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JavaScript

Wait for a Socket to Become Readable

See more Socket/SSL/TLS Examples

Demonstrates Socket.SelectForReading, which waits for read-ready activity on the socket, or on any contained socket when the object is a socket set. It returns 1 if ready, 0 on timeout, or -1 on error.

Background. A timeoutMs of 0 performs a nonblocking poll. With a socket set, this monitors many connections at once for readability.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

var socket = new CkSocket();

//  Connect to the server using TLS.
var bTls = true;
var maxWaitMs = 5000;
success = socket.Connect("example.com",5000,bTls,maxWaitMs);
if (success == false) {
    console.log(socket.LastErrorText);
    return;
}

//  Wait up to 5 seconds for read-ready activity on the socket (or, for a socket set, on any contained
//  socket).  Returns 1 if ready, 0 on timeout, or -1 on error.
var ready = socket.SelectForReading(5000);
if (ready < 0) {
    console.log(socket.LastErrorText);
    return;
}

if (ready !== 1) {
    console.log("No data became available before the timeout.");
    return;
}

console.log("The socket has data ready to read.");