OpenLDAPConnection::bindAsUser both binds to the target LDAP server and invokes ldap_set_rebind_proc, to register a callback which actually performs the binding operation. This callback will get executed if a subsequent query operation chases a referral to a delegated LDAP server, and finds that we need to bind to the new server using our original bind parameters. The callback is provided with the address of additional arguments which contain the bind parameters. This address must be valid when the callback is called.

Because the callback can be invoked during any call to several OpenLDAPConenction methods, the pointer registered in ldap_set_rebind_proc must be to a value whose lifetime is guaranteed to live at least as long as the OpenLDAPConnection itself.