C / C++ / MFC

Re: windbg to the rescue!

4-Sep-06 23:35

No. When you create a mutex you can give it a unique name. So you need a different name for each pair of threads. Because only 2 threads will share the same mutex name, they will only ever be able to lock each other out. So, for example, you have 10 threads with 5 blocks of memory, you should create 5 mutex names.

user.dmp issue

Rob Caldecott4-Sep-06 6:40

Rob Caldecott

4-Sep-06 6:40

A customer of mine has sent me a user.dmp file generated when a debug version of an application of mine crashes. The application was compiled with VS2005. Now, I thought I could open and then run .dmp files in Visual Studio, but when I run this file I get the following error:

Debugging older format crashdumps is not supported

Anyone know how I can extract some useful information from this .dmp file? The call stack would be useful and it would at least give me some idea where the problem occurs!

Thanks in advance.

The Rob Blog
Google Talk: robert.caldecott

windbg to the rescue!

Rob Caldecott4-Sep-06 6:58

Rob Caldecott

4-Sep-06 6:58

Downloaded windbg and this allows me to open the file...

Waldermort4-Sep-06 7:03

replacing a string with a sub-string

4-Sep-06 7:03

lmao, I was just scratching my brains trying to remember the name of that program so I could tell you to try it.

jon-804-Sep-06 6:29

Re: replacing a string with a sub-string

4-Sep-06 6:29

I would like to loop through a vector<string> type and remove the contents of strSearch from
all the lines within Sentences.

CSentences.h
...
std::vector <std::string> Sentences; //list of sentences.
...

The following function returns the number of occurrences of strSearch within sentence.

CSentences.cpp

unsigned int CSentenceList::searchInSentence(const string sentence, char* strSearch)
{
char buffer[MAX_SENTENCE_LENGTH + 1] = {0};

const char* l_strSentence = sentence.c_str();

memcpy(buffer, l_strSentence, MAX_SENTENCE_LENGTH);

char* strToken = 0;
unsigned long iWordCount = 0;
strToken = strstr(buffer, strSearch);

while (strToken !=NULL)
{
if (strlen(strToken) > 0)
{ // For each line within Sentences
// remove strSearch

iCount++;
strToken += strlen(strSearch);
}

strToken = strstr(strToken, strSearch);

}
return iCount;
}

Jon

Graham Shanks4-Sep-06 12:28

Graham Shanks

4-Sep-06 12:28

The following function removes all occurances of strSearch in sentence:

void StringRemove(std::string& sentence, const char * const strSearch)
{
  size_t len = strlen(strSearch);
  std::string::size_type i = sentence.find(strSearch);
  while(i != std::string::npos)
  {
    sentence.erase(i, len);
    i = sentence.find(strSearch, i);
  }
}

If, as the title of your post suggests you actually want to replace a substring use the following:

void StringReplace(std::string&       sentence, 
                   const char * const strSearch,
                   const char* const  strNew)
{
  size_t len = strlen(strSearch);
  size_t newLen = strlen(strNew);
  std::string::size_type i = sentence.find(strSearch);
  while(i != std::string::npos)
  {
    sentence.replace(i, len, strNew, newLen);
    i = sentence.find(strSearch, i + newLen);
  }
}

To replace all occurances in the vector use:

std::vector<std::string>::iterator i;
for(i = sentences.begin(); i != sentences.end();++i)
  StringReplace(*i, "foo", "bar");

BTW a more succinct version of your count occurances in string function is

unsigned int StringCount(const std::string& sentence, 
                         const char* const  strSearch)
{
  unsigned int count = 0;
  size_t len = strlen(strSearch);
  std::string::size_type i = sentence.find(strSearch);
  while(i != std::string::npos)
  {
    i = sentence.find(strSearch, i + len);
    ++count;
  }
  return count;
}

Graham

My signature is not black, just a very, very dark blue

reduce the size of an array of chars....

jon-804-Sep-06 6:22

4-Sep-06 6:22

This function REMOVES sub-string of strText starting at iStart and resuming at iStart + iNoOfChars:

string CSentenceList::subString(char* strText, int iStart, int iNoOfChars)
{
int iLength = strlen(strText);
char l_Substring[MAX_SENTENCE_LENGTH];

// copy character by character till iStart
for (int iFirstCount = 0; iFirstCount < iStart; iFirstCount++)
{l_Substring[iFirstCount] = strText[iFirstCount];}

// copy from iContinue till the end of the text
int iContinue = iStart + iNoOfChars;
for (int iSecondCount = iContinue; iSecondCount < iLength; iSecondCount++, iFirstCount++)
{l_Substring[iFirstCount] = strText[iSecondCount];}

return (string) l_Substring;
}

However, the string returned is terminated by a series of unreadable characters. For example, substring ("joe123joe",3,3) should return "joejoe", but it returns:
joejoe╠╠╠╠╠╠╠╠... // up to the value of MAX_SENTENCE_LENGTH (1000)

I have tried using dynamic arrays of chars but I had trouble converting them to std::string type.

