---
title: IOPhysicalLength64
framework: driverkit
role: symbol
role_heading: Type Alias
path: driverkit/iophysicallength64
---

# IOPhysicalLength64

A type that represents the length of a memory block in a 64-bit address space.

## Declaration

```occ
typedef uint64_t IOPhysicalLength64;
```

## See Also

### Addresses

- [IOVirtualAddress](driverkit/iovirtualaddress.md)
- [IOPhysicalAddress](driverkit/iophysicaladdress.md)
- [IOPhysicalAddress32](driverkit/iophysicaladdress32.md)
- [IOPhysicalAddress64](driverkit/iophysicaladdress64.md)
- [IOPhysicalLength](driverkit/iophysicallength.md)
- [IOPhysicalLength32](driverkit/iophysicallength32.md)
- [IOCacheMode](driverkit/iocachemode.md)