WriteInt8ToUser function (usermode_accessors.h)

The WriteInt8ToUser function safely writes an INT8 value to user-mode memory.

Syntax

void WriteInt8ToUser(
  volatile INT8 *Destination,
  INT8          Value
);

Parameters

Destination

[out] A pointer to the user-mode memory location where the INT8 value will be written.

Value

[in] The INT8 value to write to the destination memory location.

Return value

None

Remarks

This function provides a safe way to write an INT8 value to user-mode memory. It ensures the provided address is a user-mode address before writing to it.

This function doesn't enforce alignment.

It raises a structured exception if the memory access fails, such as when the destination address isn't a user-mode address or is inaccessible.

This function will never be optimized away by the compiler, nor will the compiler create additional accesses to this memory location before the function is called or after the function returns (unless the source code explicitly performs these accesses). The memory access is performed with memory_order_relaxed semantics.

This function works on all versions of Windows, not just the latest. You need to consume the latest WDK to get the function declaration from the usermode_accessors.h header. You also need the library (umaccess.lib) from the latest WDK. However, the resulting driver will run fine on older versions of Windows.

Requirements

See also

ReadInt8FromUser

WriteInt8ToMode