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# dispatch_data_applier_t

A block to invoke for every contiguous memory region in a data object.

```
typedef _Bool (^)(NSObject<OS_dispatch_data> *, unsigned long, const void *, unsigned long) dispatch_data_applier_t;
```

## Discussion

The parameters of a dispatch data applier block are as follows:

- `region` - A data object containing the current memory region being analyzed.
- `offset` - The logical offset to the current region from the start of the data object.
- `buffer` - A pointer to the memory for the current region.
- `size` - The size of the memory for the current region.

This handler returns a Boolean value indicating whether traversal of the region should continue.

---

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