I want to print a simple message in mrhof function.
in core>net>rpl I write mrhof.c in makefile. then in rpl-conf.h I change RPL_DAG_MC_NONE to RPL_DAG_MC_ENERGY.
in mrhof.c in calculate_path_metric there is a message to print. for example I want to print Energy.
when I run one of examples like udp-rpl in cooja why I can't see the message in mote output?
It seems that your message use PRINTF macro. All PRINTFs (capped) are macros for printf (small).
For enabling this macro you should change the DEBUG constant value.
Add this to your code:
#define DEBUG DEBUG_PRINT
This snippet would enable your PRINTF macros.
For disabling debug mode and not printing any message written by PRINTF macro change to this:
#define DEBUG DEBUG_NONE
Related
I'm maintaining a C++ COM project. There are some trace lines like ATLTRACE(message);
I searched ATLTRACE. MSDN told Visual C++ output window will display it. However, the product is a release one. The customer won't have the source nor to debug it in VS. So is there any other convenient way to see it? Will Windows Event viewer catch that? Or I have to change the code? Win7, VS2013
The ATLTRACE only uses only the debug output and it works only in the Debug version!
So you may give the enduser a debug version for testing purpose, and use DebugView from Sysinternals. But this may be complicated because you also have to over the debug runtimes that are not redistributable.
But you can easily write your own MY_TRACE macro that has the same functionality.
#define MY_TRACE GetMyTracer() // returns object of CMyTracer
...
class CMyTracer
{
...
// Helper operator to get the trace commands. They call the TraceV functions
void operator()(PCSTR pszFormat, ...);
void operator()(PCWSTR pszFormat, ...);
// Worker functions that do the real job calling TraceV functions
void Trace(PCSTR pszFormat, ...);
void Trace(PCWSTR pszFormat, ...);
// Allowed to be virtual to do some internal mystique stuff, like redirecting and this functions perform all output...
virtual void TraceV(PCSTR pszFormat, va_list args);
virtual void TraceV(PCWSTR pszFormat, va_list args);
...
Now you can use this instead of ATLTRACE
...
MYTRACE("Simple output\n");
MYTRACE("More complex output %d\n", 4711);
Note: It is not wise to replace all ATLTRACE macros with your own replacement. You may spread your trace output onto locations were it don't have impact un speed, but is worth the information.
ATLTRACE is a macro that compiles to nothing in a release build. You'll need to rebuild the project with the _DEBUG macro defined (see <atltrace.h>) to get those to display. However, output generated by ATLTRACE is a debug output string, and will typically only display in the debugger's output window.
If there is important information you need, and if it is in code you control, you'll be better off changing the ATLTRACE macro usage to something else, to either log to the event log or a log file the customer can send to you.
As mentioned by 1201ProgramAlarm, release builds of ATL projects have ATLTRACE macros evaluated to nothing and the binary has no real code generated for respective source code lines. That is, you cannot see the output without altering source code.
In order to not alter the project much, you can redefine the tracing macro itself and produce release build with tracing capabilities where output is routed as defined by you, for example to standard debug output using OutputDebugString API.
See:
How to enable the TRACE macro in Release mode?
AtlReleaseTrace
I'm using Qt5.9, a simple check:
assert(pobjNode != NULL);
Will cause the Qt Signal Received error dialog to be displayed which doesn't give any helpful information about where the problem is or what it is.
Is there a way to replace this useless information with something a bit more helpful?
What I'm thinking of is a way to set-up the dialog to display what could be an error in the event of an error.
Q_ASSERT is a custom assert macro which supposedly enhances the standard assert function.
The error message is handled by qFatal(), which can behave slightly better on some platforms than the standard assert macro. For example on Windows it will trigger the Visual Studio debugger at the point where the assertion fails instead of just calling abort().
You can also redirect the output of Qt error message functions such as qFatalto your custom message handler ( with qInstallMessageHandler() ). It can be useful for example if you want to redirect the errors message to a file.
Also note that Q_ASSERT is disabled with the macro QT_NO_DEBUG(while assert is disabled by NDEBUG) : this can be used to separate your asserts between Qt-related code and the rest.
Q_ASSERT_X Prints the message what together with the location where, the source file name and line number if test is false.
Prints the message what together with the location where, the source file name and line number if test is false.
Example:
// File: div.cpp
#include <QtGlobal>
int divide(int a, int b)
{
Q_ASSERT_X(b != 0, "divide", "division by zero");
return a / b;
}
to read more on test and debug.
