LDAP_SERVER_SORT_OID

The LDAP_SERVER_SORT_OID control is used with an extended LDAP search function to instruct the server to sort the search results before returning it to the client application. The control specifies the sort key and sort behavior to be used by the server.

To use this control, format the control contents using the ldap_create_page_control function, or set the members of the LDAPControl structure as follows:

PWCHAR ldctl_oid = LDAP_SERVER_SORT_OID;
struct berval ldctl_value;
BOOLEAN ldctl_iscritical;

Members

ldctl_oid

LDAP_SERVER_SORT_OID, which is defined as "1.2.840.113556.1.4.473".

ldctl_value

Specifies a BER-encoded sequence of parameters that allows the application to specify the sort keys and matching rules (if any). In the berval structure, set bv_val to a pointer to the sequence containing the sort key data (see the following Remarks section), and set bv_len to the length of the sequence.

ldctl_iscritical

Can be TRUE or FALSE depending on whether sorting the search results is critical to your application.

Remarks

The Sort control is used with the extended search functions, such as ldap_search_ext, to specify the key or keys used by the server to sort the search results before returning them to the client. The ldctl_value field is set to the following BER-encoded sequence:

Sequence of Sequence {
  attributeType	OCTET STRING,
  orderingRule	 MatchingRuleID (optional),
  reverseOrder	 BOOLEAN
}

The ber_printf routine is used to create the sequence data. The sort key list sequence of sequences is in order of highest to lowest sort key precedence.

The various sequence fields are as follows:

Client programs are encouraged to use the various API calls such as ldap_create_sort_control, ldap_search_init_page, ldap_parse_result, ldap_parse_sort_control, etc., instead of manually creating and specifying the sort controls.

Requirements

Client: Included in Windows XP and Windows 2000 Professional.
Server: Included in Windows Server 2003 and Windows 2000 Server.
Redistributable: Requires Active Directory Client Extension on Windows NT 4.0 SP6a and Windows 95/98/Me.
Header: Declared in Winldap.h.

See Also

Data Structures, LDAPMessage, Using Controls