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LDAP(3)                    Library Functions Manual                    LDAP(3)

       ldap - OpenLDAP Lightweight Directory Access Protocol API

       OpenLDAP LDAP (libldap, -lldap)

       #include <ldap.h>

       The Lightweight Directory Access Protocol (LDAP) (RFC 4510) provides
       access to X.500 directory services.  These services may be stand-alone
       or part of a distributed directory service.  This client API supports
       LDAP over TCP (RFC 4511), LDAP over TLS/SSL, and LDAP over IPC (UNIX
       domain sockets).  This API supports SASL (RFC 4513) and Start TLS (RFC
       4513) as well as a number of protocol extensions.  This API is loosely
       based upon IETF/LDAPEXT C LDAP API draft specification, a (orphaned)
       work in progress.

       The OpenLDAP Software package includes a stand-alone server in
       slapd(8), various LDAP clients, and an LDAP client library used to
       provide programmatic access to the LDAP protocol. This man page gives
       an overview of the LDAP library routines.

       Both synchronous and asynchronous APIs are provided.  Also included are
       various routines to parse the results returned from these routines.
       These routines are found in the -lldap library.

       The basic interaction is as follows.  A session handle is created using
       ldap_initialize(3) and set the protocol version to 3 by calling
       ldap_set_option(3).  The underlying session is established first
       operation is issued.  This would generally be a Start TLS or Bind
       operation, or a Search operation to read attributes of the Root DSE.  A
       Start TLS operation is performed by calling ldap_start_tls_s(3).  A
       LDAP bind operation is performed by calling ldap_sasl_bind(3) or one of
       its friends.  A Search operation is performed by calling
       ldap_search_ext_s(3) or one of its friends.

       Subsequently, additional operations are performed by calling one of the
       synchronous or asynchronous routines (e.g., ldap_compare_ext_s(3) or
       ldap_compare_ext(3) followed by ldap_result(3)).  Results returned from
       these routines are interpreted by calling the LDAP parsing routines
       such as ldap_parse_result(3).  The LDAP association and underlying
       connection is terminated by calling ldap_unbind_ext(3).  Errors can be
       interpreted by calling ldap_err2string(3).

LDAP versions
       This library supports version 3 of the Lightweight Directory Access
       Protocol (LDAPv3) as defined in RFC 4510.  It also supports a variant
       of version 2 of LDAP as defined by U-Mich LDAP and, to some degree, RFC
       1777.  Version 2 (all variants) are considered obsolete.  Version 3
       should be used instead.

       For backwards compatibility reasons, the library defaults to version 2.
       Hence, all new applications (and all actively maintained applications)
       should use ldap_set_option(3) to select version 3.  The library manual
       pages assume version 3 has been selected.

       All character string input/output is expected to be/is UTF-8 encoded
       Unicode (version 3.2).

       Distinguished names (DN) (and relative distinguished names (RDN) to be
       passed to the LDAP routines should conform to RFC 4514 UTF-8 string

       Search filters to be passed to the search routines are to be
       constructed by hand and should conform to RFC 4515 UTF-8 string

       LDAP URLs to be passed to routines are expected to conform to RFC 4516
       format.  The ldap_url(3) routines can be used to work with LDAP URLs.

       LDAP controls to be passed to routines can be manipulated using the
       ldap_controls(3) routines.

       Results obtained from the search routines can be output by hand, by
       calling ldap_first_entry(3) and ldap_next_entry(3) to step through the
       entries returned, ldap_first_attribute(3) and ldap_next_attribute(3) to
       step through an entry's attributes, and ldap_get_values(3) to retrieve
       a given attribute's values.  Attribute values may or may not be

       Also provided are various utility routines.  The ldap_sort(3) routines
       are used to sort the entries and values returned via the ldap search

       A number of interfaces are now considered deprecated.  For instance,
       ldap_add(3) is deprecated in favor of ldap_add_ext(3).  Deprecated
       interfaces generally remain in the library.  The macro LDAP_DEPRECATED
       can be defined to a non-zero value (e.g., -DLDAP_DEPRECATED=1) when
       compiling program designed to use deprecated interfaces.  It is
       recommended that developers writing new programs, or updating old
       programs, avoid use of deprecated interfaces.  Over time, it is
       expected that documentation (and, eventually, support) for deprecated
       interfaces to be eliminated.

