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ZJS API for Buffer
==================
* [Introduction](#introduction)
* [Web IDL](#web-idl)
* [API Documentation](#api-documentation)
* [Sample Apps](#sample-apps)
Introduction
------------
Buffer is a [node.js API]
(https://nodejs.org/dist/latest-v6.x/docs/api/buffer.html)
to read and write binary data accurately from JavaScript. ZJS supports a minimal
subset of this API that will be expanded as the need arises.
Web IDL
-------
This IDL provides an overview of the interface; see below for documentation of
specific API functions.
```javascript
// Buffer is a global object constructor that is always available
[Constructor(unsigned long length)]
interface Buffer {
unsigned char readUInt8(unsigned long offset);
void writeUInt8(unsigned char value, unsigned long offset);
unsigned short readUInt16BE(unsigned long offset);
void writeUInt16BE(unsigned short value, unsigned long offset);
unsigned short readUInt16LE(unsigned long offset);
void writeUInt16LE(unsigned short value, unsigned long offset);
unsigned long readUInt32BE(unsigned long offset);
void writeUInt32BE(unsigned long value, unsigned long offset);
unsigned long readUInt32LE(unsigned long offset);
void writeUInt32LE(unsigned long value, unsigned long offset);
string toString(string encoding);
readonly attribute unsigned long length;
};
```
API Documentation
-----------------
### Buffer constructor
`Buffer(unsigned long length);`
The `length` argument specifies the length in bytes of the Buffer object.
### Buffer.readUInt family
```javascript
unsigned char readUInt8(unsigned long offset);
unsigned short readUInt16BE(unsigned long offset);
unsigned short readUInt16LE(unsigned long offset);
unsigned long readUInt32BE(unsigned long offset);
unsigned long readUInt32LE(unsigned long offset);
```
The `offset` should be provided but will be treated as 0 if not given. Returns
the value of the short or long located at the given offset. If the offset is
outside the bounds of the Buffer, returns an error.
The `BE` or `LE` refers to whether the bytes will be read in big-endian
(highest byte first) or little-endian (lowest byte first) order.
### Buffer.writeUInt family
```javascript
void writeUInt8(unsigned char value, unsigned long offset);
void writeUInt16BE(unsigned short value, unsigned long offset);
void writeUInt16LE(unsigned short value, unsigned long offset);
void writeUInt32BE(unsigned long value, unsigned long offset);
void writeUInt32LE(unsigned long value, unsigned long offset);
```
The `offset` should be provided but will be treated as 0 if not given. Writes
`value` to the buffer starting at the given offset. If the target area goes
outside the bounds of the Buffer, returns an error.
The `BE` or `LE` refers to whether the value will be written in big-endian
(highest byte first) or little-endian (lowest byte first) order.
### Buffer.toString
`string toString(string encoding);`
Currently, the only supported `encoding` is 'hex'. If 'hex' is given, returns
the contents of the Buffer encoded in hexadecimal digits. Otherwises, returns an
error.
Sample Apps
-----------
* [Buffer sample](../samples/Buffer.js)
* [WebBluetooth Demo](../samples/WebBluetoothDemo.js)
|