You might define your own MY_ASSERT macro. On Linux it could even call another function which uses Glibc backtrace functions or Ian Taylor's libbacktrace library (provided your code is compiled with DWARF debug information using g++ -g) and perhaps display such information in a modal dialog, or on stderr. However, it should probably not return. Read also about Qt and Unix signals and signal-safety(7).
But assert detects a bug which you should correct. Try hard to avoid shipping code with such programmer bugs.
On Linux, the usual assert -it is a macro defined in /usr/include/assert.h- will call on failure __assert_fail (in your C library, but you might redefine it yourself) which would indirectly call abort which indirectly makes a core dump which you can inspect post-mortem using the gdb debugger. You only need to enable core dumps (using ulimit -c builtin in your bash terminal).
Is there a better, maybe more industry standard way to turn on and off debug logging throughout your code?
What I have currently is something similar to this:
#define logging
[.. in several places throughout the code ..]
#ifdef logging
cout << "My debug messages\n";
#endif
I just comment out the #define logging when it's no longer needed.
A couple of shortcomings with this approach seem to be:
I have to #define logging in every file I want to use it in
It's not very robust; I would prefer something like #define logging 1, and be able to check which logging-level is enabled to determine the granularity of my debug output. Unfortunately, to my knowledge, #ifdef doesn't care what value you choose, it just cares that it's defined
Are there any suggestions on how to better implement this?
It's not very robust; I would prefer something like #define logging 1, and be able to check which logging-level is enabled to determine the granularity of my debug output.
Well why don't you do that? Just don't test with #ifdef, but with #if:
#if logging>1
// something
#endif
Also - you could define logging in a separate file (like myDefines.h) and include it in your other files.
//myDefines.h
#define logging 2
//someOtherFile.h
#include "myDefines.h"
#if logging>1
// something
#endif
One suggestion:
You can #define logging in your project settings instead of in every file that you want to use it in.
You may want to checkout Google's glog project: https://code.google.com/p/google-glog/
But this might be more overhead than your're looking for.
Something simple you can try, granted your
compiler supports the -Dmacroname flag, you can turn
on logging with during compile time. For example:
g++ -Dlogging program.cpp -o program
will define the logging macro to 1.
How do I print on the output window in Visual C++? The project that I am working on isn't of a console window project type. That's when I build and run it, it doesn't open a console window. Instead, it opens a win32 application, which isn't built by me. I am just adding things to it.
I am pretty new to C++ and because I couldn't print variables out on any console, it makes it very hard for me to debug.
Since the Visual Studio 2010 project doesn't launch console when I build and run it, can I still print outputs such as variables and others on the Output window of the IDE?
Thanks for any help.
You can use OutputDebugString("..."); to print to the Output window of Visual Studio. You have to #include <windows.h> though.
I have written a portable TRACE macro.
On MS-Windows, it is based on OutputDebugString as indicated by other answers.
Here I share my work:
#ifdef ENABLE_TRACE
# ifdef _MSC_VER
# include <windows.h>
# include <sstream>
# define TRACE(x) \
do { std::stringstream s; s << (x); \
OutputDebugString(s.str().c_str()); \
} while(0)
# else
# include <iostream>
# define TRACE(x) std::clog << (x)
# endif // or std::cerr << (x) << std::flush
#else
# define TRACE(x)
#endif
example:
#define ENABLE_TRACE //can depend on _DEBUG or NDEBUG macros
#include "my_above_trace_header.h"
int main (void)
{
int v1 = 123;
double v2 = 456.789;
TRACE ("main() v1="<< v1 <<" v2="<< v2 <<'\n');
}
Please feel free to give any improvements/suggestions/contributions ;-)
Instead of printing to the Output window in VS as indicated by other answers, I prefer to create a console window in my GUI apps, then use regular printf or cout to write debugging info to it. This has the benefit that you can do it even when you run without the debugger.
See this site for a simple function that sets up a console.
I have used this in the past, although not with a win32 application. You could give it a shot though :)
http://www.cplusplus.com/forum/lounge/17371/
You can use the Windows function OutputDebugString (see here) to send output to debuggers. These outputs are shown in the VS output window. You can also watch these outputs with external applications, e.g. DebugView.
Remember to remove these statements from your production code if you don't want other people to see these debug messages (which would otherwise be possible using tools like DebugView...)
In MFC C++ (Visual Studio 6) I am used to using the TRACE macro for debugging. Is there an equivalent statement for plain win32?
_RPTn works great, though not quite as convenient. Here is some code that recreates the MFC TRACE statement as a function allowing variable number of arguments. Also adds TraceEx macro which prepends source file and line number so you can click back to the location of the statement.
