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From: Z.K. on 20 Apr 2008 17:09 I was trying to convert the sprintf statement to sprintf_s, but though it compiles, it gives me an exception everytime when it reaches the sprintf_s statement and I am not really sure why. My knowledge of unicode and these new functions in VS 2005 are still new to me though I thought this would work since the only difference was a size requirement. const int BUFFSIZE = 128; char buffer2[BUFFSIZE]; lpstrEditcmd = &buffer2[0]; //sprintf(lpstrEditcmd,"%s\\edit.com",lpstrSysDir); sprintf_s(lpstrEditcmd,sizeof(lpstrEditcmd),"%s\\edit.com",lpstrSysDir); Of course if I just arbitrarily put in a size such as 128, then it gets passed that statement. I have used this same code in Visual 2003 without the modifications and it worked fine. Z.K.
From: Giovanni Dicanio on 20 Apr 2008 17:37 "Z.K." <nospam(a)nospam.net> ha scritto nel messaggio news:eNJfRsyoIHA.3976(a)TK2MSFTNGP03.phx.gbl... >I was trying to convert the sprintf statement to sprintf_s, but though it >compiles, it gives me an exception everytime when it reaches the sprintf_s >statement and I am not really sure why. Could you please be more specific about the "exception"? Is it a C++ run-time exception? Or it is a compile-time error? > My knowledge of unicode and these new functions in VS 2005 are still new > to me though I thought this would work since the only difference was a > size requirement. > const int BUFFSIZE = 128; > > char buffer2[BUFFSIZE]; To code Unicode aware, you should use TCHAR and not char: TCHAR buffer2[ BUFFSIZE ]; Now BUFFSIZE is the count of TCHAR's, which translates to the count of char's (bytes) in ANSI/MBCS builds, or to the count of wchar_t's (2 bytes per wchar_t) in Unicode builds. > lpstrEditcmd = &buffer2[0]; lpstrEditcmd should be TCHAR*. > //sprintf(lpstrEditcmd,"%s\\edit.com",lpstrSysDir); > sprintf_s(lpstrEditcmd,sizeof(lpstrEditcmd),"%s\\edit.com",lpstrSysDir); You should use _stprintf_s, which is the Unicode-aware version of sprintf_s. http://msdn2.microsoft.com/en-us/library/ce3zzk1k(VS.80).aspx Moreover, please pay attention to 2nd parameter of _stprintf_s: you need the size of the buffer (in TCHAR) as 2nd parameter, but if lpstrEditcmd is a TCHAR* (i.e.: just a pointer), your code sizeof(lpstrEditcmd) is just a size of a *pointer* (= 4 bytes on 32 bits architectures). If you want to write something to a buffer - call it 'Dest' - being Unicode aware, you should use something like this: <code> // Destination string buffer (statically defined on the stack) TCHAR Dest[ 500 ]; // Format string to that buffer (Unicode aware) _stprintf_s( Dest, // Destination buffer _countof( Dest ), // Count of TCHAR's in buffer _T("%s\\edit.com"), // Format string lpstrSysDir // I assume it is a TCHAR* ); </code> There are also functions like StringCbPrintf or StringCchPrintf for that purpose. StringCbPrintf: http://msdn2.microsoft.com/en-us/library/ms647510(VS.85).aspx StringCchPrintf: http://msdn2.microsoft.com/en-us/library/ms647541(VS.85).aspx However, IMHO the best thing to do is to use a robust string class, like CString. CString defines operators like + and +=, that help in concatenating strings. And there is also the CString::Format method for printf-like formatting. I prefer using robust string classes instead of programming using raw C-style arrays of TCHARs... > Of course if I just arbitrarily put in a size such as 128, then it gets > passed that statement. I have used this same code in Visual 2003 without > the modifications and it worked fine. Maybe in VS2003 the default compilation model was MBCS/ANSI, but in VS2005/2008 the default model is Unicode, so you are running into problems due to this new default character model. If you program Unicode-aware, using TCHAR's, etc. you should have no problems. HTH, Giovanni
