CopyFile to a custom location, with string conversion problem - c++

Question

I am trying to make this application copy itself to appdata, which requires the USERNAME, which I already have.
But, for some reason, the file doesn't copy to this place. I tried a lot of string conversion to char, but none of them worked for the strcat() and CopyFile() functions.
Here is the code:
char user[UNLEN + 1];
char Original[MAX_PATH];
DWORD User_len = UNLEN + 1;
GetUserName(user, & User_len);
std::string Path("C:\\Users\\");
Path += user;
Path += ("\\AppData\\Other Stuff");
GetModuleFileName(NULL, OriginalFile, sizeof(OriginalFile))
char *PathChr = new char(Path.length() + 1); // Might be wrong but continue...
strcat(PathChr, "something.exe");
CopyFile(OriginalFile, PathChr, NULL);
The question is now solved!

Answer 1

You are not allocating enough memory for PathChr. You are allocating only 1 char, not Path.length() number of chars. You need to use [] instead of () when calling new, eg:
char *PathChr = new char[Path.length() + 1];
...
delete[] PathChr;
Alternatively, forget using new[], just use the std::string you already created, eg:
std::string Path = "C:\\Users\\";
Path += user;
Path += "\\AppData\\Other Stuff\\";
Path += "something.exe";
...
CopyFileA(OriginalFile, Path.c_str(), NULL);
But, since you already know the maximum array length up front (UNLEN + 43), you don't need a dynamically allocated string at all, a fixed array will suffice:
char user[UNLEN + 1];
char Path[UNLEN + 46];
char Original[MAX_PATH];
DWORD User_len = UNLEN + 1;
GetUserName(user, &User_len);
strcpy(Path, "C:\\Users\\");
strcat(Path, user);
strcat(Path, "\\AppData\\Other Stuff\\something.exe");
GetModuleFileName(NULL, OriginalFile, sizeof(OriginalFile));
CopyFileA(OriginalFile, Path, NULL);
That being said, the location of the AppData folder is user-customizable, so do not hard-code it. The correct way to get the actual AppData path is to use SHGetFolderPath() with CSIDL_(LOCAL_)APPDATA, or SHGetKnownFolderPath() with FOLDERID_(Roaming|Local)AppData, eg:
char AppData[MAX_PATH];
char Path[MAX_PATH];
char Original[MAX_PATH];
SHGetFolderPathA(NULL, CSIDL_APPDATA, NULL, SHGFP_TYPE_CURRENT, AppData);
LPSTR pDest = PathCombineA(Path, AppData, "Other Stuff\\something.exe");
GetModuleFileName(NULL, OriginalFile, sizeof(OriginalFile));
CopyFileA(OriginalFile, pDest, NULL);