LassoLogout *logout;
char *session_dump; // must contain the session dump
                    // for the current user
int rc; // hold return codes
char *soap_response;

LassoHttpMethod method; // method to use, LASSO_HTTP_METHOD_REDIRECT, 
                        // LASSO_HTTP_METHOD_POST or LASSO_HTTP_METHOD_SOAP,
                        // other methods are rarely supported

logout = lasso_logout_new(server);
lasso_profile_set_session_from_dump(&logout->parent, session_dump);
// the second argument can be NULL, lasso_logout_init_request() will automatically choose the
// identity provider from the first assertion int the session
rc = lasso_logout_init_request(logout, "http://identity-provider-id/",
                method);
if (rc != 0) {
  ... // handle errors, most of them are related to bad initialization
      // or unsupported binding
}
rc = lasso_logout_build_request_msg(logout);
if (rc != 0) {
  ... // handle errors, most of them are related to bad initialization
      // or impossibility to build the query string (missing private keys for signing)
}

// now send the request
switch (method) {
    case LASSO_HTTP_METHOD_REDIRECT:
        // LASSO_PROFILE(logout)->msg_url contains the URL where the 
        // User Agent must be redirected
        ...
        // save the session and logout object, and store them attached to the RequestID of the
        // request, you will need them for handling the response
        session_dump = lasso_node_dump((LassoNode*)logout->parent.session);
        logout_dump = lasso_node_dump((LassoNode*)logout);
        break;
    case LASSO_HTTP_METHOD_POST:
        // you must build a form with a field name SAMLRequest (SAML 2.0) or LAREQ (ID-FF 1.2)
        // with the content of LASSO_PROFILE(logout)->msg_body
        // posting to the address LASSO_PROFILE(logout)->msg_url
        ...
        // save the session and logout object, and store them attached to the RequestID of the
        // request, you will need them for handling the response
        session_dump = lasso_node_dump((LassoNode*)logout->parent.session);
        logout_dump = lasso_node_dump((LassoNode*)logout);
        break;
    case LASSO_HTTP_SOAP:
        // makes a SOAP call, soap_call is NOT a Lasso function
        soap_response = soap_call(login->parent.msg_url, login->parent.msg_body);
        rc = lasso_logout_process_response_msg(logout, soap_response);
        if (rc != 0) {
            // handle errors, important ones are LASSO_LOGOUT_ERROR_UNSUPPORTED_PROFILE meaning
            // that one other service provider of the current session cannot be contacted by the
            // identity provider with the current binding, for example it only accept REDIRECT
            (asynchronous-binding) or
            // POST an we are using SOAP (synchronous-binding).
            ...
        }
        // everything is ok save the session
        session_dump = lasso_node_dump(logout->parent.session);
        // nothing to save because you killed the local session already
        break;
    default:
        // other binding neither are frequent or largely supported
        // so report an error
        break;
    }

LassoLogout *logout;
char *request_method = getenv("REQUEST_METHOD");

logout = lasso_logout_new(server);

if (strcmp(request_method, "GET") == 0) {
    char query_string = getenv("QUERY_STRING");
    rc = lasso_logout_process_response_msg(logout, query_string);
} elif (strcmp(request_method, "POST") == 0) {
    char *message;
    // message should contain the content of LARES or SAMLResponse fied, depending if this is an
    // ID-FF 1.2 or SAML 2.0 service.
    rc = lasso_logout_process_response_msg(logout, message);
}
if (rc != 0) {
    // handle errors, as we are already unlogged, those must go to a log file or audit trail,
    // because at this time the user do not care anymore. A report about a failure to logout to
    // the IdP can be eventually shown.
    ...
}

LassoLogout *logout;
char *session_dump;
char *request_method = getenv("REQUEST_METHOD");
int rc;
int method;

logout = lasso_logout_new(server);
// server must be previously initialized, it can be kept around
// and used for many transaction, it is never modified by any profile
if (strcmp(request_method. "GET") == 0) {
    method = LASSO_HTTP_METHOD_REDIRECT;
    char query_string = getenv("QUERY_STRING");
    rc = lasso_logout_process_request_msg(logout, query_string);
    if (rc != 0) {
        // handle errors
        ...
    }
} else if (strcmp(request_method, "POST") == 0) {
    char *message;
    // read submitted content if this is a form, put LAREQ or SAMLRequest field into message and
    set method to LASSO_HTTP_METHOD_POST
    // if content type is application/xml then put the full body of the POST inside message and
    // set method to LASSO_HTTP_METHOD_SOAP
    rc = lasso_logout_process_request_msg(logout, message);
    if (rc != 0) {
        // handle errors
        ...
    }
}
protocolProfile = lasso_provider_get_protocol_conformance(LASSO_PROVIDER(server));
if (protocolProfile == LASSO_LIBERTY_1_2) {
    char *session_index;
    LassoSamlNameIdentifier *name_id;
    LibLogoutRequest *logout_request;

    logout_request = LIB_LOGOUT_REQUEST(LASSO_PROFILE(logout)->request);
    session_index = logout_request->SessionIndex;
    name_id = logout_request->NameIdentifier;
    // lookup the session dump using session_index and name_id
} else if (protocolProfile == LASSO_SAML_2_0) {
    char *session_index;
    LassoSaml2NameID *name_id;
    LassoSamlp2LogoutRequest *logout_request;

    logout_request = LASSO_SAMLP2_LOGOUT_REQUEST(LASSO_PROFILE(logout)->request);
    session_index = logout_request->SessionIndex;
    name_id = logout_request->NameID;
    // lookup the session dump using session_index and name_id
}
lasso_profile_set_session_from_dump(LASSO_PROFILE(logout), session_dump);
// you can check other property of the request here if you want
// 
if (request is accepted) {
    rc = lasso_logout_validate_request(logout);
    if (rc != 0) {
        // handle errors..
        ...
    } else {
    .... // kill the local session
         // if local server is an identity provider, then traverse the session using
         // lasso_logout_get_next_providerID() and send logout request to all logged 
         // service providers.
    }
}
// if lasso_logout_validate_request() was not called this will automatically create a Failure
// response.
rc = lasso_logout_build_response_msg(logout);
if (rc != 0) {
    // handle errors..
    ...
}
// the response is produced with the same binding as the request
// see the previous request example for how to send the response
// the only change is for SOAP, you just need to print the msg_body as page content with a
// Content-type of application/xml.