Detecting Data on the Communications Port

 Last reviewed: December 16, 1996
Article ID: Q118625
The information in this article applies to:
  • Microsoft Win32 Application Programming Interface (API) included with: 

        - Microsoft Windows NT versions 3.1, 3.5, 3.51, and 4.0
    - Microsoft Windows 95 version 4.0

To detect whether there is any data available on the communications (COM) port without calling ReadFile(), use the ClearCommError() API. The field COMSTAT.CbInQue contains the number of bytes not yet read by a call to ReadFile().

Additional reference words: 3.10 3.50 3.51 4.00 95
KBCategory: kbprg
KBSubcategory: BseCommapi

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Last reviewed: December 16, 1996
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