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digitalmars.D - LibEvent, signals or communication between threads

reply "Shadow_exe" <shadow_exe ukr.net> writes:
Hello everyone.
Faced with an interesting challenge, and how to solve it and 
found no tracks.
The problem is the following:
I have 2 thread, which are created in the main flow, 
respectively, of each other, they do not know, but I want to 
create a dialogue between the thread. I want to first thread 
could tell the second thread to perform some function.
The queue is implemented through a library libevent.

Who faced a similar problem or just knows how to solve this issue 
- please help.
May 08 2012
next sibling parent reply Gor Gyolchanyan <gor.f.gyolchanyan gmail.com> writes:
Try looking at std.concurrency.
You'll find a message passing mechanism there.

On Tue, May 8, 2012 at 2:25 PM, Shadow_exe <shadow_exe ukr.net> wrote:

 Hello everyone.
 Faced with an interesting challenge, and how to solve it and found no
 tracks.
 The problem is the following:
 I have 2 thread, which are created in the main flow, respectively, of each
 other, they do not know, but I want to create a dialogue between the thread.
 I want to first thread could tell the second thread to perform some
 function.
 The queue is implemented through a library libevent.

 Who faced a similar problem or just knows how to solve this issue - please
 help.




-- 
Bye,
Gor Gyolchanyan.
May 08 2012
next sibling parent "Shadow_exe" <shadow_exe ukr.net> writes:
Yes, there is some communication between the thread, but it is 
locked and the thread waits for him not come something like a 
signal.
My task is not to block the trade and send a signal in this 
thread.

On Tuesday, 8 May 2012 at 14:29:37 UTC, Gor Gyolchanyan wrote:

 Try looking at std.concurrency.
 You'll find a message passing mechanism there.

 On Tue, May 8, 2012 at 2:25 PM, Shadow_exe <shadow_exe ukr.net> 
 wrote:

 Hello everyone.
 Faced with an interesting challenge, and how to solve it and 
 found no
 tracks.
 The problem is the following:
 I have 2 thread, which are created in the main flow, 
 respectively, of each
 other, they do not know, but I want to create a dialogue 
 between the thread.
 I want to first thread could tell the second thread to perform 
 some
 function.
 The queue is implemented through a library libevent.

 Who faced a similar problem or just knows how to solve this 
 issue - please
 help.
May 08 2012
prev sibling parent reply sclytrack <sclytrack iq87.fr> writes:
On 05/08/2012 04:29 PM, Gor Gyolchanyan wrote:

 Try looking at std.concurrency.
 You'll find a message passing mechanism there.

 On Tue, May 8, 2012 at 2:25 PM, Shadow_exe<shadow_exe ukr.net>  wrote:

 Hello everyone.
 Faced with an interesting challenge, and how to solve it and found no
 tracks.
 The problem is the following:
 I have 2 thread, which are created in the main flow, respectively, of each
 other, they do not know, but I want to create a dialogue between the thread.
 I want to first thread could tell the second thread to perform some
 function.
 The queue is implemented through a library libevent.

 Who faced a similar problem or just knows how to solve this issue - please
 help.




Andrei's "Concurrency in the D programming language". You can google it.

http://www.informit.com/articles/article.aspx?p=1609144&seqNum=7
May 08 2012
parent reply =?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:
On 05/08/2012 09:00 AM, sclytrack wrote:

 On 05/08/2012 04:29 PM, Gor Gyolchanyan wrote:

 Try looking at std.concurrency.
 You'll find a message passing mechanism there.

 On Tue, May 8, 2012 at 2:25 PM, Shadow_exe<shadow_exe ukr.net> wrote:

 Hello everyone.
 Faced with an interesting challenge, and how to solve it and found no
 tracks.
 The problem is the following:
 I have 2 thread, which are created in the main flow, respectively, of
 each
 other, they do not know, but I want to create a dialogue between the
 thread.
 I want to first thread could tell the second thread to perform some
 function.
 The queue is implemented through a library libevent.

 Who faced a similar problem or just knows how to solve this issue -
 please
 help.




 Andrei's "Concurrency in the D programming language". You can google it.

 http://www.informit.com/articles/article.aspx?p=1609144&seqNum=7


I have written a chapter about the same:

   http://ddili.org/ders/d.en/concurrency.html

Although not directly related, the "Thread names" title there has an 
example where two threads discover each other by their names.

