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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: 323     Entry time: 21 Jan 2007     Reply to this: 326
Author: Denis Bilenko 
Topic: Bug Report 
Subject: buffer bugs 
Hello,

We've been using midas and have stumbled upon some inconsistent behaviour:
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.

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.

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?
To explain how to reproduce bugs, I will use 2 helper programs evprint.py and
evsend.py - for receiving and sending events respectively. You don't need
them, just something to send and receive events. (These are part of pymidas, which will be
released to public any time soon, but is quite usable already).

They both accept
* --path option in "host/experiment" format (for cm_connect_experiment call)
* --log option which command them to trace all midas' calls to terminal

evprint.py have two ways of receiving events
1) via looping over bm_receive_event
2) via providing callback to bm_request_event and looping over cm_yield(400) call

Example of use:
first-console$ python evprint.py receive
second-console$ python evsend.py 123
[first console]
id=2007 mask=2007 serial=2007 time=1169372833 len=3 '123'
So,

1. Blocking calls to midas api aren't usable when client is connected through
mserver.
$ python evprint.py --log --path 127.0.0.1/online receive"
cm_connect_experiment('127.0.0.1', 'online', 'evprint.py', None)
bm_open_buffer('SYSTEM', 1048576, &c_long(2)) -> BM_CREATED
bm_request_event(2, -1, -1, 2, &c_long(0), None)
... wait for a couple of seconds ...
[midas.c:9348:rpc_call] rpc timeout, routine = "bm_receive_event"
[system.c:3570:send_tcp] send(socket=0,size=8) returned -1, errno: 88 (Socket 
operation on non-socket)
[midas.c:9326:rpc_call] send_tcp() failed

bm_receive_event(2, ...) -> RPC_TIMEOUT

bm_remove_event_request(2, 0) -> BM_INVALID_HANDLE
bm_close_buffer(2) -> BM_INVALID_HANDLE
cm_disconnect_experiment()

2. Missing events on windows
a) Both use midas locally - works
   1: python evprint.py receive
   2: python evsend.py 123
   1: id=2007 mask=2007 serial=2007 time=1169372833 len=3 '123'
b) Both use midas via RPC - works
   1: python evprint.py --path 127.0.0.1/ dispatch
   2: python evsend.py --path 127.0.0.1/ 123
   1: id=2007 mask=2007 serial=2007 time=1169373366 len=3 '123'
c) Receiver uses midas locally, sender uses mserver - doesn't work on windows
   1: python evprint.py dispatch
   2: python evsend.py --path 127.0.0.1/ 123
   1: (nothing printed)
d) The other way around - doesn't work on windows
   1: python evprint.py --path 127.0.0.1/ dispatch
   2: python evsend.py 123
   1: (nothing printed)
No such problem on linux.

3. Receiving/sending same events from the same process.
To reproduce this, just request events, send one and then try to receive
it via cm_yield. I care for this, because I have a test in pymidas which
relies on this behavior.

hope this will help.
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