Re: [win32] Glib::IOChannel error?

[Armin Burgmeier <armin arbur net>]

On Fri, 2008-11-14 at 18:11 +0100, Köntös Eszter wrote:
> Hi all,
> 
> I'm writing a crossplatform program that executes another application
> and reads from it's output. I'm using Glib::spawn_async_with_pipes to
> solve the process handling and i handle the pipes with Glib::IOChannel.
> The problem is that, if the application writes a string to it's output
> that contains central-european characters (like: á, é, ü, ő, etc.) than
> Glib::IOChannel::read_line throws the following exception:

Glib::IOChannel does implicit charset conversion, though I'm not exactly
sure from what to what. But if you know the program you are spawning
uses some specific character set (such as ISO-8859-2 (Central European))
for output, and expect to receive it as such in your application, then
you can try to disable that automatic charset conversion via
some_io_channel->set_encoding("");

> glibmm-CRITICAL ** :
> unhandled exception (type: Glib::Error) in signal handler:
> domain: g_convert_error
> code: 1
> what: invalid byte sequence in conversion input   /the message is
> localized so i tried to translate it to english, hope it's fits to the
> original message/
> 
> I have to use central-european charset, but i don't have any idea, how
> to solve this problem. Furthermore i can't catch any exceptions
> /Glib::IOChannelError or Glib::ConvertError, nor Glib::Error/, except (...).

If you are using the official gtkmm installer, then this might be
because of ABI incomptabilities between your Compiler (gcc 4.2.1) and
the one the official binaries were built with (gcc 3.4.5). You'll also
have trouble catching other exceptions thrown by glibmm or gtkmm then.

> This exception thrown only on windows; on linux everything works
> perfectly. I'm using MinGW compiler (gcc-4.2.1-sjlj-2,
> mingw32-make-3.81, mingwrt-3.15, w32api-3.12, binutils-2.18.50),
> gtk-2.14.4-1, gtkmm-2.14.1-3 and windows-1250 charset.
> 
> The code:
> void ProcessHandler::spawn(const Glib::ArrayHandle<std::string>& argv)
> {
>   try {
>     Glib::spawn_async_with_pipes(Glib::get_current_dir(),
>                                  argv,
> Glib::SpawnFlags(0)|Glib::SPAWN_SEARCH_PATH,
>                                  sigc::slot<void>(),
>                                  &child_,&stdin_,&stdout_,&stderr_);
>   } catch (Glib::SpawnError& ex) {...}
>   } catch (Glib::Error& ex) {...}
>   ...
> #ifdef WIN32 
>   ioch_in_=Glib::IOChannel::create_from_win32_fd(stdin_);
>   ioch_out_=Glib::IOChannel::create_from_win32_fd(stdout_);
>   ioch_err_=Glib::IOChannel::create_from_win32_fd(stderr_);
> #else
>   ioch_in_=Glib::IOChannel::create_from_fd(stdin_);
>   ioch_out_=Glib::IOChannel::create_from_fd(stdout_);
>   ioch_err_=Glib::IOChannel::create_from_fd(stderr_);
> #endif
> }
> 
> Glib::IOStatus ProcessHandler::read_line_from_out(Glib::ustring& str)
> {
>     try {
>         return ioch_out_->read_line(str);
>     } catch (Glib::IOChannelError& ex)  {...}
>     } catch (Glib::ConvertError& ex)  {...}
>     } catch (Glib::Error& ex)  {...}
>     } catch (...) {...}

Armin