TBApiGetRelativeDevice API Call

 

Description

Gets a device handle at a given position in the list of defined devices.

Parameters

An integer argument containing the device position offset. 0 = first device, 1 = second and so forth.

Returns

The device handle or a return value of TB_INVALID_HANDLE_VALUE meaning that the requested device does not exist.

Notes

This call is typically used to get the only device in a single device or if you want to iterate API calls through all controllers, Use other API calls to find a specific controller on the system, e.g. TBApiGetNamedDevice.

Applications should always call TBApiGetRelativeDevice before calling a specific API as it is possible that the Device Identifier could change if the controllers are reconfigured.

See also

A number of functions require a device handle. The following family of functions provide valid device handle’s:

 

TBApiGetRelativeDevice

Get device handle from position

 

TBApiGetRelativeDeviceFromHandle

Get position from device handle

 

TBApiGetRelativeDeviceNoHidden

Get device handle from position, excluding hidden (unplugged) devices

 

TBApiGetRelativeDeviceIncHidden

Get device handle from position, including hidden (unplugged) devices

 

TBApiGetNamedDevice

Get device handle from named device

 

TBApiGetDeviceFromSegment

Get device handle from segment

 

Visual C++ Declaration/example

 

HTBDEVICE TBAPI TBApiGetRelativeDevice(int o);

 

// Gets the first device on the system, you can use

HTBDEVICE device = TBApiGetRelativeDevice(0);

 

// …or to enumerate all devices e.g.

HTBDEVICE device = TBApiGetRelativeDevice(0);

for(int i=0; device != TB_INVALID_HANDLE_VALUE;)

{

   DoSomethingWithDevice(device);

   device = TBApiGetRelativeDevice(++i);

}

 

Visual Basic Declaration/example

 

Public Declare Function TBApiGetRelativeDevice Lib "TBapi" Alias "_DLL_TBApiGetRelativeDevice@4" (ByVal offset as Integer) As Byte

 

Dim device as Byte

device = TBApiGetRelativeDevice(1)