Best way to check if a file has changed?

clone45 · January 9, 2023, 2:33am

Hello!

I have some newer modules that utilize user-editable external text files. People have requested that these files be automatically loaded if they’ve been updated while a patch is running. I’m sure that someone’s solved this already, so I thought I’d ask the community – What’s a good approach to this?

Thanks!
Bret

Jens.Peter.Nielsen · January 9, 2023, 2:59am

VCV-Prototype used efsw

github.com

VCVRack/VCV-Prototype/blob/f693e763335b5912ddfc2f8e26f687ffcf3693e6/src/Prototype.cpp#L289


      
          
          
		if (path == "")
          			return;
          
          
		this->path = path;
          		loadPath();
          
          
		if (this->script == "")
          			return;
          
          
		// Watch file
          		std::string dir = system::getDirectory(path);
          		efsw = efsw_create(false);
          		efsw_addwatch(efsw, dir.c_str(), watchCallback, false, this);
          		efsw_watch(efsw);
          	}
          
          
	void loadPath() {
          		// Read file
          		std::ifstream file;
          		file.exceptions(std::ifstream::failbit | std::ifstream::badbit);

clone45 · January 9, 2023, 3:28am

Ah, thanks! I’ve never heard of that before. I’ll give it a shot.

clone45 · January 10, 2023, 1:46am

Does someone have a few minutes to help me understand something that I’ve never really worked with before? I’m hoping to use the efsw library, as @Jens.Peter.Nielsen suggested, but I don’t know how to add it to my project.

When I look at VCV-Prototype, there’s a item called “efsw” in the repository which, one clicked, opens up the efsw project in github. Is this a “submodule”? (And if so, what steps should I take to include it in my code?)

Thanks!