NAME

       acl_check — check an ACL for validity

LIBRARY

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

SYNOPSIS

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

       int
       acl_check(acl_t acl, int *last);

DESCRIPTION

       The acl_check() 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, acl_check() returns a positive error code that indicates which
       type of error was detected.  The following symbolic error codes are defined:

       ACL_MULTI_ERROR       The ACL contains multiple entries that have a tag type that may occur at most once.

       ACL_DUPLICATE_ERROR   The ACL contains multiple ACL_USER entries with  the  same  user  ID,  or  multiple
                             ACL_GROUP entries with the same group ID.

       ACL_MISS_ERROR        A required entry is missing.

       ACL_ENTRY_ERROR       The ACL contains an invalid entry tag type.

       The acl_error() function can be used to translate error codes to text messages.

       In  addition,  if  the pointer last is not NULL, acl_check() 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 acl_get_entry() function.

RETURN VALUE

       If  successful, the acl_check() function returns 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 error.

ERRORS

       If  any  of  the  following  conditions  occur, the acl_check() function returns -1 and sets errno to the
       corresponding value:

       [EINVAL]           The argument acl is not a valid pointer to an ACL.

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

       acl_valid(3), acl(5)

AUTHOR

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

Linux ACL                                        March 23, 2002                                     ACL_CHECK(3)