## C Specification

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

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, the 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 successfully. Otherwise, it returns one of the following errors:

• CL_​INVALID_​VALUE if num_entries is equal to zero and platforms is not NULL or 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.