C Specification

To query the available instance extensions, call:

VkResult vkEnumerateInstanceExtensionProperties(
    const char*                                 pLayerName,
    uint32_t*                                   pPropertyCount,
    VkExtensionProperties*                      pProperties);


  • pLayerName is either NULL or a pointer to a null-terminated UTF-8 string naming the layer to retrieve extensions from.

  • pPropertyCount is a pointer to an integer related to the number of extension properties available or queried, as described below.

  • pProperties is either NULL or a pointer to an array of VkExtensionProperties structures.


When pLayerName parameter is NULL, only extensions provided by the Vulkan implementation or by implicitly enabled layers are returned. When pLayerName is the name of a layer, the instance extensions provided by that layer are returned.

If pProperties is NULL, then the number of extensions properties available is returned in pPropertyCount. Otherwise, pPropertyCount must point to a variable set by the user to the number of elements in the pProperties array, and on return the variable is overwritten with the number of structures actually written to pProperties. If pPropertyCount is less than the number of extension properties available, at most pPropertyCount structures will be written. If pPropertyCount is smaller than the number of extensions available, VK_INCOMPLETE will be returned instead of VK_SUCCESS, to indicate that not all the available properties were returned.

Because the list of available layers may change externally between calls to vkEnumerateInstanceExtensionProperties, two calls may retrieve different results if a pLayerName is available in one call but not in another. The extensions supported by a layer may also change between two calls, e.g. if the layer implementation is replaced by a different version between those calls.

Valid Usage
Valid Usage (Implicit)
  • If pLayerName is not NULL, pLayerName must be a null-terminated string

  • pPropertyCount must be a pointer to a uint32_t value

  • If the value referenced by pPropertyCount is not 0, and pProperties is not NULL, pProperties must be a pointer to an array of pPropertyCount VkExtensionProperties structures

Return Codes
On success, this command returns


On failure, this command returns



See Also

Document Notes

For more information, see the Vulkan Specification at URL

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification,not directly.

Copyright (c) 2014-2016 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.