From: Norman Bullen on 20 Apr 2008 17:55 Z.K. wrote: > I was trying to convert the sprintf statement to sprintf_s, but though > it compiles, it gives me an exception everytime when it reaches the > sprintf_s statement and I am not really sure why. My knowledge of > unicode and these new functions in VS 2005 are still new to me though I > thought this would work since the only difference was a size requirement. > > > const int BUFFSIZE = 128; > > char buffer2[BUFFSIZE]; > > lpstrEditcmd = &buffer2[0]; > > //sprintf(lpstrEditcmd,"%s\\edit.com",lpstrSysDir); > sprintf_s(lpstrEditcmd,sizeof(lpstrEditcmd),"%s\\edit.com",lpstrSysDir); > > > > Of course if I just arbitrarily put in a size such as 128, then it gets > passed that statement. I have used this same code in Visual 2003 > without the modifications and it worked fine. > > > Z.K. Your problem is that you're passing the size of a pointer instead of the size of the buffer. I would remove the pointer entirely and rewrite the statement as sprintf_s(buffer2, sizeof buffer2, "%s\\edit.com", ... ); If you may need to upgrade this code to Unicode in the future, use #include <TCHAR.H> const int BUFFSIZE = 128; TCHAR buffer2[BUFFSIZE]; _stprintf_s(buffer2, _countof(buffer2), _T("s\\edit.com"), ... (; -- Norm To reply, change domain to an adult feline.
From: David Wilkinson on 20 Apr 2008 17:42 Z.K. wrote: > I was trying to convert the sprintf statement to sprintf_s, but though > it compiles, it gives me an exception everytime when it reaches the > sprintf_s statement and I am not really sure why. My knowledge of > unicode and these new functions in VS 2005 are still new to me though I > thought this would work since the only difference was a size requirement. > > > const int BUFFSIZE = 128; > > char buffer2[BUFFSIZE]; > > lpstrEditcmd = &buffer2[0]; > > //sprintf(lpstrEditcmd,"%s\\edit.com",lpstrSysDir); > sprintf_s(lpstrEditcmd,sizeof(lpstrEditcmd),"%s\\edit.com",lpstrSysDir); > > > > Of course if I just arbitrarily put in a size such as 128, then it gets > passed that statement. I have used this same code in Visual 2003 > without the modifications and it worked fine. Z.K. Your question has nothing to do with Unicode (for Unicode strings you would use swprintf_s). You do not give the type of lpstrEditcmd, but its size is likely the size of a pointer (4 or 8 bytes). But why do you need it? Why don't you just do const int BUFFSIZE = 128; char buffer2[BUFFSIZE]; sprintf_s(buffer2, BUFFSIZE, "%s\\edit.com",lpstrSysDir); ? -- David Wilkinson Visual C++ MVP
From: Z.K. on 20 Apr 2008 19:29
Z.K. wrote: > I was trying to convert the sprintf statement to sprintf_s, but though > it compiles, it gives me an exception everytime when it reaches the > sprintf_s statement and I am not really sure why. My knowledge of > unicode and these new functions in VS 2005 are still new to me though I > thought this would work since the only difference was a size requirement. > > > const int BUFFSIZE = 128; > > char buffer2[BUFFSIZE]; > > lpstrEditcmd = &buffer2[0]; > > //sprintf(lpstrEditcmd,"%s\\edit.com",lpstrSysDir); > sprintf_s(lpstrEditcmd,sizeof(lpstrEditcmd),"%s\\edit.com",lpstrSysDir); > > > > Of course if I just arbitrarily put in a size such as 128, then it gets > passed that statement. I have used this same code in Visual 2003 > without the modifications and it worked fine. > > > Z.K. Okay, thanks a lot everyone; you've answered several questions that I had. I will give it another try. Z.K. |