Enqueues a command to copy a buffer object to another buffer object.

cl_int clEnqueueCopyBuffer ( cl_command_queue command_queue,
  cl_mem src_buffer,
  cl_mem dst_buffer,
  size_t src_offset,
  size_t dst_offset,
  size_t cb,
  cl_uint num_events_in_wait_list,
  const cl_event *event_wait_list,
  cl_event *event)



The command-queue in which the copy command will be queued. The OpenCL context associated with command_queue, src_buffer, and dst_buffer must be the same.


The offset where to begin copying data from src_buffer.


The offset where to begin copying data into dst_buffer.


Refers to the size in bytes to copy.

event_wait_list, , 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.


Returns an event object that identifies this particular copy command and can be used to query or queue a wait for this particular command to complete. event can be NULL in which case it will not be possible for the application to query the status of this command or queue a wait for this command to complete. clEnqueueBarrier can be used instead.


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 command-queue.
  • CL_INVALID_CONTEXT if the context associated with command_queue, src_buffer, and dst_buffer are not the same or if the context associated with command_queue and events in event_wait_list are not the same.
  • CL_INVALID_MEM_OBJECT if src_buffer and dst_buffer are not valid buffer objects.
  • CL_INVALID_VALUE if src_offset, dst_offset, cb, src_offset + cb, or dst_offset + cb require accessing elements outside the buffer memory objects.
  • CL_INVALID_EVENT_WAIT_LIST if event_wait_list is NULL and num_events_in_wait_list is greater than 0, or event_wait_list is not NULL and num_events_in_wait_list is 0, or if event objects in event_wait_list are not valid events.
  • CL_MEM_COPY_OVERLAP if src_buffer and dst_buffer are the same buffer object and the source and destination regions overlap.
  • CL_MEM_OBJECT_ALLOCATION_FAILURE if there is a failure to allocate memory for data store associated with src_buffer or dst_buffer.
  • CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the OpenCL implementation on the host.


OpenCL Specification

Also see

clEnqueueReadBuffer, clEnqueueWriteBuffer, clCreateBuffer, clEnqueueCopyBufferToImage, clEnqueueCopyImageToBuffer

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