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<== Date ==> <== Thread ==>

Subject: Re: Channel Access monitoring tools
From: Bill Lavender <lavender@agni.phys.iit.edu>
To: benjamin.franksen@helmholtz-berlin.de, tech-talk@aps.anl.gov
Date: Mon, 14 May 2012 17:48:12 -0500
> > At present, I am doing something like this:
> > 
> > 1.  Invoke ca_create_channel() with a connection state change handler.
> >     The connection state change handler sets a flag to indicate that
> >     the connection has complete.
> > 
> > 2.  Call ca_pend_io() to make sure the request is sent on its way.
> 
> You want to use ca_flush (or was it called ca_flush_io?) for that. AFAIK 
> ca_pend_io does not send accumulated requests, it just waits for responses 
> (and other events).
> 
> Cheers
> Ben

I'm not sure about that.  The first sentence of the description for
ca_pend_io() says:

  Flushes the send buffer and then waits until outstanding queries complete
  or the specified time out expires.

When I look at the source code for EPICS Base 3.14.12.2, I see that
ca_pend_io() gets a ca_client_context object in the variable "pcac" and
then calls the pcac->pendIO() method of that object.  The pendIO()
method, in turn calls the this->flush() method of the same object.
ca_flush_io() instead directly calls pcac->flush() on the context
object.  So it looks like ca_pend_io() does everything that
ca_flush_io() does and more.

Bill Lavender


Replies:
Re: Channel Access monitoring tools Benjamin Franksen
References:
Channel Access monitoring tools Bill Lavender
Re: Channel Access monitoring tools Benjamin Franksen

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