polling

This question already has answers here : In Java, what is the best/safest pattern for monitoring a file being appended to? (7 answers) There are many approaches, one could use create a Program and just call the Unix tail command, however the problem with this is that the process must be installed on a Unix machine with tail installed. The other option is to just read the file, line by line until there are no more lines, sleep for a period of time and then try to read the next line and repeat. The question is what/how do I go about polling a file which is actively being written to. AFAIK there

I'm building a 2 Player game on Android. The game works turnwise, so player 1 waits until player 2 made his input and vice versa. I have a webserver where I run an API with the Slim Framework. On the clients I use Retrofit. So on the clients I would like to poll my webserver (I know it's not the best approach) every X seconds to check whether there was an input from player 2 or not, if yes change UI (the gameboard). Dealing with Retrofit I came across RxJava. My problem is to figure out whether I need to use RxJava or not? If yes, are there any really simple examples for polling with retrofit?

I'm needing to build in some pretty agressive "auto refresh" capabilities into a web application. It's kind of a photo gallery and the images are stored on AmazonS3 but the data about the images are stored in our own database. I've played around with polling the server and sending ajax calls to get the updated data. I'm really concerned about the load on the server(s) with this method. At times, the page would need to be updated every 15 to 30 seconds. I've been reading on Comet and I'm just not sold that this "hack" is a great idea. WebSockets would probably help but I'm concerned they are

I need to find a way to update a web App implemented with backbone . The use case will be the following: I have several Views, and each View, or maybe model/collection related to this view, needs to make different polling request to the server at different time for discovering some change. I am wondering what is the most general way to: 1) implement the Traditional Polling Request 2) implement the Long Polling Request 3) implement the HTML5 web socket P.S.: 1) The server is written in PHP. 2) For now I am looking for a solution without using HTML5 WebSockets because maybe with PHP is not so

I wrote a small TCP servers with socket() + POLLIN poll() + recv() + send() , but I don't know when to use POLLOUT poll or select writefds to poll on writable event. Can anyone give me an example of the real usage of POLLOUT ? The usual pattern is to use non-blocking file descriptors with poll() like this: When getting ready to poll() , Always set POLLIN because you are always interested in reading what the other end of the socket has send you. Except if you have a large backlog of incoming data and you intentionally want to make the other end wait before sending more. Set POLLOUT only if you

I have a Ruby script which is constantly updating a MySQL database. I want to show the " mysql_num_rows() " in realtime. So as an entry is entered into the database by the Ruby script I want the PHP script to update its mysql_num_row() count in realtime. I tried using <meta http-equiv="refresh" content="5"> , but I don't think this is the best solution. Does any one have a better solution? Use JavaScript on the page to periodically make a call to the server and get some data. Using the jQuery library for cross-browser support of AJAX, you would simply do this: jQuery(function($){ setInterval

If there is a REST resource that I want to monitor for changes or modifications from other clients, what is the best (and most RESTful) way of doing so? One idea I've had for doing so is by providing specific resources that will keep the connection open rather than returning immediately if the resource does not (yet) exist. For example, given the resource: /game/17/playerToMove a "GET" on this resource might tell me that it's my opponent's turn to move. Rather than continually polling this resource to find out when it's my turn to move, I might note the move number (say 5) and attempt to