From Facebook Developer Wiki

Contents 1 Description 2 Parameters 3 Response 4 Error Codes 5 Notes

Description

If this method is called for the logged in user, then no further API calls can be made on that user's behalf until the user decides to authorize the application again.

Parameters

Required	Name	Type	Description
required	api_key	string	The application key associated with the calling application. If you specify the API key in your client, you don't need to pass it with every call.
	sig	string	An MD5 hash of the current request and your secret key, as described in the How Facebook Authenticates Your Application. Facebook computes the signature for you automatically.
	v	string	This must be set to 1.0 to use this version of the API. If you specify the version in your client, you don't need to pass it with every call.
optional	uid	int	User whose authorization should be revoked. If not present, then it is expected that a valid session currently exists, and the current user will have their authorization revoked.
	format	string	The desired response format, which can be either XML or JSON. (Default value is XML.)
	callback	string	Name of a function to call. This is primarily to enable cross-domain JavaScript requests using the <script> tag, also known as JSONP, and works with both the XML and JSON formats. The function will be called with the response passed as the parameter.

Response

This method returns true upon success. If the app is not authorized, then return false.

Error Codes

Code	Description
1	An unknown error occurred. Please resubmit the request.
2	The service is not available at this time.
101	The API key submitted is not associated with any known application.
102	The session key does not exist or has expired.
104	Incorrect signature.

Notes

• This method does not require a session_key, unless it is being called by a desktop application.
• You can call this method using a session secret, and not the application secret (for example, for a Facebook Connect site or desktop application).