You can share a socket between two (or more) processes in Linux and even Windows. Under Linux (Or POSIX type OS), using fork() will cause the forked child to have copies of all the parent’s file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening … Read more
Explanation: This problem occurs because Chrome allows up to 6 open connections by default. So if you’re streaming multiple media files simultaneously from 6 <video> or <audio> tags, the 7th connection (for example, an image) will just hang, until one of the sockets opens up. Usually, an open connection will close after 5 minutes of … Read more
What about SCTP. It’s a standard protocol by the IETF (RFC 4960) It has chunking capability which could help for speed. Update: a comparison between TCP and SCTP shows that the performances are comparable unless two interfaces can be used. Update: a nice introductory article.
The connection should remain open regardless but yes it’s often common to see protocols implement a heartbeat in order to help detect dead connections, IRC with the PING command for example.
For my suggestion, please read the last section: “When to use SO_LINGER with timeout 0”. Before we come to that a little lecture about: Normal TCP termination TIME_WAIT FIN, ACK and RST Normal TCP termination The normal TCP termination sequence looks like this (simplified): We have two peers: A and B A calls close() A … Read more
Yes, you can use the same port number for both TCP and UDP. Many protocols already do this, for example DNS works on udp/53 and tcp/53. Technically the port pools for each protocol are completely independent, but for higher level protocols that can use either TCP or UDP it’s convention that they default to the … Read more
HTTP is an application protocol. It basically means that HTTP itself can’t be used to transport information to/from a remote end point. Instead it relies on an underlying protocol which in HTTP’s case is TCP. You can read more about OSI layers if you are interested. Sockets on the other hand are an API that … Read more
Yes, local interprocess communication by unix domain sockets should be faster than communication by loopback localhost connections because you have less TCP overhead, see here.
A long time ago I read a great analogy for explaining the difference between the two. I don’t remember where I read it so unfortunately I can’t credit the author for the idea, but I’ve also added a lot of my own knowledge to the core analogy anyway. So here goes: A stream socket is … Read more
With socket.emit you can register custom event like that: server: var io = require(‘socket.io’).listen(80); io.sockets.on(‘connection’, function (socket) { socket.emit(‘news’, { hello: ‘world’ }); socket.on(‘my other event’, function (data) { console.log(data); }); }); client: var socket = io.connect(‘http://localhost’); socket.on(‘news’, function (data) { console.log(data); socket.emit(‘my other event’, { my: ‘data’ }); }); Socket.send does the same, but … Read more