diff --git a/doc/api/stream.markdown b/doc/api/stream.markdown index 768b7d2ad4e782..ecb17413722c7a 100644 --- a/doc/api/stream.markdown +++ b/doc/api/stream.markdown @@ -167,6 +167,32 @@ again when more data is available. The `readable` event is not emitted in the "flowing" mode with the sole exception of the last one, on end-of-stream. +Note that the `'readable'` event indicates only that data *can* be +read from the stream. It does not indicate whether there is actual +data to be consumed. The callback passed to handle the `'readable'` +event must be prepared to handle a `null` response from +`readable.read([size])`. For instance, in the following example, `foo.txt` +is an empty file: + +```javascript +var fs = require('fs'); +var rr = fs.createReadStream('foo.txt'); +rr.on('readable', function() { + console.log('readable:', rr.read()); +}); +rr.on('end', function() { + console.log('end'); +}); +``` + +The output of running this script is: + +``` +bash-3.2$ node test.js +readable: null +end +``` + #### Event: 'data' * `chunk` {Buffer | String} The chunk of data.