# ldap

## NAME



           ldap - OpenLDAP Lightweight Directory Access Protocol API
    


## LIBRARY



           OpenLDAP LDAP (libldap, -lldap)
    


## SYNOPSIS



           **#include <ldap.h>**
    


## DESCRIPTION



           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.
    


## INPUT and OUTPUT PARAMETERS



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


## DISPLAYING RESULTS



           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 displayable.
    


## UTILITY ROUTINES



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


## DEPRECATED INTERFACES



           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.
    


## BER LIBRARY



           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).
    


## INDEX



           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
    
           ldap_compare_ext_s(3)
                  synchronously compare to a directory entry
    
           ldap_delete_ext(3)
                  asynchronously delete an entry
    
           ldap_delete_ext_s(3)
                  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
    
           ldap_extended_operation(3)
                  asynchronously perform an arbitrary extended operation
    
           ldap_extended_operation_s(3)
                  synchronously perform an arbitrary extended operation
    
           ldap_first_attribute(3)
                  return first attribute name in an entry
    
           ldap_next_attribute(3)
                  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
    
           ldap_count_entries(3)
                  return number of entries in a search result
    
           ldap_get_dn(3)
                  extract the DN from an entry
    
           ldap_get_values_len(3)
                  return an attribute's values with lengths
    
           ldap_value_free_len(3)
                  free memory allocated by ldap_get_values_len(3)
    
           ldap_count_values_len(3)
                  return number of values
    
           ldap_modify_ext(3)
                  asynchronously modify an entry
    
           ldap_modify_ext_s(3)
                  synchronously modify an entry
    
           ldap_mods_free(3)
                  free array of pointers to mod structures used by
                  ldap_modify_ext(3)
    
           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_result(3)
    
           ldap_msgid(3)
                  return the message id of a message from ldap_result(3)
    
           ldap_search_ext(3)
                  asynchronously search the directory
    
           ldap_search_ext_s(3)
                  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
    
           ldap_sort_entries(3)
                  sort a list of search results
    
           ldap_sort_values(3)
                  sort a list of attribute values
    
           ldap_sort_strcasecmp(3)
                  case insensitive string comparison
    


## ACKNOWLEDGEMENTS



           **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 progress.
    


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