Node.js, MongoDB, and AngularJS Web Development

Concatenating Buffers

You can concatenate two or more Buffer objects together to form a new buffer. The concat(list, [totalLength]) method accepts an array of Buffer objects as the first parameter and totalLength, defining the maximum bytes in the buffer, as an optional second argument. The Buffer objects are concatenated in the order in which they appear in the list, and a new Buffer object is returned, containing the contents of the original buffers up to totalLength bytes.

If you do not provide a totalLength parameter, concat() figures out the total length for you. However, it has to iterate through the list, so providing a totalLength value is a bit faster.

The code in Listing 5.5 illustrates concatenation by concatenating a base Buffer