stream-copy

Copy writable streams to other writable streams.

stream-copy

Copy writable stream to multiple writable streams.

npm install --global stream-copy

Copy process.stdout to a file:

var stream = require('stream');
stream.copy = require('stream-copy').copy;
stream.copy(process.stdout, fs.createWriteStream(filename));

You can copy to multiple streams:

stream.copy(origin, stream1, stream2...)