Logging

Detailed Description

These functions provide a variety of logging functions.

The functions use (implicitly) the currently active log target, so their descriptions here may not apply if the log target is not the standard one (installed by wxWidgets in the beginning of the program).

Related Overviews: Logging Overview

Related class group: Logging

Macros
#define	WXTRACE(format,...)
#define	WXTRACELEVEL(level, format,...)

Functions
void	wxSafeShowMessage (const wxString &title, const wxString &text)
	This function shows a message to the user in a safe way and should be safe to call even before the application has been initialized or if it is currently in some other strange state (for example, about to crash). More...
unsigned long	wxSysErrorCode ()
	Returns the error code from the last system call. More...
const wxChar *	wxSysErrorMsg (unsigned long errCode=0)
	Returns the error message corresponding to the given system error code. More...
void	wxLogGeneric (wxLogLevel level, const char *formatString,...)
	Logs a message with the given wxLogLevel. More...
void	wxVLogGeneric (wxLogLevel level, const char *formatString, va_list argPtr)
void	wxLogMessage (const char *formatString,...)
	For all normal, informational messages. More...
void	wxVLogMessage (const char *formatString, va_list argPtr)
void	wxLogVerbose (const char *formatString,...)
	For verbose output. More...
void	wxVLogVerbose (const char *formatString, va_list argPtr)
void	wxLogWarning (const char *formatString,...)
	For warnings - they are also normally shown to the user, but don't interrupt the program work. More...
void	wxVLogWarning (const char *formatString, va_list argPtr)
void	wxLogFatalError (const char *formatString,...)
	Like wxLogError(), but also terminates the program with the exit code 3. More...
void	wxVLogFatalError (const char *formatString, va_list argPtr)
void	wxLogError (const char *formatString,...)
	The functions to use for error messages, i.e. More...
void	wxVLogError (const char *formatString, va_list argPtr)
void	wxLogTrace (const char *mask, const char *formatString,...)
	Log a message at wxLOG_Trace log level (see wxLogLevelValues enum). More...
void	wxVLogTrace (const char *mask, const char *formatString, va_list argPtr)
void	wxLogTrace (wxTraceMask mask, const char *formatString,...)
	Like wxLogDebug(), trace functions only do something in debug builds and expand to nothing in the release one. More...
void	wxVLogTrace (wxTraceMask mask, const char *formatString, va_list argPtr)
void	wxLogDebug (const char *formatString,...)
	The right functions for debug output. More...
void	wxVLogDebug (const char *formatString, va_list argPtr)
void	wxLogStatus (wxFrame *frame, const char *formatString,...)
	Messages logged by this function will appear in the statusbar of the frame or of the top level application window by default (i.e. More...
void	wxVLogStatus (wxFrame *frame, const char *formatString, va_list argPtr)
void	wxLogStatus (const char *formatString,...)
void	wxVLogStatus (const char *formatString, va_list argPtr)
void	wxLogSysError (const char *formatString,...)
	Mostly used by wxWidgets itself, but might be handy for logging errors after system call (API function) failure. More...
void	wxVLogSysError (const char *formatString, va_list argPtr)
void	wxTrace (const wxString &format,...)
void	wxTraceLevel (int level, const wxString &format,...)

Macro Definition Documentation

#define WXTRACE	(		format,
			...
	)

Deprecated:

Use one of the wxLogTrace() functions or one of the wxVLogTrace() functions instead.

Calls wxTrace() with printf-style variable argument syntax. Output is directed to the current output stream (see wxDebugContext).

Include file:

#include <wx/memory.h> 

#define WXTRACELEVEL	(		level,
			format,
			...
	)

Deprecated:

Use one of the wxLogTrace() functions or one of the wxVLogTrace() functions instead.

Calls wxTraceLevel with printf-style variable argument syntax. Output is directed to the current output stream (see wxDebugContext). The first argument should be the level at which this information is appropriate. It will only be output if the level returned by wxDebugContext::GetLevel is equal to or greater than this value.

Include file:

#include <wx/memory.h> 

Function Documentation

void wxLogDebug	(	const char *	formatString,
			...
	)

The right functions for debug output.

They only do something in debug mode (when the preprocessor symbol WXDEBUG is defined) and expand to nothing in release mode (otherwise).

Include file:

#include <wx/log.h> 

void wxLogError	(	const char *	formatString,
			...
	)

The functions to use for error messages, i.e.

the messages that must be shown to the user. The default processing is to pop up a message box to inform the user about it.

Include file:

#include <wx/log.h> 

void wxLogFatalError	(	const char *	formatString,
			...
	)

Like wxLogError(), but also terminates the program with the exit code 3.

Using abort() standard function also terminates the program with this exit code.

Include file:

#include <wx/log.h> 

void wxLogGeneric	(	wxLogLevel	level,
		const char *	formatString,
			...
	)

Logs a message with the given wxLogLevel.

E.g. using wxLOG_Message as first argument, this function behaves like wxLogMessage().

Include file:

#include <wx/log.h> 

void wxLogMessage	(	const char *	formatString,
			...
	)

For all normal, informational messages.

They also appear in a message box by default (but it can be changed).

Include file:

#include <wx/log.h> 

void wxLogStatus	(	wxFrame *	frame,
		const char *	formatString,
			...
	)

Messages logged by this function will appear in the statusbar of the frame or of the top level application window by default (i.e.

when using the second version of the functions).

If the target frame doesn't have a statusbar, the message will be lost.

Include file:

#include <wx/log.h> 

void wxLogStatus	(	const char *	formatString,
			...
	)

void wxLogSysError	(	const char *	formatString,
			...
	)

Mostly used by wxWidgets itself, but might be handy for logging errors after system call (API function) failure.

