# vkGetSwapchainCounterEXT(3) Manual Page

## Name

vkGetSwapchainCounterEXT - Query the current value of a surface counter

## C Specification

The requested counters become active when the first presentation command for the associated swapchain is processed by the presentation engine. To query the value of an active counter, use:

    VkResult vkGetSwapchainCounterEXT(
        VkDevice                                    device,
        VkSwapchainKHR                              swapchain,
        VkSurfaceCounterFlagBitsEXT                 counter,
        uint64_t*                                   pCounterValue);

## Parameters

- `device` is the VkDevice associated with `swapchain`.

- `swapchain` is the swapchain from which to query the counter value.

- `counter` is the counter to query.

- `pCounterValue` will return the current value of the counter.

## Description

If a counter is not available because the swapchain is out of date, the implementation may return `VK_ERROR_OUT_OF_DATE_KHR`.

Valid Usage

- One or more present commands on `swapchain` must have been processed by the presentation engine.

Valid Usage (Implicit)

- `device` must be a valid VkDevice handle

- `swapchain` must be a valid VkSwapchainKHR handle

- `counter` must be a valid VkSurfaceCounterFlagBitsEXT value

- `pCounterValue` must be a valid pointer to a `uint64_t` value

- Both of `device`, and `swapchain` must have been created, allocated, or retrieved from the same VkInstance

Return Codes

On success, this command returns

  - `VK_SUCCESS`

On failure, this command returns

  - `VK_ERROR_DEVICE_LOST`

  - `VK_ERROR_OUT_OF_DATE_KHR`

## See Also

VkDevice, VkSurfaceCounterFlagBitsEXT, VkSwapchainKHR

## Document Notes

For more information, see the Vulkan Specification

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

## Copyright

Copyright (c) 2014-2020 Khronos Group. This work is licensed under a Creative Commons Attribution 4.0 International License.