ldap_result - Wait for the result of an LDAP operation
OpenLDAP LDAP (libldap, -lldap)
int ldap_result( LDAP *ld, int msgid, int all,
struct timeval *timeout, LDAPMessage **result );
int ldap_msgfree( LDAPMessage *msg );
int ldap_msgtype( LDAPMessage *msg );
int ldap_msgid( LDAPMessage *msg );
The ldap_result() routine is used to wait for and return the result of
an operation previously initiated by one of the LDAP asynchronous oper‐
ation routines (e.g., ldap_search_ext(3), ldap_modify_ext(3), etc.).
Those routines all return -1 in case of error, and an invocation iden‐
tifier upon successful initiation of the operation. The invocation
identifier is picked by the library and is guaranteed to be unique
across the LDAP session. It can be used to request the result of a
specific operation from ldap_result() through the msgid parameter.
The ldap_result() routine will block or not, depending upon the setting
of the timeout parameter. If timeout is not a NULL pointer, it spec‐
ifies a maximum interval to wait for the selection to complete. If
timeout is a NULL pointer, the LDAP_OPT_TIMEOUT value set by
ldap_set_option(3) is used. With the default setting, the select
blocks indefinitely. To effect a poll, the timeout argument
should be a non-NULL pointer, pointing to a zero-valued timeval struc‐
ture. To obtain the behavior of the default setting, bypassing any
value set by ldap_set_option(3), set to -1 the tv_sec field of the
timeout parameter. See select(2) for further details.
If the result of a specific operation is required, msgid should be set
to the invocation identifier returned when the operation was initiated,
otherwise LDAP_RES_ANY or LDAP_RES_UNSOLICITED should be supplied to
wait for any or unsolicited response.
The all parameter, if non-zero, causes ldap_result() to return all
responses with msgid, otherwise only the next response is returned.
This is commonly used to obtain all the responses of a search opera‐
A search response is made up of zero or more search entries, zero or
more search references, and zero or more extended partial responses
followed by a search result. If all is set to 0, search entries will
be returned one at a time as they come in, via separate calls to
ldap_result(). If it's set to 1, the search response will only be
returned in its entirety, i.e., after all entries, all references, all
extended partial responses, and the final search result have been
Upon success, the type of the result received is returned and the
result parameter will contain the result of the operation; otherwise,
the result parameter is undefined. This result should be passed to the
LDAP parsing routines, ldap_first_message(3) and friends, for interpre‐
The possible result types returned are:
The ldap_msgfree() routine is used to free the memory allocated for
result(s) by ldap_result() or ldap_search_ext_s(3) and friends. It
takes a pointer to the result or result chain to be freed and returns
the type of the last message in the chain. If the parameter is NULL,
the function does nothing and returns zero.
The ldap_msgtype() routine returns the type of a message.
The ldap_msgid() routine returns the message id of a message.
ERRORSldap_result() returns -1 if something bad happens, and zero if the
timeout specified was exceeded. ldap_msgtype() and ldap_msgid() return
-1 on error.
SEE ALSOldap(3), ldap_first_message(3), select(2)ACKNOWLEDGEMENTS
OpenLDAP Software is developed and maintained by The OpenLDAP Project
<http://www.openldap.org/>. OpenLDAP Software is derived from Univer‐
sity of Michigan LDAP 3.3 Release.
OpenLDAP 2.4.39 2014/01/26 LDAP_RESULT(3)