IKsJackDescription::GetJackCount method (devicetopology.h)

Article
10/13/2021

The GetJackCount method gets the number of jacks required to connect to an audio endpoint device.

Syntax

HRESULT GetJackCount(
  [out] UINT *pcJacks
);

Parameters

[out] pcJacks

Pointer to a UINT variable into which the method writes the number of jacks associated with the connector.

Return value

If the method succeeds, it returns S_OK. If it fails, possible return codes include, but are not limited to, the values shown in the following table.

Return code	Description
E_POINTER	Pointer pcJacks is NULL.

Remarks

An audio endpoint device that plays or records a stream that contains multiple channels might require a connection with more than one jack (physical connector).

For example, a set of surround speakers that plays a 6-channel audio stream might require three stereo jacks. In this example, the first jack transmits the channels for the front-left and front-right speakers, the second jack transmits the channels for the front-center and low-frequency-effects (subwoofer) speakers, and the third jack transmits the channels for the side-left and side-right speakers.

After calling this method to retrieve the jack count, call the IKsJackDescription::GetJackDescription method once for each jack to obtain a description of the jack.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	devicetopology.h