typedef void *(*bson_realloc_func) (void *mem, size_t num_bytes, void *ctx);

       MongoDB, Inc

       2009-present, MongoDB, Inc.

1.30.4                                            Jun 08, 2025                              BSON_REALLOC_FUNC(3)

       This  is a prototype for pluggable realloc functions used through the Libbson library. If you wish to use
       a custom allocator this is one way to do it. Additionally, bson_realloc_ctx() is a default implementation
       of this prototype.

       • mem: A memory region.

       • num_bytes: A size_t containing the requested size.

       • ctx: A consumer-specific pointer or NULL.

          typedef void *(*bson_realloc_func) (void *mem, size_t num_bytes, void *ctx);