WritePrinter

BOOL WritePrinter(
  HANDLE  hPrinter,     /* handle of printer object                  */
  LPVOID  pBuf,         /* address of array containing printer dataa */
  DWORD   cbBuf,        /* size, in bytes, of array                  */
  LPDWORD lpdwWritten   /* addr. of variable with written byte count */
);

Informs the print spooler that the specified data should be written to the specified printer.

If the function succeeds, the return value is TRUE; otherwise, it is FALSE. To get extended error information, use the GetLastError function.

hPrinter	Identifies the printer.
pBuf	Points to an array of bytes that contains the data that should be written to the printer.
cbBuf	Specifies the size, in bytes, of the array.
lpdwWritten	Points to a value that specifies the number of bytes of data that were written to the printer.