LabWindows/CVI Release Notes for Windows
28
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National Instruments Corporation
To solve this dilemma, you can use
CVIRTEHasBeenDetached
in the Utility Library. It is
always safe to call
CVIRTEHasBeenDetached
.
CVIRTEHasBeenDetached
returns FALSE
until the main Run-time Engine DLL,
cvirte.dll
, receives the
PROCESS_DETACH
message. Consequently, if
CVIRTEHasBeenDetached
returns FALSE, your DLL can safely
call functions in the LabWindows/CVI Run-time Engine to release resources.
Note
The Run-time Engine DLL contains the ANSI C, DDE, Formatting and I/O,
RS-232, TCP, User Interface, and Utility libraries.
Use of Run State Change Callbacks: Clarification
You can include run state change callbacks in DLLs you build in LabWindows/CVI. When
running a program in LabWindows/CVI, a run state change callback receives notification
when the program starts, suspends, resumes, and stops. If you include a run state change
callback in a DLL, you must take special care. Refer to the Notification of Changes in Run
State section in Chapter 2, Using Loadable Compiled Modules, in the Programmer Reference
Manual for a detailed discussion of run state change callbacks.
Changes to the ANSI C Library
This section contains information on changes to the ANSI C Library and corrections to the
documentation.
Time and Date Functions
The time and date functions of the ANSI C Library include several changes.
Time Zone Bugs Fixed on Windows 95/NT
In the previous version of LabWindows/CVI, functions such as
localtime
that require time
zone information operate incorrectly in some cases on Windows 95/NT.
The LabWindows/CVI ANSI C Library incorrectly interprets the Windows time zone
information in time zones east of Greenwich Mean Time. This problem occurs only if the
TZ
environment variable is not available. LabWindows/CVI 5.0 corrects this problem.
The library incorrectly determined that daylight savings time was in effect in areas that do not
observe daylight savings time. The library now honors the Windows time zone information
when it indicates that daylight savings time is not observed. For example, there is an Arizona
time zone shown in the Time Zone tab of the Windows Date/Time Properties dialog box.
The system information for the Arizona time zone indicates that daylight savings time is not
observed.
Summary of Contents for Window
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