Re: Reading From A Pipe

[José Alburquerque <jaalburquerque cox net>]

On Tue, 2010-05-11 at 16:19 -0400, José Alburquerque wrote:
> On Tue, 2010-05-11 at 19:37 +0000, pub wrote:
> > int    pipefd2[2];    /* Read pipe from child */
> > 
> > Glib::RefPtr<Glib::IOChannel> readChannel;
> > 
> > 
> > //Instantiate
> > Playback playback;
> > 
> > // Connect the signal handler
> > Glib::signal_io().connect(sigc::mem_fun(playback,
> > &Playback::readpipe), pipefd2[r], Glib::IO_IN);
> > 
> > // Create a writeChannel from the file descriptor
> > writeChannel = Glib::IOChannel::create_from_fd(pipefd1[w]);
> > 
> > // Create a readChannel from the file descriptor
> > readChannel = Glib::IOChannel::create_from_fd(pipefd2[r]);
> > 
> > app.run(playback);
> > 
> > 
> > // Read From Pipe
> > bool Playback::readpipe(Glib::IOCondition read_condition)
> > {
> >     static int linecount;    // Total lines expected
> >     static int count;    // Count of lines received
> > 
> > 
> > 
> >     if ((read_condition & Glib::IO_IN) == 0)
> >     {
> >         std::cerr << "Exxx: Invalid read response" << std::endl;
> >     }
> >     else
> >     {
> >         #ifdef GLIBMM_EXCEPTIONS_ENABLED
> >         readChannel->read_line(readbuffer);
> >         #else
> >         std::auto_ptr<Glib::Error> ex;
> >         readChannel->read_line(readbuffer, ex);
> >         if(ex.get())
> >             std::cerr << "Exxx: " << ex->what() << std::endl;
> >         #endif //GLIBMM_EXCEPTIONS_ENABLED
> > 
> >         /* Append message read from pipe to textbuffer */
> >         m_msg->insert(m_msg->end(), readbuffer);
> >     }
> >     return true;
> > } //End of readpipe()
> 
> My suggestion would be to try running the code through a debugger.  I
> find this a lot easier than guessing at what is happening (unless
> something is blatantly clear from a quick look at the code).  Perhaps
> others can more quickly see the problem than I can right now.

scratch "right now".

-- 
José