Writes data to the specified file or device. Data may be written asynchronously or synchronously.

BOOLEAN WriteRtFile(
    RTHANDLE hFile, 
    LPVOID lpBuffer, 
    DWORD cbBufferSize, 
    LPDWORD lpcbBytesWritten, 
    LPASYNCIO lpAsync); 

Parameters

hFile

A handle for a file object

lpBuffer

A pointer to a contiguous buffer where the data is stored.

cbBufferSize

The size in bytes of the buffer

lpcbBytesWritten

A pointer to a variable where the number of bytes written in the operation is actually stored (synchronous operation only).

lpAsync

A pointer to an ASYNCIOH structure which has been initialized, or NULL if the operation is to be synchronous.

Remarks

A synchronous operation is started by supplying NULL for the lpAsynch parameter, and returns after the operation is complete, or an error was detected. If the operation was successful, and a non-null value has been provided for lpcbBytesWritten, then the actual count of bytes written is returned through that pointer.

An asynchronous operation is started by supplying a pointer to an initialized ASYNCIO structure in the lpAsync parameter, and the function returns after the parameters have been verified and the write operation has been started but before the entire operation has completed.

The structure must be initialized with at least a handle for a data mailbox through which the ASYNCIO structure is returned on completion of the operation. To complete the operation, wait on the mailbox for the structure to be returned, or call WaitForRtIo with the file handle and the same async pointer supplied to the WriteRtFile call.

Return value

Returns TRUE on success, else FALSE on failure. Status codes returned by GetLastRtError on failure include:

Requirements