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Entry  21 Jan 2007, Denis Bilenko, Bug Report, buffer bugs 
    Reply  22 Jan 2007, Stefan Ritt, Bug Report, buffer bugs 
       Reply  23 Jan 2007, Denis Bilenko, Bug Report, buffer bugs 
          Reply  23 Jan 2007, Stefan Ritt, Bug Report, buffer bugs 
          Reply  24 Jan 2007, Stefan Ritt, Bug Report, buffer bugs 
Message ID: 326     Entry time: 22 Jan 2007     In reply to: 323     Reply to this: 327
Author: Stefan Ritt 
Topic: Bug Report 
Subject: buffer bugs 

Denis Bilenko wrote:
1. Blocking calls to midas api aren't usable when client is connected through mserver. This is true at least for bm_receive_event, but seems to be a more general problem - midas application has call cm_yield within 10 seconds (or whatever timeout is set) to remain alive.
That not the case when RPC is not used.

The 10 seconds timeout you see comes from the RPC layer. If you call bm_receive_event and it blocks, then the client will consider a RPC timeout after 10 seconds. Has nothing to do with cm_yield(). Calling a blocking function via a sever connection is not a good idea anyhow, since this process then cannot respond on anything else, like run transitions. That's why I never used it and that's why I have not realized that behaviour. I did change it however such that bm_receive_event, if called without the ASYNC flag, disables the RPC timeout for this call and restores it afterwards. This is now in midas.c revision 3502. You can try this with midas/examples/lowlevel/produce and consume easily.

Denis Bilenko wrote:
2. On Windows, two processes on the same machine can send/receive events to each other only if they both use midas locally (through shared mem) or they both use midas via RPC (through mserver), but not if they use different ways.

I just tried again and it did work. I used produce/consume. If you enter just <return> for the host name, these programs connect locally. So I tried both producer locally, consumer remote, and vice versa, and both worked. I did however use consume with the callback functionality. I did not try your Python programs however. If you find out that produce/consume does work and your Python program don't, then adapt your Python programs to resemble produce/consume.

Denis Bilenko wrote:
3. Receiving/sending same events from the same process - was possible in 1.9.5-1, not so in the current version (revision 3501, mxml revision 45). Is this an intended behavior fix?

Yes. It was introduced in revision 3186 on July 28th, 2006. It fixed a problem that the buffer level was always shown as 100% full, even if there were no other clients registered. By ignoring the own process, the buffer level now correctly shows the "contents" of a buffer from 0..100%. It also gave a small speed improvement. If you want to send events to the own process, you have to do it from the calling level. Like if you call bm_send_event(), you call manually process_event or however your event receiving routine is called. This is also much faster than going through the buffer.
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