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The WriteInt16ToUser function safely writes an INT16 value to user-mode memory.
Syntax
void WriteInt16ToUser(
volatile INT16 *Destination,
INT16 Value
);
Parameters
Destination
[out] A pointer to the user-mode memory ___location where the INT16 value will be written.
Value
[in] The INT16 value to write to the destination memory ___location.
Return value
None
Remarks
This function provides a safe way to write an INT16 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
Requirement | Value |
---|---|
Minimum supported client | See Remarks |
Header | usermode_accessors.h |
Library | umaccess.lib |
IRQL | Less than or equal to APC_LEVEL |