Brian F. Feldman wrote:
> On Tue, 6 Jul 1999, John Polstra wrote:
> 
>> In article <[EMAIL PROTECTED]>,
>> 
>> The application itself has to get involved if it wants to do async
>> name lookups, or async anything else, for that matter.  Suppose you
>> do have an async thread to do hostname lookups as you propose.  What
>> is the application going to do while that thread is waiting for the
>> lookup to complete?  It depends on the application, and thus it has
>> to be coded into the application.  Maybe there's nothing useful the
>> application could do until the lookup returns.
>> 
>> I've been told that it works fine to use libc_r and put the name
>> lookups into a separate thread.  But to take advantage of it, the
>> application has to have something useful it wants to do (and can do)
>> in the meantime.
> 
> It would let the other threads run more while the lookup is occurring.
> Wouldn't that be the most natural expectation of it? Or would this
> be too hard without kernel-assisted threading?

What I'm saying is, we already have that in multi-threaded
applications.  The system can't just provide it automatically to
single-threaded applications; they wouldn't know how to take advantage
of it.  In other words:

    * Multi-threaded applications already have it.
    * Single-threaded applications can't use it.

John
---
  John Polstra                                               [EMAIL PROTECTED]
  John D. Polstra & Co., Inc.                        Seattle, Washington USA
  "No matter how cynical I get, I just can't keep up."        -- Nora Ephron



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