Altitude Property

The altitude the class's system driver should use.

Syntax

 cbregistry.getAltitude([callback])
 cbregistry.setAltitude( altitude, [callback])

Default Value

Callback

The 'callback' parameter specifies a function which will be called when the operation completes (or an error is encountered). If the 'callback' parameter is not specified, then the method will block and will not return until the operation completes (or an error is encountered).

The callback for the getAltitude([callback]) method is defined as:

function(err, data){ }

'err' is the error that occurred. If there was no error, then 'err' is 'null'.

'data' is the value returned by the method.

The callback for the setAltitude([callback]) method is defined as:

function(err){ }

'err' is the error that occurred. If there was no error, then 'err' is 'null'.

'err' has 2 properties which hold detailed information:

err.code
err.message

Remarks

This property specifies the altitude that the class's system driver should use. A driver's altitude determines its absolute position in the stack of filter drivers; drivers with higher altitudes are attached towards the top of the stack, closer to user mode, which allows them to process requests earlier.

Registry filter drivers are not required to specify an altitude; and this property's default value of 0 is interpreted as "no altitude". However, registry filter drivers that don't specify an altitude will always be attached near the top of the filter driver stack, which may not be desirable. Please refer to the Driver Altitudes topic for more information.

Data Type

Integer