       Also included in the distribution is a set of lightweight Basic
       Encoding Rules routines.  These routines are used by the LDAP library
       routines to encode and decode LDAP protocol elements using the
       (slightly simplified) Basic Encoding Rules defined by LDAP.  They are
       not normally used directly by an LDAP application program except in the
       handling of controls and extended operations.  The routines provide a
       printf and scanf-like interface, as well as lower-level access.  These
       routines are discussed in lber-decode(3), lber-encode(3),
       lber-memory(3), and lber-types(3).

       ldap_initialize(3)  initialize the LDAP library without opening a
                           connection to a server

       ldap_result(3)      wait for the result from an asynchronous operation

       ldap_abandon_ext(3) abandon (abort) an asynchronous operation

       ldap_add_ext(3)     asynchronously add an entry

       ldap_add_ext_s(3)   synchronously add an entry

       ldap_sasl_bind(3)   asynchronously bind to the directory

       ldap_sasl_bind_s(3) synchronously bind to the directory

       ldap_unbind_ext(3)  synchronously unbind from the LDAP server and close
                           the connection

       ldap_unbind(3) and ldap_unbind_s(3) are
                           equivalent to ldap_unbind_ext(3)

       ldap_memfree(3)     dispose of memory allocated by LDAP routines.

       ldap_compare_ext(3) asynchronously compare to a directory entry

                           synchronously compare to a directory entry

       ldap_delete_ext(3)  asynchronously delete an entry

                           synchronously delete an entry

       ld_errno(3)         LDAP error indication

       ldap_errlist(3)     list of LDAP errors and their meanings

       ldap_err2string(3)  convert LDAP error indication to a string

                           asynchronously perform an arbitrary extended

                           synchronously perform an arbitrary extended

                           return first attribute name in an entry

                           return next attribute name in an entry

       ldap_first_entry(3) return first entry in a chain of search results

       ldap_next_entry(3)  return next entry in a chain of search results

                           return number of entries in a search result

       ldap_get_dn(3)      extract the DN from an entry

                           return an attribute's values with lengths

                           free memory allocated by ldap_get_values_len(3)

                           return number of values

       ldap_modify_ext(3)  asynchronously modify an entry

                           synchronously modify an entry

       ldap_mods_free(3)   free array of pointers to mod structures used by

       ldap_rename(3)      asynchronously rename an entry

       ldap_rename_s(3)    synchronously rename an entry

       ldap_msgfree(3)     free results allocated by ldap_result(3)

       ldap_msgtype(3)     return the message type of a message from

       ldap_msgid(3)       return the message id of a message from

       ldap_search_ext(3)  asynchronously search the directory

                           synchronously search the directory

       ldap_is_ldap_url(3) check a URL string to see if it is an LDAP URL

       ldap_url_parse(3)   break up an LDAP URL string into its components

                           sort a list of search results

       ldap_sort_values(3) sort a list of attribute values

                           case insensitive string comparison

       ldap.conf(5), slapd(8),
       draft-ietf-ldapext-ldap-c-api-xx.txt <http://www.ietf.org>

       OpenLDAP Software is developed and maintained by The OpenLDAP Project
       <http://www.openldap.org/>.  OpenLDAP Software is derived from the
       University of Michigan LDAP 3.3 Release.

       These API manual pages are loosely based upon descriptions provided in
       the IETF/LDAPEXT C LDAP API Internet Draft, a (orphaned) work in

OpenLDAP 2.4.50                   2020/04/28                           LDAP(3)