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/* Copyright (C) 2004 The glibmm Development Team
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <fcntl.h>
#include <glibmm.h>
#include <iostream>
#include <limits.h>
#include <string>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "fdstream.h"
fdstream input_stream;
Glib::RefPtr<Glib::MainLoop> mainloop;
/*
send to the fifo with:
echo "Hello" > testfifo
quit the program with:
echo "Q" > testfifo
*/
// this will be our signal handler for read operations
// it will print out the message sent to the fifo
// and quit the program if the message was, or began
// with, 'Q'
bool
MyCallback(Glib::IOCondition io_condition)
{
if ((io_condition & Glib::IO_IN) == 0)
{
std::cerr << "Invalid fifo response" << std::endl;
}
else
{
// stream for stdout (does the same as std::cout
// - this is an example of using fdstream for output)
fdstream out(1, false);
std::string text;
input_stream >> text;
out << text << std::endl;
if (text[0] == 'Q')
mainloop->quit();
}
return true;
}
int main(/* int argc, char *argv[] */)
{
Glib::init();
// the usual Glib::Main object
mainloop = Glib::MainLoop::create();
if (access("testfifo", F_OK) == -1)
{
// fifo doesn't exit - create it
if (mkfifo("testfifo", 0666) != 0)
{
std::cerr << "error creating fifo" << std::endl;
return -1;
}
}
const auto read_fd = open("testfifo", O_RDONLY);
if (read_fd == -1)
{
std::cerr << "error opening fifo" << std::endl;
return -1;
}
input_stream.attach(read_fd);
input_stream.connect(sigc::ptr_fun(MyCallback), Glib::IO_IN);
// and last but not least - run the application main loop
mainloop->run();
// now remove the temporary fifo
if (unlink("testfifo"))
std::cerr << "error removing fifo" << std::endl;
return 0;
}
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