file_monitor

Lean library to observe file changes in a specific directory path. Primarily meant for asset hotloading in games and 3D engines. It does not aim to report a complete list of changes; instead, the results should be treated as hints which can be used to trigger asset reloading.

Install via conan

First you are going to have to add both the bincrafters and my repository:

conan remote add bincrafters https://api.bintray.com/conan/bincrafters/public-conan
conan remote add ltjax https://api.bintray.com/conan/ltjax/conan 

Then you can add the dependency like this:

file_monitor/1.0@ltjax/testing

Usage

You can instantiate a file monitor by calling the factory function file_monitor::make_monitor(...) with a path:

#include <file_monitor/factory.hpp>

int main(int argc, char** argv)
{
  auto monitor = file_monitor::make_monitor("some_folder");
  /* ... */
}

To monitor file changes, you need to periodically call poll(), e.g. in your main loop:

while (keep_running)
{
  updateYourProgram();
  monitor->poll([](auto const& files)
  {
    // files is a std::vector of files that have changed
  });
}

Note that the monitor will only detect changes on files that existed when it was started. File renaming and creation is not detected.

Platform support

The file monitor works on Windows, Linux and Mac OS X. It can be built with VC++ 2017, and recent g++ and clang versions. It requires C++14, but C++17 is recommended.

Dependencies

file_monitor does not need any dependencies from C++17 on. For older standards, Boost.Filesystem is required.

Integration

There are two ways to integrate file_monitor with your application. Either drop it into your source folder and use CMake's add_subdirectory() or use the install target to install the library in your environment.