nf-fdi-fnwrite.md

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NF:fdi.FNWRITE	FNWRITE macro (fdi.h)	The FNWRITE macro provides the declaration for the application-defined callback function to write data to a file in an FDI context.	FNWRITE FNWRITE macro [Windows API] fdi/FNWRITE winprog.fnwrite	winprog\fnwrite.htm	winprog	e15d4293-2955-48cd-b8c9-77669a1e6436	12/05/2018	FNWRITE, FNWRITE macro [Windows API], fdi/FNWRITE, winprog.fnwrite	fdi.h		Windows															Windows			19H1	FNWRITE fdi/FNWRITE	c++	APIRef kbSyntax	HeaderDef	fdi.h	FNWRITE

-description

The FNWRITE macro provides the declaration for the application-defined callback function to write data to a file in an FDI context.

-parameters

-param fn [in]

An application-defined value used to identify the open file.

-remarks

The function accepts parameters similar to _write.

Examples

FNWRITE(fnFileWrite)
{
    DWORD dwBytesWritten = 0;

    if ( WriteFile((HANDLE)hf, pv, cb, &dwBytesWritten, NULL) == FALSE )
    {
        dwBytesWritten = (DWORD)-1;
    }

    return dwBytesWritten;
}

-see-also

FDICreate