Quick Start (C++)¶

Project Setup¶

This example project setup uses CMake to build your project. In order to use system dependencies you must first install linq-network and it’s dependencies into your system. For example on how to compile and install linq-network and it’s dependencies, see Library Configuration Options

CMakeLists.txt with system depenencies¶

CMakeLists.txt

add_executable(server main.cpp)
target_link_libraries(server linq-netw)
install(TARGETS server DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)

Build application

mkdir build
cd build
cmake -DLINQ_USE_SYSTEM_DEPENDENCIES:BOOL=ON ..
make
make install

CMakeLists.txt for reproducible builds¶

Download dependencies

git submodule add https://bitbucket.org/Altronix/linq-network external/linq-network
git submodule add https://github.com/zeromq/libzmq external/libzmq
git submodule add https://github.com/zeromq/czmq external/czmq

CMakeLists.txt

add_subdirectory(external/linq-network)
add_subdirectory(external/libzmq)
add_subdirectory(external/czmq)
add_executable(server main.cpp)
target_link_libraries(server linq-netw)
install(TARGETS server DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)

Build application

mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=./install ..
make
make install

Process Network Events (Optional)¶

The LinQ Network C++ binding uses a lambda style API to listen for incoming network events.

Alert¶

The “Alert Callback” is called from the LinQ Network library when a LinQ Enabled device generates an alert. An optional application context, alert struct, and a email struct are passed into your application alert callback function.

std::function<void(linq_network_alert_s*, linq_network_email_s*, Device&)>;

See Also

Heartbeat¶

The “Heartbeat Callback” is called from the LinQ Network library when a LinQ Enabled device sends a heartbeat. An optional application context, and the device serial number are passed into your application heartbeat callback function.

std::function<void(const char*, Device&)>;

Error¶

The “Error Callback” is called from the LinQ Network library when the LinQ Network library detects a runtime error. An optional application context, and an linq_network_error are passed into your application error callback function.

std::function<void(E_LINQ_ERROR, const char*, const char*)> error_;

See Also

linq_network_error

Ctrlc¶

The “Ctrlc Callback” is called from the LinQ Network library when the LinQ Network library is about to shutdown. An optional application context is passed into your application ctrlc callback function.

std::function<void()> ctrlc_;

Process Network IO¶

The LinQ Network library performs non-blocking IO inside of your thread. To process LinQ Network IO you must call the linq_network_poll routine from inside of your main loop. linq_network_poll() will call any callbacks you have provided from the same thread context as your main application.

int
main(int argc, char* argv[])
{
   // Initialize your app
   altronix::linq linq{};

   while(sys_running())
   {
     linq.poll(5);
   }

   // ...
}

Note

For multi threaded support, use one of the higher level language bindings that provide thread safe wrappers, or create your own IPC scheme per your applications needs.

See Also

linq_network_poll
sys_running

Complete Application¶

#include "altronix/linq_network.hpp"

int
main(int argc, char *argv[])
{
  altronix::Linq netw{};

  netw.on_error([this](E_LINQ_ERROR error, const char *serial, const char *err) {
      // Received an error
    }).on_heartbeat([this](const char *serial, Device& device) {
      // Received a heartbeat
    }).on_alert([this](linq_alert_s* alert, linq_email_s* email, Device& device) {
      // Received an alert
    });

  while (true)
  {
    netw.poll(5);
  }
}