Ali

-- 
D Programming Language Tutorial: http://ddili.org/ders/d.en/index.html
May 08 2012
parent reply "Shadow_exe" <shadow_exe ukr.net> writes:
Thank You! As would there sometimes You have helped.
But I'm afraid that these methods me not suitable because 
libevent already creates a queue and turn me not to come out to 
do.
Information how to send that is the signal to the next thread I 
have not found this information that have been granted to You - 
I've read.

Okay, I will do through юниксовые sockets.


On Tuesday, 8 May 2012 at 17:09:53 UTC, Ali Çehreli wrote:

 On 05/08/2012 09:00 AM, sclytrack wrote:

 On 05/08/2012 04:29 PM, Gor Gyolchanyan wrote:

 Try looking at std.concurrency.
 You'll find a message passing mechanism there.

 On Tue, May 8, 2012 at 2:25 PM, 
 Shadow_exe<shadow_exe ukr.net> wrote:

 Hello everyone.
 Faced with an interesting challenge, and how to solve it and 
 found no
 tracks.
 The problem is the following:
 I have 2 thread, which are created in the main flow, 
 respectively, of
 each
 other, they do not know, but I want to create a dialogue 
 between the
 thread.
 I want to first thread could tell the second thread to 
 perform some
 function.
 The queue is implemented through a library libevent.

 Who faced a similar problem or just knows how to solve this 
 issue -
 please
 help.




 Andrei's "Concurrency in the D programming language". You can 
 google it.

 http://www.informit.com/articles/article.aspx?p=1609144&seqNum=7


 I have written a chapter about the same:

   http://ddili.org/ders/d.en/concurrency.html

 Although not directly related, the "Thread names" title there 
 has an example where two threads discover each other by their 
 names.

 Ali
May 08 2012
parent Sean Kelly <sean invisibleduck.org> writes:
On May 8, 2012, at 11:13 AM, Shadow_exe wrote:


 Thank You! As would there sometimes You have helped.
 But I'm afraid that these methods me not suitable because libevent =


already creates a queue and turn me not to come out to do.

 Information how to send that is the signal to the next thread I have =


not found this information that have been granted to You - I've read.

=20
 Okay, I will do through =D1=8E=D0=BD=D0=B8=D0=BA=D1=81=D0=BE=D0=B2=D1=8B=


=D0=B5 sockets.

std.concurrency uses a condition variable internally to signal the =
waiting thread when new messages have arrived.  As this is an =
implementation detail, it isn't exposed to the user.

libevent is unfortunately somewhat limited in the events that can be =
monitored.  It's pretty much just read/write events on a file =
descriptor, so using a socket or pipe is about the only way to notify a =
thread blocked on a libevent queue.  libev is more flexible in the range =
of events it offers.  I believe there's even a user-triggered event, =
though I bet this still uses a pipe internally.  And you're still stuck =
with the problem of sending the message and then separately triggering =
the event.

Really, messaging doesn't seamlessly integrate with high-performance =
socket IO.  Once Phobos gets a better networking API I'd like to provide =
a shim to proxy data to/from a socket Erlang-style, but that approach is =
really only desirable for simple cases, and cases where performance =
isn't a significant concern (since it tends to involve a lot of memory =
churn).  Beyond that=E2=80=A6 maybe I can cook up some way to let the =
user plug a notification mechanism into the message queue, so when a =
message is received, if nothing is waiting on the condition variable the =
other notification mechanism is used instead.=
May 08 2012
prev sibling parent Sean Kelly <sean invisibleduck.org> writes:
On May 8, 2012, at 3:25 AM, "Shadow_exe" <shadow_exe ukr.net> wrote:


 Hello everyone.
 Faced with an interesting challenge, and how to solve it and found no trac=


ks.

 The problem is the following:
 I have 2 thread, which are created in the main flow, respectively, of each=


 other, they do not know, but I want to create a dialogue between the thread=
. I want to first thread could tell the second thread to perform some functi=
on.

 The queue is implemented through a library libevent.
=20
 Who faced a similar problem or just knows how to solve this issue - please=


 help.

If you're already using libevent you can either send the message via a socke=
t or send the message using std.concurrency and then signal the other thread=
 by writing to a socket it's reading. You can call receiveTimeout(0) to not b=
lock on receive.=20=
May 08 2012