timeout on utl_http

Hello,

I'm using Oracle 12.1.2.0.1 database and utl_http package. I created function to get response from service. I used set_transfer_timeout(10), assuming that function will exit if it lasted longer than 10 seconds. But, it seems this doesn't work like that. How can I call get_response and set maximal time for response to 10 seconds?

Here is the function:

create or replace function f_my_function

  (vc_url in varchar2, vc_xml in varchar2) return clob as

  l_envelope VARCHAR2(32767);

  l_result         VARCHAR2(32767) := null;

  l_http_request   UTL_HTTP.req;

  l_http_response  UTL_HTTP.resp;

  l_counter        PLS_INTEGER;