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Q111001: BUG: PEEKCHARQQ Incorrectly Returning .TRUE.

Article: Q111001
Product(s): Microsoft Fortran Compiler
Version(s): 1.0
Operating System(s): 
Keyword(s): 
Last Modified: 04-NOV-1999

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The information in this article applies to:

- Microsoft Fortran Powerstation 32 for Windows NT, version 1.0 
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SYMPTOMS
========

In a FORTRAN PowerStation application, PEEKCHARQQ may return a value of .TRUE.
even though there is no keystroke waiting in the keyboard buffer.

CAUSE
=====

If GETCHARQQ is not called at least once in the program before calling
PEEKCHARQQ, a call to PEEKCHARQQ will always return .TRUE.. Even after first
calling GETCHARQQ, PEEKCHARQQ, when called repeatedly, may incorrectly return
that a keystroke is available.

STATUS
======

Microsoft has confirmed this to be a problem in FORTRAN PowerStation 32 for
Windows NT, version 1.0. We are researching this problem and will post new
information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION
================

The sample program below should print stars until a key is pressed. However,
after entering a keystroke to start the PEEKCHARQQ loop, stars will stop
printing if no key is pressed. If the call to GETCHARQQ is removed, only one
star will print.

Sample Code
-----------

  C Compile options needed: none
  C

        include 'flib.fi'
        include 'flib.fd'
        character*1 key
        logical pressed/.false./ 
        write(*,*) 'Enter a key to begin test'
        key = GETCHARQQ()      ! Must call GETCHARQQ first
        do while (.NOT. pressed)
           write (*, 900) '*'  ! Print stars until a key is pressed
           pressed = PEEKCHARQQ()
        end do
  900   format (1X, A, \)
        end

Additional query words: 1.00

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Keywords          :  
Technology        : kbAudDeveloper kbFortranSearch kbZNotKeyword2 kbFORTRANPower32100NT
Version           : :1.0

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