once in the ACL. If the ACL contains any ACL_USER or ACL_GROUP entries, then an ACL_MASK entry is also required. The ACL may contain at most one ACL_MASK entry.
The user identifiers must be unique among all entries of type ACL_USER. The group identifiers must be unique among all entries of type ACL_GROUP.
If the ACL referred to by
acl is invalid,
returns a positive error code that indicates which type of error was
detected. The following symbolic error codes are defined:
- The ACL contains multiple entries that have a tag type that may occur at most once.
- The ACL contains multiple ACL_USER entries with the same user ID, or multiple ACL_GROUP entries with the same group ID.
- A required entry is missing.
- The ACL contains an invalid entry tag type.
function can be used to translate error codes to text messages.
In addition, if the pointer
last is not
assigns the number of the ACL entry at which the error was detected to the
value pointed to by last. Entries are numbered
starting with zero, in the order in which they would be returned by the
If successful, the
0 if the ACL referred to by
acl is valid, and a positive error code if the ACL is
invalid. Otherwise, a value of
-1 is returned and
the global variable errno is set to indicate the
If any of the following conditions occur, the
acl_check() function returns
-1 and sets errno to the
- The argument acl is not a valid pointer to an ACL.
This is a non-portable, Linux specific extension to the ACL manipulation functions defined in IEEE Std 1003.1e draft 17 (“POSIX.1e”, abandoned).
Written by Andreas Gruenbacher ⟨email@example.com⟩.
|March 23, 2002||Linux ACL|