vkSignalSemaphore(3)

# vkSignalSemaphore(3) Manual Page

## Name

vkSignalSemaphore - Signal a timeline semaphore on the host

## C Specification

To signal a semaphore created with a VkSemaphoreType of VK_SEMAPHORE_TYPE_TIMELINE with a particular counter value, on the host, call:

    // Provided by VK_VERSION_1_2
    VkResult vkSignalSemaphore(
        VkDevice                                    device,
        const VkSemaphoreSignalInfo*                pSignalInfo);

    // Provided by VK_KHR_timeline_semaphore
    // Equivalent to vkSignalSemaphore
    VkResult vkSignalSemaphoreKHR(
        VkDevice                                    device,
        const VkSemaphoreSignalInfo*                pSignalInfo);

## Parameters

- `device` is the logical device that owns the semaphore.

- `pSignalInfo` is a pointer to a VkSemaphoreSignalInfo structure containing information about the signal operation.

## Description

When `vkSignalSemaphore` is executed on the host, it defines and immediately executes a semaphore signal operation which sets the timeline semaphore to the given value.

The first synchronization scope is defined by the host execution model, but includes execution of `vkSignalSemaphore` on the host and anything that happened-before it.

The second synchronization scope is empty.

Valid Usage (Implicit)

- VUID-vkSignalSemaphore-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkSignalSemaphore-pSignalInfo-parameter
  `pSignalInfo` must be a valid pointer to a valid VkSemaphoreSignalInfo structure

Return Codes

On success, this command returns

  - VK_SUCCESS

On failure, this command returns

  - VK_ERROR_OUT_OF_DEVICE_MEMORY

  - VK_ERROR_OUT_OF_HOST_MEMORY

  - VK_ERROR_UNKNOWN

  - VK_ERROR_VALIDATION_FAILED

## See Also

VK_KHR_timeline_semaphore, VK_VERSION_1_2, VkDevice, VkSemaphoreSignalInfo

## 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 2014-2026 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0