But another problem is raised: when I receive 2 command one after other quickly, I miss the second, so...

Is there a method to launch a signal directly into another thread? Something like:

boost::thread(boost::bind(signal_OnData, ptrToObj))

I'm not sure I understand your issue, but anyway, in such kind of task you can consider using boost.asio. Using asio::io_service::post you can conveniently post functors between different threads, without the need for explicit locking.

You mean using asio::io_service::post instead of signals or using asio::serial_port instead of my serial classes?

No I just mean using asio::io_service as a functor queue processor, but if you use asio you definitely can benefit from its serial_port class as well.

If you have a minimal code snippet I will grateful!

If you want to see a working code with asio, you can refer to one the asio examples, but in general I mean the following scheme (pseudo-code!): // encapsulates yours or asio i/o object, like socket, serial_port etc. class connection : public boost::enable_shared_from_this<connection> { public: connection(boost::asio::io_service &io) : io_(io) {} public: void send(data_type data) { // since send() might be called from a client thread, do not process the data here, // just post it to the io_ thread(s), where the data will be delivered to the socket/port io_.post(&connection::do_send, shared_from_this(), data); } private: // this method is always called within io_ thread(s) void data_received() { //issue the signal } void do_send(data_type data) { // send the data } }; // listens to the connection; class data_receiver { void data_received(data_type data) { doSomething(); connection->send(somethingElse); } };

Igor R ha scritto:

// encapsulates yours or asio i/o object, like socket, serial_port etc. class connection : public boost::enable_shared_from_this<connection> { public: connection(boost::asio::io_service &io) : io_(io) {}

Hi Igor, is there a reason to create the io_service outside the class? Can I create an instance of it directly into the connection object?

public: void send(data_type data) { // since send() might be called from a client thread, do not process the data here, // just post it to the io_ thread(s), where the data will be delivered to the socket/port io_.post(&connection::do_send, shared_from_this(), data); } private: // this method is always called within io_ thread(s) void data_received() { //issue the signal } void do_send(data_type data) { // send the data } };

In your example you use io_.post() into the send method, why you don't use it also in the data_received? Thanks! Daniele.

Igor R ha scritto:

...

is there a reason to create the io_service outside the class? Can I create an instance of it directly into the connection object?

Yes, you can. But usually you don't want to create io_service for every connection or for every "active object" (you can use a single io_service for all these objects or use io_service-per-cpu strategy - see asio examples for details), that's why that you might want to manage io_service(s) creation outside these objects.

Ok, now I've understand! I'm sorry but it's my first approach to asio!

But if you use some other i/o object to communicate with socket/serial port, and utilize io_service just to process functors asyncronously, and you wish to notify connection user from io_service thread - then you can use the same technique there. It's just matter of your design. Anyway, I recommend you to look at the asio tutorial and examples, to find out some common usage scenarios and design proposals.

Yes, this is exactly what I have to do. I will looking into the tutorials!! Just one last thing.. I've tried to to something like this (where signal_OnData is a signal): void SerialPort::reading() { .... data available... //signal_OnData(); _io.post( boost::bind(&SerialPort::Post_OnData, this) ); } void SerialPort::Post_OnData() { signal_OnData(); }; but the SerialPort::Post_OnData is not called, is this my design wrong? Thanks very mutch for your support!!! Daniele.

Igor R ha scritto:

...

Just one last thing..

I've tried to to something like this (where signal_OnData is a signal):

void SerialPort::reading() { .... data available... //signal_OnData(); _io.post( boost::bind(&SerialPort::Post_OnData, this) ); }

void SerialPort::Post_OnData() { signal_OnData(); };

but the SerialPort::Post_OnData is not called, is this my design wrong?

I guess that your io_service is not running, so noone processes its queue. You have to call io_service::run function, it's kindof "message loop" of io_service: http://www.boost.org/doc/libs/1_38_0/doc/html/boost_asio/tutorial/tutdaytime...

Yes, I've called the _io.run() into my SerialPort constructor, but I think it end immediately because it has no work to do!! I'm reading docs and articles but one thing I can't understand... In my SerialPort class the reading method is called in a separate thread when I open the device and it doesn't return until I stop it: _thread.reset( new boost::thread( boost::bind(&SerialPort::reading, this)) ); using asio I think I have to 'bind' it to io_service::run so when I call _io.run() it call SerialPort::reading, but how?! Cheers, Daniele.