# dispatch_data_create_map Returns a new dispatch data object containing a contiguous representation of the specified object’s memory. ``` extern dispatch_data_tdispatch_data_create_map(dispatch_data_t data, const void **buffer_ptr, size_t *size_ptr); ``` ## Parameters `data` A dispatch data object containing the memory to map. If the object contains multiple noncontiguous memory regions, those regions are copied to a single, contiguous memory region for the new object. `buffer_ptr` On input, a pointer to a variable in which to store the pointer to the memory region for the newly created dispatch data object. You may specify `NULL` for this parameter if you do not need the information. `size_ptr` On input, a pointer to a variable in which to store the size of the contiguous memory region in the newly created dispatch data object. You may specify `NULL` for this parameter if you do not need the information. ## Return Value A new dispatch data object containing the contiguous version of the memory managed by the object in the `data` parameter. ## Discussion If you specify non-`NULL` values for `buffer_ptr` or `size_ptr`, the values returned in those variables are valid only until you release the newly created dispatch data object. You can use these values as a quick way to access the data of the new data object. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)