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_RPT, _RPTF Macros
Track an application's progress by generating a debug report (debug version only).
_RPT0( reportType, format ); _RPT1( reportType, format, arg1 ); _RPT2( reportType, format, arg1, arg2 ); _RPT3( reportType, format, arg1, arg2, arg3 ); _RPT4( reportType, format, arg1, arg2, arg3, arg4 ); _RPTF0( reportType, format ); _RPTF1( reportType, format, arg1 ); _RPTF2( reportType, format, arg1, arg2 ); _RPTF3( reportType, format, arg1, arg2, arg3 ); _RPTF4( reportType, format, arg1, arg2, arg3, arg4 );
- Report type: _CRT_WARN, _CRT_ERROR, _CRT_ASSERT.
- Format-control string used to create the user message.
- Name of first substitution argument used by format.
- Name of second substitution argument used by format.
- Name of third substitution argument used by format.
- Name of fourth substitution argument used by format.
All of these macros take the reportType and format parameters. In addition, they might also take arg1 through arg4, signified by the number appended to the macro name. For example, _RPT0 and _RPTF0 take no additional arguments, _RPT1 and _RPTF1 take arg1, _RPT2 and _RPTF2 take arg1 and arg2, and so on.
The _RPT and _RPTF macros are similar to the printf function, as they can be used to track an application's progress during the debugging process. However, these macros are more flexible than printf because they do not need to be enclosed in #ifdef statements to prevent them from being called in a retail build of an application. This flexibility is achieved by using the _DEBUG macro; the _RPT and _RPTF macros are only available when the _DEBUG flag is defined. When _DEBUG is not defined, calls to these macros are removed during preprocessing.
The _RPT macros call the _CrtDbgReport function to generate a debug report with a user message. The _RPTF macros create a debug report with the source file and line number where the report macro was called, in addition to the user message. The user message is created by substituting the arg[n] arguments into the format string, using the same rules defined by the printf function.
_CrtDbgReport generates the debug report and determines its destination(s), based on the current report modes and file defined for reportType. The _CrtSetReportMode and _CrtSetReportFile functions are used to define the destination(s) for each report type.
If an _RPT macro is called and neither _CrtSetReportMode nor _CrtSetReportFile has been called, messages are displayed as follows,
|Report type||Output destination|
|_CRT_WARN||Warning text is not displayed.|
|_CRT_ERROR||A pop-up window. Same as if |
|_CRT_ASSERT||Same as _CRT_ERROR.|
When the destination is a debug message window and the user chooses the Retry button, _CrtDbgReport returns 1, causing these macros to start the debugger, provided that "just-in-time" (JIT) debugging is enabled. For more information about using these macros as a debugging error handling mechanism, see Using Macros for Verification and Reporting.
Two other macros exist that generate a debug report. The _ASSERT macro generates a report, but only when its expression argument evaluates to FALSE. _ASSERTE is exactly like _ASSERT, but includes the failed expression in the generated report.
|_RPT macros||<crtdbg.h>||Win 98, Win Me, Win NT, Win 2000, Win XP|
|_RPTF macros||<crtdbg.h>||Win 98, Win Me, Win NT, Win 2000, Win XP|
For additional compatibility information, see Compatibility in the Introduction.
Debug versions of C run-time libraries only.
Although these are macros and are obtained by including CRTDBG.H, the application must link with one of the debug libraries because these macros call other run-time functions.
See the example in the _ASSERT topic.