It logs the specified message text as well as the last system error code (errno or GetLastError() depending on the platform) and the corresponding error message. The second form of this function takes the error code explicitly as the first argument.

See also

wxSysErrorCode(), wxSysErrorMsg()

Include file:

#include <wx/log.h> 

void wxLogTrace	(	const char *	mask,
		const char *	formatString,
			...
	)

Log a message at wxLOG_Trace log level (see wxLogLevelValues enum).

Notice that the use of trace masks is not recommended any more as setting the log components (please see Log Messages Selection) provides a way to do the same thing for log messages of any level, and not just the tracing ones.

Like wxLogDebug(), trace functions only do something in debug builds and expand to nothing in the release one. The reason for making it a separate function is that usually there are a lot of trace messages, so it might make sense to separate them from other debug messages.

Trace messages can be separated into different categories; these functions in facts only log the message if the given mask is currently enabled in wxLog. This lets you selectively trace only some operations and not others by enabling the desired trace masks with wxLog::AddTraceMask() or by setting the WXTRACE environment variable.

The predefined string trace masks used by wxWidgets are:

wxTRACE_MemAlloc	Trace memory allocation (new/delete)
wxTRACE_Messages	Trace window messages/X callbacks
wxTRACE_ResAlloc	Trace GDI resource allocation
wxTRACE_RefCount	Trace various ref counting operations
wxTRACE_OleCalls	Trace OLE method calls (Win32 only)

Include file:

#include <wx/log.h> 

void wxLogTrace	(	wxTraceMask	mask,
		const char *	formatString,
			...
	)

Like wxLogDebug(), trace functions only do something in debug builds and expand to nothing in the release one.

The reason for making it a separate function is that usually there are a lot of trace messages, so it might make sense to separate them from other debug messages.

Deprecated:

This version of wxLogTrace() only logs the message if all the bits corresponding to the mask are set in the wxLog trace mask which can be set by calling wxLog::SetTraceMask(). This version is less flexible than wxLogTrace(const char*,const char*,...) because it doesn't allow defining the user trace masks easily. This is why it is deprecated in favour of using string trace masks.

The following bitmasks are defined for wxTraceMask:

wxTraceMemAlloc	Trace memory allocation (new/delete)
wxTraceMessages	Trace window messages/X callbacks
wxTraceResAlloc	Trace GDI resource allocation
wxTraceRefCount	Trace various ref counting operations
wxTraceOleCalls	Trace OLE method calls (Win32 only)

Include file:

#include <wx/log.h> 

void wxLogVerbose	(	const char *	formatString,
			...
	)

For verbose output.

Normally, it is suppressed, but might be activated if the user wishes to know more details about the program progress (another, but possibly confusing name for the same function could be wxLogInfo).

Include file:

#include <wx/log.h> 

void wxLogWarning	(	const char *	formatString,
			...
	)

For warnings - they are also normally shown to the user, but don't interrupt the program work.

Include file:

#include <wx/log.h> 

void wxSafeShowMessage	(	const wxString &	title,
		const wxString &	text
	)

This function shows a message to the user in a safe way and should be safe to call even before the application has been initialized or if it is currently in some other strange state (for example, about to crash).

Under Windows this function shows a message box using a native dialog instead of wxMessageBox() (which might be unsafe to call), elsewhere it simply prints the message to the standard output using the title as prefix.

Parameters

title	The title of the message box shown to the user or the prefix of the message string.
text	The text to show to the user.

See also

wxLogFatalError()

Include file:

#include <wx/log.h> 

unsigned long wxSysErrorCode

(

)

Returns the error code from the last system call.

This function uses errno on Unix platforms and GetLastError under Win32.

See also

wxSysErrorMsg(), wxLogSysError()

Include file:

#include <wx/log.h> 

const wxChar* wxSysErrorMsg

(

unsigned long

errCode = 0

)

Returns the error message corresponding to the given system error code.

If errCode is 0 (default), the last error code (as returned by wxSysErrorCode()) is used.

See also

wxSysErrorCode(), wxLogSysError()

Include file:

#include <wx/log.h> 

void wxTrace	(	const wxString &	format,
			...
	)

Deprecated:

Use one of the wxLogTrace() functions or one of the wxVLogTrace() functions instead.

Takes printf-style variable argument syntax. Output is directed to the current output stream (see wxDebugContext).

Include file:

#include <wx/memory.h> 

void wxTraceLevel	(	int	level,
		const wxString &	format,
			...
	)

Deprecated:

Use one of the wxLogTrace() functions or one of the wxVLogTrace() functions instead.

Takes printf() style variable argument syntax. Output is directed to the current output stream (see wxDebugContext). The first argument should be the level at which this information is appropriate. It will only be output if the level returned by wxDebugContext::GetLevel() is equal to or greater than this value.

Include file:

#include <wx/memory.h> 

void wxVLogDebug	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogError	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogFatalError	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogGeneric	(	wxLogLevel	level,
		const char *	formatString,
		va_list	argPtr
	)

void wxVLogMessage	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogStatus	(	wxFrame *	frame,
		const char *	formatString,
		va_list	argPtr
	)

void wxVLogStatus	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogSysError	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogTrace	(	const char *	mask,
		const char *	formatString,
		va_list	argPtr
	)

void wxVLogTrace	(	wxTraceMask	mask,
		const char *	formatString,
		va_list	argPtr
	)

void wxVLogVerbose	(	const char *	formatString,
		va_list	argPtr
	)

void wxVLogWarning	(	const char *	formatString,
		va_list	argPtr
	)