gtalk(XMPP) initial response not always contain a <stream:features>

Question

i send to talk.google.com with a initial stanza like:

<?xml version='1.0'?>
<stream:stream
from='[email protected]'
to='gmail.com'
version='1.0'
xml:lang='en'
xmlns='jabber:client'
xmlns:stream='http://etherx.jabber.org/streams'>

and as the rfc6120 said, server should response with a stanza that has tag named "stream:features"

but I've tried a lot of time but the response rarely contained the "stream:features" so I have to make a circulation waiting for a response which contains a "stream:features".

Answer 1

You should get a stream:stream open tag before the stream:features:

<stream:stream xmlns:stream="http://etherx.jabber.org/streams" 
               xmlns="jabber:client" 
               from="gmail.com" 
               id="407014FD9646082B" 
               version="1.0">
  <stream:features>
    <starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls">
      <required/>
    </starttls>
    <mechanisms xmlns="urn:ietf:params:xml:ns:xmpp-sasl">
      <mechanism>X-GOOGLE-TOKEN</mechanism>
      <mechanism>X-OAUTH2</mechanism>
    </mechanisms>
  </stream:features>

I'd urge you to use one of the existing client libraries linked to at xmpp.org. You're likely to have a bunch of other problems before you've got something running well if you're doing synchronous reads.