C Specification

To enqueue a command to fill a buffer object with a pattern of a given pattern size, call the function

// Provided by CL_VERSION_1_2
cl_int clEnqueueFillBuffer(
    cl_command_queue command_queue,
    cl_mem buffer,
    const void* pattern,
    size_t pattern_size,
    size_t offset,
    size_t size,
    cl_uint num_events_in_wait_list,
    const cl_event* event_wait_list,
    cl_event* event);
clEnqueueFillBuffer is missing before version 1.2.

Parameters

  • command_queue refers to the host command-queue in which the fill command will be queued. The OpenCL context associated with command_queue and buffer must be the same.

  • buffer is a valid buffer object.

  • pattern is a pointer to the data pattern of size pattern_size in bytes. pattern will be used to fill a region in buffer starting at offset and is size bytes in size. The data pattern must be a scalar or vector integer or floating-point data type supported by OpenCL as described in Shared Application Scalar Data Types and Supported Application Vector Data Types. For example, if buffer is to be filled with a pattern of float4 values, then pattern will be a pointer to a cl_float4 value and pattern_size will be sizeof(cl_float4). The maximum value of pattern_size is the size of the largest integer or floating-point vector data type supported by the OpenCL device. The memory associated with pattern can be reused or freed after the function returns.

  • offset is the location in bytes of the region being filled in buffer and must be a multiple of pattern_size.

  • size is the size in bytes of region being filled in buffer and must be a multiple of pattern_size.

  • event_wait_list and num_events_in_wait_list specify events that need to complete before this particular command can be executed. If event_wait_list is NULL, then this particular command does not wait on any event to complete. If event_wait_list is NULL, num_events_in_wait_list must be 0. If event_wait_list is not NULL, the list of events pointed to by event_wait_list must be valid and num_events_in_wait_list must be greater than 0. The events specified in event_wait_list act as synchronization points. The context associated with events in event_wait_list and command_queue must be the same. The memory associated with event_wait_list can be reused or freed after the function returns.

  • event returns an event object that identifies this command and can be used to query or queue a wait for this command to complete. If event is NULL or the enqueue is unsuccessful, no event will be created and therefore it will not be possible to query the status of this command or to wait for this command to complete. If event_wait_list and event are not NULL, event must not refer to an element of the event_wait_list array.

Description

The usage information which indicates whether the memory object can be read or written by a kernel and/or the host and is given by the cl_mem_flags argument value specified when buffer is created is ignored by clEnqueueFillBuffer.

clEnqueueFillBuffer returns CL_SUCCESS if the function is executed successfully. Otherwise, it returns one of the following errors:

  • CL_INVALID_COMMAND_QUEUE

    • if command_queue is not a valid host command-queue

  • CL_INVALID_CONTEXT

    • if the context associated with command_queue and buffer are not the same

    • if the context associated with command_queue and events in event_wait_list are not the same

  • CL_INVALID_MEM_OBJECT

    • if buffer is not a valid buffer object

  • CL_INVALID_VALUE

    • if the region being filled specified by offset and size is out of bounds

    • if pattern is NULL

    • if pattern_size is zero

    • if pattern_size is not a power of two

    • if pattern_size is greater than 128

    • if offset is not a multiple of pattern_size

    • if size is not a multiple of pattern_size

  • CL_INVALID_EVENT_WAIT_LIST

    • if event_wait_list is NULL and num_events_in_wait_list is greater than zero

    • if event_wait_list is not NULL and num_events_in_wait_list is zero

    • if event objects in event_wait_list are not valid events

  • CL_MISALIGNED_SUB_BUFFER_OFFSET

    • if buffer is a sub-buffer object and the offset specified when the sub-buffer object was created is not aligned to the CL_DEVICE_MEM_BASE_ADDR_ALIGN value for the device associated with command_queue. This error code is missing before version 1.1.

  • CL_MEM_OBJECT_ALLOCATION_FAILURE

    • if there is a failure to allocate memory for the data store associated with buffer

  • CL_INVALID_OPERATION

    • if buffer was created with CL_MEM_IMMUTABLE_EXT

  • CL_OUT_OF_RESOURCES

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

  • 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_2, cl_command_queue, cl_event, cl_mem, 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