Update: The original code on CodeGuru wouldn't compile for me in Release mode so I changed the way that TRACE statements are removed for Release mode. Here is my full source that I put into Trace.h. Thanks to Thomas Rizos for the original:
// TRACE macro for win32
#ifndef __TRACE_H__850CE873
#define __TRACE_H__850CE873
#include <crtdbg.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#ifdef _DEBUG
#define TRACEMAXSTRING 1024
char szBuffer[TRACEMAXSTRING];
inline void TRACE(const char* format,...)
{
va_list args;
va_start(args,format);
int nBuf;
nBuf = _vsnprintf(szBuffer,
TRACEMAXSTRING,
format,
args);
va_end(args);
_RPT0(_CRT_WARN,szBuffer);
}
#define TRACEF _snprintf(szBuffer,TRACEMAXSTRING,"%s(%d): ", \
&strrchr(__FILE__,'\\')[1],__LINE__); \
_RPT0(_CRT_WARN,szBuffer); \
TRACE
#else
// Remove for release mode
#define TRACE ((void)0)
#define TRACEF ((void)0)
#endif
#endif // __TRACE_H__850CE873
From the msdn docs, Macros for Reporting:
You can use the _RPTn, and _RPTFn macros, defined in CRTDBG.H, to replace the use of printf statements for debugging. These macros automatically disappear in your release build when _DEBUG is not defined, so there is no need to enclose them in #ifdefs.
There is also OutputDebugString. However that will not be removed when compiling release.
Trace macros that provide messages with source code link, run-time callstack information, and function prototype information with parameter values:
Extended Trace: Trace macros for Win32
I just use something like this (from memory, not tested at all...)
#define TRACE(msg) {\
std::ostringstream ss; \
ss << msg << "\n"; \
OutputDebugString(msg.str()); \
}
And then I can write things like :-
TRACE("MyClass::MyFunction returned " << value << " with data=" << some.data);
You can wrap that in some #ifdefs to remove it in release builds easily enough.
I found that using the _RPT() macro will also work with a C source file in Visual Studio 2005. This article Debugging with Visual Studio 2005/2008: Logging and Tracing provides an overview of TRACE, _RPT, and other logging type macros.
I generate a line for a log file called the ASSRTLOG which contains logs and when writing the log to the file, I also do the following source code line:
_RPT1(_CRT_WARN, "ASSRTLOG: %s", szLog1);
This line puts the same log that is going into the log file into the output window of the Visual Studio 2005 IDE.
You might be interested in the mechanics behind the approach we are using for logging. We have a function PifLogAbort() which accepts a series of arguments that are then used to generate a log. These arguments include the name of the file where the log is being generated along with the line number. The macro looks like this:
#define NHPOS_ASSERT_TEXT(x, txt) if (!(x)) { PifLogAbort( (UCHAR *) #x , (UCHAR *) __FILE__ , (UCHAR *) txt , __LINE__ );}
and the function prototype for PifLogAbort() look like this:
PifLogNoAbort(UCHAR *lpCondition, UCHAR *lpFilename, UCHAR *lpFunctionname, ULONG ulLineNo)
and to use the macro we will insert a line like this:
NHPOS_ASSERT_TEXT(sBRetCode >= 0, "CliEtkTimeIn(): EtkTimeIn() returned error");
What this macro will do is that if the return code is less than 0 (the assertion fails), a log will be generated with the provided text. The log includes the condition that generated the log along with file name and line number.
The function PifLogAbort() generates logs with a specified length and treats the output file as a circular buffer. The logs have a time and date stamp as well.
In those cases where we want to generate the descriptive text dynamically at run time, perhaps to provide the actual error code value, we use the sprintf() function with a buffer as in the following code sequence:
if (sErrorSave != STUB_BM_DOWN) {
char xBuff[128];
sprintf(xBuff, "CstSendBMasterFH: CstComReadStatus() - 0x%x, sError = %d", usCstComReadStatus, CliMsg.sError);
NHPOS_ASSERT_TEXT((sErrorSave == STUB_BM_DOWN), xBuff);
}
If we want the logs to not be generated, all we need to do is to go to the single header file where the macro is defined and define it to be nothing then recompile. However we have found that these logs can be very valuable when investigating field issues and are especially useful during integration testing.
Windows Events are a potential replacement for TRACE macros, depending on your particular scenario. The code gets compiled into both Debug and Release configurations. Event tracing can then be dynamically enabled and disabled, displayed in real-time, or dumped on a client's machine for later diagnosis. The traces can be correlated with trace information gathered from other parts of the OS as well.
If you merely need to dump information whenever code reaches certain checkpoints, together with variable content, stack traces, or caller names, Visual Studio's Tracepoints are a non-intrusive option to do so.