Inotify_cpp

A set of C++ classes encapsulating the functionality of the C-language inotify library

Inotify_cpp creates an event-driven interface to the Linux inotify API, allowing a developer to hook into filesystem events without the hassle of implementing a read-handle loop or directly manipulating file descriptors.

Instead, monitoring a filesystem is as easy as writing an event handler and attaching it to a watch.

Current features:

Inotify_cpp currently implements all functionality provided by the standard C API with the following exceptions:

• Cookie handling for move/rename events is not yet present
• Watches cannot yet be removed or modified

The primary advantage of of Inotify_cpp over the standard inotify API is its event-driven interface.

Planned features:

Inotify_cpp will provide all the functionality of inotify, with several additions:

• Simple event checking without manipulating flags
• Abstraction of the IN_MOVED_FROM/IN_MOVED_TO events' cookie
• Inherent support for recursive watches
• Warning events when approaching limit for number of watches

Usage:

This repository contains both the Inotify_cpp library and an example application. For ease of reference, this is the implementation of the example application:

#include <iostream>
#include <thread>
#include "InotifyManager.h"
using namespace std;

class MyEventHandler : public InotifyEventHandler {
private:
	int eventCount = 0;
public:
	bool handle(InotifyEvent &e){
		string t;
		
		if(e.getFlags() & IN_CREATE)
			t = string("creation");
		else if(e.getFlags() & IN_DELETE)
			t = string("deletion");
		else
			t = string("unknown");
			
		cout << "An event occurred!" << endl;
		cout << " * Name : " << e.getName() << endl;
		cout << " * Type : " << t << endl;
		cout << endl;
	
		if(++eventCount == 5)
			return true;
		return false;
	}
};

int main(int argc, char *argv[]){

	if(argc != 2){
		cerr << "Please specify a directory to watch." << endl;
		cerr << "usage: " << argv[0] << " <directory_path>" << endl;
		return 1;
	}

	InotifyManager m;
	MyEventHandler h;
	InotifyWatch  *w = m.addWatch(argv[1], IN_CREATE | IN_DELETE);

	w->addEventHandler(h);

	thread t = m.startWatching();
	t.join();

	return 0;
}

The application provided in this repository will soon be extended to provide a simple configurable interface to inotify, allowing arbitrary commands to be run when filesystem events occur.