C Specification

The list of platforms available can be obtained with the function:

// Provided by CL_VERSION_1_0
cl_int clGetPlatformIDs(
    cl_uint num_entries,
    cl_platform_id* platforms,
    cl_uint* num_platforms);

Parameters

  • num_entries is the number of cl_platform_id entries that can be added to platforms. If platforms is not NULL, num_entries must be greater than zero.

  • platforms returns a list of OpenCL platforms found. The cl_platform_id values returned in platforms can be used to identify a specific OpenCL platform. If platforms is NULL, this argument is ignored. The number of OpenCL platforms returned is the minimum of the value specified by num_entries or the number of OpenCL platforms available.

  • num_platforms returns the number of OpenCL platforms available. If num_platforms is NULL, this argument is ignored.

Description

clGetPlatformIDs returns CL_SUCCESS if the function is executed and, if the cl_khr_icd extension is supported, there are a non-zero number of platforms available. Otherwise, it returns one of the following errors:

  • CL_PLATFORM_NOT_FOUND_KHR

    • if the cl_khr_icd extension is supported and zero platforms are available

  • CL_INVALID_VALUE

    • if num_entries is equal to zero and platforms is not NULL

    • if both num_platforms and platforms are NULL

  • CL_OUT_OF_HOST_MEMORY

    • if there is a failure to allocate resources required by the OpenCL implementation on the host

See Also

CL_VERSION_1_0, cl_platform_id, cl_uint

Document Notes

For more information, see the OpenCL Specification

This page is extracted from the OpenCL 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