Hi
Suppose i have a LPSTR variable. How do i free the memory after using the variable. Is it
LPSTR szFileName = GetSBCSBuffer(sFilePath); // sFilePath is a CString
delete szFileName;
OR
delete []szFileName;
Kindly advise
views:
271answers:
2
+1
A:
If memory was allocated using new char[SIZE] then it needs to be freed using delete [].
elder_george
2009-11-06 15:36:05
i dont explicitly allocate all i do is written in that code where getsbcsbuffer() function accepts a string and returns a char * something like this int len = WideCharToMultiByte(CP_ACP, 0, str, -1, 0, 0, 0, 0); // allocate the buffer to hold the converted string LPSTR result = new char[len]; // do the conversion WideCharToMultiByte(CP_ACP, 0, str, -1, result, len, 0, 0); return result;
ckv
2009-11-06 15:56:44
+1
A:
You can't answer that question without knowing the specifics of GetSBCSBuffer. Hopefully whoever wrote the function left you with code and/or documentation so you can see where the string comes from. It might be that neither of your alternatives is correct. The author of GetSBCSBuffer might have used a different memory allocator or returned a pointer to a location internal to sFilePath. In the last case it would be very bad to call any deallocator.
I just noticed you answered the question yourself in your comment to elder_george's answer. The implementation used new[] so you need to delete[].
J. Loomis
2009-11-06 16:14:08
int len = WideCharToMultiByte(CP_ACP, 0, str, -1, 0, 0, 0, 0); // allocate the buffer to hold the converted string LPSTR result = new char[len]; // do the conversion WideCharToMultiByte(CP_ACP, 0, str, -1, result, len, 0, 0); return result;This is what is written in getsbcsbuffer.
ckv
2009-11-06 16:20:02
Sorry I put the answer in the original text because I don't know how to hyperlink in a comment (new at this). You just posted that result is allocated using new char[len] so you must free it by using delete[] szFileName. Always match new with delete and new[] with delete[].
J. Loomis
2009-11-06 16:24:08