CLDAP_SEARCH_S(3LDAP)CLDAP_SEARCH_S(3LDAP)NAMEcldap_search_s - connectionless LDAP search
SYNOPSIS
cc[ flag... ] file... -lldap[ library... ]
#include <lber.h>
#include <ldap.h>
int cldap_search_s(LDAP *ld, char *base, int scope, char *filter,
char *attrs, int attrsonly, LDAPMessage **res, char *logdn);
DESCRIPTION
The cldap_search_s() function performs an LDAP search using the Connec‐
tionless LDAP (CLDAP) protocol.
cldap_search_s() has parameters and behavior identical to that of
ldap_search_s(3LDAP), except for the addition of the logdn parameter.
logdn should contain a distinguished name to be used only for logging
purposed by the LDAP server. It should be in the text format described
by RFC 1779, A String Representation of Distinguished Names.
Retransmission Algorithm
cldap_search_s() operates using the CLDAP protocol over udp(7P). Since
UDP is a non-reliable protocol, a retry mechanism is used to increase
reliability. The cldap_setretryinfo(3LDAP) function can be used to set
two retry parameters: tries, a count of the number of times to send a
search request and timeout, an initial timeout that determines how long
to wait for a response before re-trying. timeout is specified seconds.
These values are stored in the ld_cldaptries and ld_cldaptimeout mem‐
bers of the ld LDAP structure, and the default values set in
ldap_open(3LDAP) are 4 and 3 respectively. The retransmission algorithm
used is:
Step 1
Set the current timeout to ld_cldaptimeout seconds, and the
current LDAP server address to the first LDAP server found
during the ldap_open(3LDAP) call.
Step 2
Send the search request to the current LDAP server address.
Step 3
Set the wait timeout to the current timeout divided by the
number of server addresses found during ldap_open(3LDAP) or
to one second, whichever is larger. Wait at most that long
for a response; if a response is received, STOP. Note that
the wait timeout is always rounded down to the next lowest
second.
Step 4
Repeat steps 2 and 3 for each LDAP server address.
Step 5
Set the current timeout to twice its previous value and
repeat Steps 2 through 5 a maximum of tries times.
EXAMPLES
Assume that the default values for tries and timeout of 4 tries and 3
seconds are used. Further, assume that a space-separated list of two
hosts, each with one address, was passed to cldap_open(3LDAP). The pat‐
tern of requests sent will be (stopping as soon as a response is
received):
Time Search Request Sent To:
+0 Host A try 1
+1 (0+3/2) Host B try 1
+2 (1+3/2) Host A try 2
+5 (2+6/2) Host B try 2
+8 (5+6/2) Host A try 3
+14 (8+12/2) Host B try 3
+20 (14+12/2) Host A try 4
+32 (20+24/2) Host B try 4
+44 (20+24/2) (give up - no response)
ERRORScldap_search_s() returns LDAP_SUCCESS if a search was successful and
the appropriate LDAP error code otherwise. See ldap_error(3LDAP) for
more information.
ATTRIBUTES
See attributes(5) for a description of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
│Interface Stability │ Evolving │
└────────────────────┴─────────────────┘
SEE ALSOldap(3LDAP), ldap_error(3LDAP), ldap_search_s(3LDAP),
cldap_open(3LDAP), cldap_setretryinfo(3LDAP), cldap_close(3LDAP),
attributes(5), udp(7P)
Jan 27, 2002 CLDAP_SEARCH_S(3LDAP)