VQueryfNoPoll

Performs a formatted write and read through a single operation invocation, without polling for errors after the read.

Syntax

virtual HRESULT VQueryfNoPoll(const CString strWriteFormat, const CString strReadFormat, va_list& argList, long lTimeout = CUR_TIMEOUT) abstract;

Parameters

strFormat

[in] String describing the format for arguments. See the topic I/O Format Specifiers for Write Operations for details.

argList

[in] Argument list interpreted by the format string.

lTimeout

[in] I/O timeout in milliseconds.

Return value

Returns S_OK if successful, otherwise a failure HRESULT.

Remarks

This function behaves identically to VQueryf except that the device is not polled for errors after the data is read.

Example

The following example demonstrates use of the VQueryf function.

inline HRESULT CIoSession::Queryf(const CString strWriteFormat, const CString strReadFormat, ...)
{
  HRESULT hr = S_OK;

  va_list argList;
  va_start(argList, strReadFormat);

  hr = VQueryf(strWriteFormat, strReadFormat, argList);

  va_end(argList);

  if (SUCCEEDED(hr))
  {
    hr = PollInstrumentErrors();
  }

  return hr;
}