just a small OpenCL test

test_opencl.py

from __future__ import print_function
from ctypes import*
import sys

dllname = "opencl"
if len(sys.argv) >= 2:
    dllname = sys.argv[1]
opencl = cdll.LoadLibrary(dllname)
pointerarray_type = c_void_p * 10
platforms = pointerarray_type()
devices = pointerarray_type()
out_num = c_uint()
error = opencl.clGetPlatformIDs(10, platforms, pointer(out_num))

name = (c_char * 256)()

if error == 0:
    for i in range(out_num.value):
        error = opencl.clGetPlatformInfo(c_void_p(platforms[i]), 0x0902, c_size_t(256), pointer(name), 0)
        if error == 0:
            print("Platform {0}: {1}".format(i, name.value.decode()))
            error = opencl.clGetDeviceIDs(c_void_p(platforms[i]), 0xFFFFFFFF, 10, devices, pointer(out_num))
            if error == 0:
                for j in range(out_num.value):
                    error = opencl.clGetDeviceInfo(c_void_p(devices[j]), 0x102B, c_size_t(256), pointer(name), 0)
                    if error == 0:
                        print("\tDevice {0}: {1}".format(j, name.value.decode()))
                    else:
                        print("Device {} has error {}".format(j, error), file=sys.stderr)
            else:
                print("Platform {} has error {}".format(i, error), file=sys.stderr)
        else:
            print("Platform {} has error {}".format(i, error), file=sys.stderr)
else:
    print("Error in clGetPlatformIDs, error code:", error, file=sys.stderr)