Re: Memory leaks help with char*

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Jeremy Chapman wrote:

I've written the following code. After not having written a single line of c++ for about 3 or more years, I'm feeling a little uneasy about it.
First of all, I'm sure I've got some memory leaks here. Also, I get an error when I try to delete my char* variables. I've tried delete and delete[].
Can someone verify I'm doing this right?

 //Get appdirectory
 char* pszFileName = new char[1024];
 pszFileName[1024] = 0;

 char* pszCommand = new char[1024];
 pszCommand[1024] = 0;

 char* pszArgs = new char[1024];
 pszArgs[1024] = 0;

 DWORD nSize = 1024;
 DWORD iRetVal = GetModuleFileName(NULL,pszFileName,nSize);

 //Load config file for this app
 pszFileName = strcat(pszFileName,".config");
 ifstream pfile(pszFileName, ios::in|ios::binary);

 if (pfile)
 {
    //first line in app is command to run
  pfile.getline(pszCommand, 1024);
    //second line is parameters
  pfile.getline(pszArgs, 1024);

  pfile.close();
  //delete pfile;
 }

 ShellExecute(NULL, pszCommand, pszArgs, NULL, NULL, SW_SHOWNORMAL);

return 0; 



Jeremy:

In addition to Barry's comment (you don't need that line anyway), never use "new" unless you have to. Just do

char pszFileName[_MAX_PATH+10];

This leaves room for the ".config" that you want to add.

You could do also

char pszCommand[1024];
char pszArgs[1024];

but you would do better to do

std::string command;
std::string args;

std::getline(pFile, command);
std::getline(pFile, args);

ShellExecute(NULL, command.c_str(), args.c_str(), NULL, NULL, SW_SHOWNORMAL);

Are you sure that this code is going to work? GetModuleFileName() gets the full path of the executable, which probably has a .exe extension.

Your code will certainly leak as written. Every time you use new, there must be a corresponding delete or delete []. Here you need delete []. Don't know why this did not work for you. But you don't need those new's anyway.

HTH,

David Wilkinson


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