acl_valid(3) — Linux manual page


ACL_VALID(3)             Library Functions Manual           ACL_VALID(3)

NAME         top

       acl_valid — validate an ACL

LIBRARY         top

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

SYNOPSIS         top

       <sys/types.h> <sys/acl.h> int acl_valid(acl_t acl)

DESCRIPTION         top

       The acl_valid() 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.

RETURN VALUE         top

       The acl_valid() function returns the value 0 if successful;
       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_valid()
       function returns -1 and sets errno to the corresponding value:

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

                          The argument acl does not point to a valid

                          One or more of the required ACL entries is not
                          present in acl.

                          The ACL contains entries that are not unique.

STANDARDS         top

       IEEE Std 1003.1e draft 17 (“POSIX.1e”, abandoned)

SEE ALSO         top

       acl_check(3), acl_set_file(3), acl(5)

AUTHOR         top

       Derived from the FreeBSD manual pages written by Robert N M
       Watson <>, and adapted for Linux by Andreas
       Gruenbacher <>.

COLOPHON         top

       This page is part of the acl (manipulating access control lists)
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Linux ACL                    March 23, 2002                 ACL_VALID(3)