C Specification
To export a POSIX file descriptor representing the payload of a fence, call:
// Provided by VK_KHR_external_fence_fd
VkResult vkGetFenceFdKHR(
VkDevice device,
const VkFenceGetFdInfoKHR* pGetFdInfo,
int* pFd);
Parameters
-
device
is the logical device that created the fence being exported. -
pGetFdInfo
is a pointer to a VkFenceGetFdInfoKHR structure containing parameters of the export operation. -
pFd
will return the file descriptor representing the fence payload.
Description
Each call to vkGetFenceFdKHR
must create a new file descriptor and
transfer ownership of it to the application.
To avoid leaking resources, the application must release ownership of the
file descriptor when it is no longer needed.
Note
Ownership can be released in many ways.
For example, the application can call |
If pGetFdInfo->handleType
is
VK_EXTERNAL_FENCE_HANDLE_TYPE_SYNC_FD_BIT
and the fence is signaled at
the time vkGetFenceFdKHR
is called, pFd
may return the value
-1
instead of a valid file descriptor.
Where supported by the operating system, the implementation must set the
file descriptor to be closed automatically when an execve
system call
is made.
Exporting a file descriptor from a fence may have side effects depending on the transference of the specified handle type, as described in Importing Fence State.
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.