Subject: Re: SLPAttrCallback()

From: James Kempf <[email-masked]>
Date: Thu, 22 Jun 2000 14:26:42 -0700 (PDT)

>How often can SLPAttrCallback() expect to be called? If I call
>SLPFindAttrs() with a URL, am I guarenteed that the callback will be
>called at most once? 
>
The callbacks are always called at least one, even if nothing
is available, because they need to get the SLP_LAST_CALL status code.
This ensures that the callback can release any locks necessary to
restart any threads that may be waiting for results.

>If I call SLPFindAttrs() with a type, how do I know which service is
>associated with each set of attributes?

You don't, but that is a feature of the protocol, not the API. Basically,
AttrRqst by service type retrieves all attributes for all services
of the given type. Based on the result, a client can formulate
a SrvRqst, since it will then know what attribute tags and values
are being advertised.

Incidently, removal of AttrRqst by service type is on the list of
simplifications that Erik and I are proposing, going to proposed
standard. It is somewhat complicated to implement, and rarely used.

		jak

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From: Evan Hughes <[email-masked]>
Date: Fri, 23 Jun 2000 09:35:14 -0400 (EDT)

> restart any threads that may be waiting for results.

 Sorry, I didn't word that one well. What I meant to say is: Is the
application programmar guarenteed that there will be zero or one calls to
the callback (excluding the LAST_CALL)? ie, can the attributes for a
single host be broken across multiple calls to the callback?

e