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Pure JavaScript tools for buffer (such as concat)


Pure JavaScript utils which extend the global Buffer object in Node.JS.

npm install bufferjs


  • buffer.addChunk(chunk)
  • Buffer.indexOf(haystack, needle, startIndex)
  • buffer.indexOf(needle, startIndex)


Adds a buffer chunk to buffer.

Returns true when full

Returns new Buffer if buffer overflows


var buffer = new Buffer(9),

buffer.addChunk(new Buffer("abc"));
buffer.addChunk(new Buffer("def"));
buffer.toString(); // "abcdef???"
// Note: "???" is whatever random garbage was internally `malloc`d.    

console.log(true === buffer.addChunk(new Buffer("ghi"))); // true, buffer is full
// true when buffer is full

// adding past the index will throw an error
overflow = buffer.addChunk(new Buffer("jkl"));
buffer.toString(); // abcdefghi
overflow.toString(); // jkl

Buffer.indexOf(haystack, needle, startIndex)

Searches the given haystack Buffer for the given needle Buffer. Returns the index of the first occurence of needle, or -1 if the pattern was not found. needle may also be a regular String, for convenience. startIndex tells at which index to begin the search.


var haystack = new Buffer(10);
var needle = '\r\n';
haystack.write(needle, 5);

Buffer.indexOf(haystack, needle); // 5
Buffer.indexOf(haystack, 'NOT_IN_HAYSTACK'); // -1

buffer.indexOf(needle, startIndex)

OO-style variant of Buffer.indexOf. this is the haystack, and only needle needs to be supplied when called.


var haystack = new Buffer(10);
var needle = '\r\n';
haystack.write(needle, 5);

haystack.indexOf(needle); // 5
haystack.indexOf('NOT_IN_HAYSTACK'); // -1

Buffer.concat(list, [totalLength])

Deprecated: Node.JS 0.8.x has Buffer.concat built-in (compatible). See

WARNING: v1.2.1 uses NON-NATIVE concat. v2.0.0 uses NATIVE concat ONLY.

Returns a new Buffer with the contents of all buffers in the Array.


var buffers = [
        new Buffer("abc")
      , new Buffer("def")
      , new Buffer("ghi")
  , buffer

buffer = Buffer.concat(buffers);
// abcdefghi
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