From:
Jeff Squyres <jsquyres@cisco.com>
To:
Mudassar Majeed <mudassarm30@yahoo.com>
Cc: Open
MPI Users <users@open-mpi.org>
Sent:
Friday, July 15, 2011 3:30 AM
Subject:
Re: [OMPI users] Urgent Question regarding,
MPI_ANY_SOURCE.
Right. I thought you were asking about receiving *another*
message from whomever you just received from via ANY_SOURCE.
If you want to receive from a specific sender, you just
specify the rank you want to receive from -- not ANY_SOURCE.
You will always only receive messages that were sent to
*you*. There's no MPI_SEND_TO_ANYONE_WHO_IS_LISTENING
functionality, for example. So your last statement: "But
when it captures with .. MPI_ANY_SOURCE and MPI_ANY_TAG, the
receiver will capture any message (even not targetted for
it)" is incorrect.
I guess I still don't understand your question...?
On Jul 14, 2011, at 9:17 PM, Mudassar Majeed wrote:
>
> I know this, but when I compare status.MPI_SOURCE with
myid, they are different. I guess you need to reconsider my
question. The MPI_Recv function seems to capture message
from the queue with some search parameters like source, tag
etc. So in case the receiver does not know the sender and
wants to receive only that message which was sent for this
receiver. But when it captures with source as MPI_ANY_SOURCE
and MPI_ANY_TAG, the receiver will capture any message (even
not targetted for it).
>
> regards,
> Mudassar
>
>
> From: Jeff Squyres <
jsquyres@cisco.com>
> To: Mudassar Majeed <
mudassarm30@yahoo.com>;
Open MPI Users <
users@open-mpi.org>
> Sent: Friday, July 15, 2011 1:58 AM
> Subject: Re: [OMPI users] Urgent Question regarding,
MPI_ANY_SOURCE.
>
> When you use MPI_ANY_SOURCE in a receive, the rank of
the actual sender is passed back to you in the
status.MPI_SOURCE.
>
> On Jul 14, 2011, at 7:55 PM, Mudassar Majeed wrote:
>
> > Hello people,
> > I am trapped in the
following problem plz help me. Suppose a process A sends a
message to process B. The process B will receive the message
with MPI_Recv with MPI_ANY_SOURCE in the source argument.
Let say process B does not know that A is the sender. But I
want B to receive message from process A (the one who
actually sends the message to process B). But if I use
MPI_ANY_SOURCE, then any message from any source is captured
by process B (let say there are other processes sending
messages). Instead of MPI_ANY_SOURCE I cannot use A in the
source argument as B does not know about the sender. What
should I do in this situation ?
> >
> > regards,
> > Mudassar Majeed
> > _______________________________________________
> > users mailing list
> >
users@open-mpi.org
> >
http://www.open-mpi.org/mailman/listinfo.cgi/users
>
>
> --
> Jeff Squyres
>
jsquyres@cisco.com
> For corporate legal information go to:
>
http://www.cisco.com/web/about/doing_business/legal/cri/
>
>
>
--
Jeff Squyres
jsquyres@cisco.com
For corporate legal information go to:
http://www.cisco.com/web/about/doing_business/legal/cri/