Jon

Waldermort4-Sep-06 6:25

4-Sep-06 6:25

Add a NULL terminator to the end of the string. Or better still, call memset() for l_Substring and zero the memory.

memset(l_Substring,0,MAX_SENTENCE_LENGTH);

jon-804-Sep-06 6:32

4-Sep-06 6:32

I think the above line zero's the memory for l_Substring. I would like to remove what has not already been 'filled' within the function.

How do I add a NULL terminator btw?

Jon

Waldermort4-Sep-06 6:43

4-Sep-06 6:43

jon_80 wrote:
I think the above line zero's the memory for l_Substring. I would like to remove what has not already been 'filled' within the function.

When you memset with '0', you are filling the array with NULL terminators, so after you add your characters one by one there will be a NULL at the end.

jon_80 wrote:
How do I add a NULL terminator btw?

After you have added the last character, increase the pointer and make it = '0' instead of adding a character.

jon-804-Sep-06 8:11

4-Sep-06 8:11

string CSentenceList::removeSubstring(char* strText, int iStart, int iNoOfChars)
The NULL is not started at the end of the string though...

{
int iLength = strlen(strText);
char l_Substring[MAX_SENTENCE_LENGTH];

// copy character by character till iStart
for (int iFirstCount = 0; iFirstCount < iStart; iFirstCount++)
{l_Substring[iFirstCount] = strText[iFirstCount];}

// copy from iContinue till the end of the text
int iContinue = iStart + iNoOfChars;
for (int iSecondCount = iContinue; iSecondCount < iLength; iSecondCount++, iFirstCount++)
{l_Substring[iFirstCount] = strText[iSecondCount];}

memset(l_Substring,0,MAX_SENTENCE_LENGTH); //resets l_Substring to ""
return (string) l_Substring;
}

Jon

Control handles

Oliver1234-Sep-06 6:17

Oliver123

4-Sep-06 6:17

I am finding references to control handles in VC++, but haven't yet found a definition. What is the handle? When I create an edit box, it returns a label of IDC_EDIT1, IDC_EDIT2, etc. Is this the handle? Is the handle the variable m_edit1 that I assign to he control?

Re: Control handles

Waldermort4-Sep-06 6:26

Re: scanning until the EOF

4-Sep-06 6:26

The handle for a control is commonly called the HWND <-- 'H' means Handle

Re: Control handles

gregdolley4-Sep-06 22:21

gregdolley

4-Sep-06 22:21

A handle (such as HWND or HANDLE) is simply typedef'ed to a long. It is a unique number assigned by the operating system to every window. When you create a window through the Win32 API, a handle is returned (HWND). Whenever you want to do something to that window you pass the HWND value to whatever Win32 function you're calling. Since MFC is basically a huge wrapper around the whole Win32 API, handles work the same way in MFC.

Your IDC_EDIT1, IDC_EDIT2, etc constants refer to the resource ID of a particular control. It is not the same as the handle. The resource ID is simply a number that the compiler uses when making resource files.

The control MFC classes (such as CEdit, CComboBox, etc.) all have a method called GetSafeHwnd() and a member called m_hWnd. Whenever you need a handle (HWND) of your control, just call GetSafeHwnd(). Or you can just grab the value of m_hWnd (it is public).

-Greg Dolley

Re: Control handles

Hamid_RT11-Sep-06 9:52

Hamid_RT

11-Sep-06 9:52

We have many handle in VC for example HWND window/HMENU menu /HDC Context_Device and... when you declare a variable for editbox this handle in Hierarchy Chart is CObject->CCmdTarget->CWnd->CEdit

WhiteSky

scanning until the EOF

Desmo164-Sep-06 6:15

Desmo16

4-Sep-06 6:15

Hi all,
I have the following code:

// CODE STARTS HERE //
int i,j;
std::fstream f_load;
char appoggio[20]; // carica il nan oppure il valore numerico
CString percorso;
CFileDialog fd(TRUE, NULL, percorso, OFN_FILEMUSTEXIST | OFN_HIDEREADONLY);
fd.m_pOFN->lpstrTitle = "Carica file di osservazioni";
if (fd.DoModal() == IDOK)
{
percorso = fd.GetPathName();
UpdateData(false);
f_load.open(percorso,std::ios::in);
int contatore = 0;
do{
f_load>>appoggio;
contatore++;
}
while(f_load!=EOF);
}

// CODE ENDS HERE //

but there's something wrong in the while condition.
Which is the right while condition to scan the file until its end ?
Thanx in advance,
Desmo16.

Waldermort4-Sep-06 6:30

Re: scanning until the EOF

4-Sep-06 6:30

In your loop, you are checking if the EOF has been reached at the end of the loop, but the pointer has already been increased causing your code not to go through the loop for the final time. You should test before entering the loop, ie

while (f_load != EOF)<br />
{<br />
   // do your loop<br />
}

Desmo164-Sep-06 6:40

Desmo16

4-Sep-06 6:40

I don't think it's that the matter,
because the compiler tells me it cannot convert
an int (the EOF) into a std::fstream (the f_load)

Re: scanning until the EOF

Waldermort4-Sep-06 6:49