What is the equivalent of Windows process.on ('SIGINT') in node.js?

Question

I follow the instructions here (listening for SIGINT events) to gracefully close my node.js application hosted on Windows 8 in response to Ctrl-C or shutting down the server.

But Windows does not have SIGINT . I also tried process.on('exit') , but this seems to be doing something productive lately.

On Windows, this code gives me: Error: no such module

 process.on( 'SIGINT', function() { console.log( "\ngracefully shutting down from SIGINT (Crtl-C)" ) // wish this worked on Windows process.exit( ) }) 

On Windows, this code runs, but it's too late to do something elegant :

 process.on( 'exit', function() { console.log( "never see this log message" ) }) 

Is there an equivalent SIGINT event on Windows?

Answer 1

You must use the readline module and listen for the SIGINT event:

http://nodejs.org/api/readline.html#readline_event_sigint

 if (process.platform === "win32") { var rl = require("readline").createInterface({ input: process.stdin, output: process.stdout }); rl.on("SIGINT", function () { process.emit("SIGINT"); }); } process.on("SIGINT", function () { //graceful shutdown process.exit(); }); 

Answer 2

If you do not need the readline import for other tasks, I would suggest importing readline after the program has verified that it works on Windows. In addition, for those who may not know, this works on both 32-bit and Windows 64-bit systems (which will return the keyword "win32"). Thanks for this Gabriel solution.

 if (process.platform === "win32") { require("readline") .createInterface({ input: process.stdin, output: process.stdout }) .on("SIGINT", function () { process.emit("SIGINT"); }); } process.on("SIGINT", function () { // graceful shutdown process.exit(); }); 

Answer 3

Currently, node support for capturing Windows console management events is still missing, so there are no POSIX signal equivalents:

https://github.com/joyent/node/issues/1553

However, the tty module documentation provides an example of a keystroke capture mechanism to trigger a graceful shutdown, but then it only works for ctrl + c .

 var tty = require('tty'); process.stdin.resume(); tty.setRawMode(true); process.stdin.on('keypress', function(char, key) { if (key && key.ctrl && key.name == 'c') { console.log('graceful exit of process %d', process.pid); process.exit(); } }); 

Answer 4

I'm not sure when, but on node 8.x and on Windows 10, the source code of the question just works now.

also works with windows command line.

Answer 5

Since node.js 0.8 the keypress event no longer exists. However, there is an npm package called keypress that repeats the event.

Install using npm install keypress , then do something like:

 // Windows doesn't use POSIX signals if (process.platform === "win32") { const keypress = require("keypress"); keypress(process.stdin); process.stdin.resume(); process.stdin.setRawMode(true); process.stdin.setEncoding("utf8"); process.stdin.on("keypress", function(char, key) { if (key && key.ctrl && key.name == "c") { // Behave like a SIGUSR2 process.emit("SIGUSR2"); } else if (key && key.ctrl && key.name == "r") { // Behave like a SIGHUP process.emit("SIGHUP"); } }); }