Sth about open-ldap client api memory leak.

[Yuqing Tang <tang_yq@vinside.com>]

The code below will cause about 300k meory leak when I run it 1000 times. 
(I use oplenldap-stable-1.2.11) Why?

CODE:
if (( ld=ldap_init(_host,_port) ) == NULL)
{
    cout<<"ldap init err: "<<errno<<endl;
}

if (ldap_simple_bind_s(ld,_usr,_usrpwd)!=LDAP_SUCCESS)
{
    cout<<"ldap bind error:"<<ldap_err2string(ld->ld_errno)<<endl;
    ldap_unbind(ld);
    ld = NULL;
    exit(1);
}
int rc=ldap_search_s(ld,
                base,
                scope,
                filter,
                a,
                attronly,
                &res);
if (rc != LDAP_SUCCESS)
{
    cout<<"ldap search base:"<<base<<" filter:"<<filter
        <<" error:"<<ldap_err2string(ld->ld_errno)<<endl;
    if (ld) ldap_unbind(ld);
    exit(1);
}

if(!res)
{
    ldap_msgfree(res);
    res = NULL;
}

if (ld) ldap_unbind(ld);