bytebeat.js

// bytebeat.js
// Run using node like this:
// node bytebeat.js < input.js | pacat --format=u8 --channels=1 --rate=8000 (PulseAudio)
// node bytebeat.js < input.js | aplay --rate=8000 (ALSA)

function dataread(buf) {
    expr += buf;
}

if (process.stdout.isTTY) {
    console.log('stdout = tty, exiting');
    process.exit(1);
}

var CHUNK = 1024;
var LIM = Number(process.argv[2]) || -1;
var expr = 'return ';

process.stdin.on('data', function(buf) {
    expr += buf;
});

process.stdin.on('end', function() {
    var fun = new Function('t', expr);
    var t = 0;
    function write() {
        var ok = true;
        while (ok && (t < LIM || LIM == -1)) {
            var data = new Buffer(CHUNK);
            for (var k = 0; k < CHUNK; ++k) {
                data[k] = fun(t+k);
            }
            ok = process.stdout.write(data);
            t += CHUNK;
        }
        if (t < LIM || LIM == -1) {
            process.stdout.once('drain', write);
        }
    };
    write();
});