Thread: strange linked list problem

Normaly I would post this in the C++ board, but I think the problem is windows related.

I have class witch can add nodes and brows through a linked list.
the function that adds the node looks like this:

Code:

bool CMP3LIST::AddToList(int length,char title[MAX_PATH],char filepath[MAX_PATH])
{	
	if (firsttime)
	{
		nieuw=(MP3STRUCTLIST *)malloc(sizeof(MP3STRUCTLIST));		
		eerst=deze=nieuw;
		firsttime = false;
	}
	else
	{						
		deze->nextrecord=(MP3STRUCTLIST *)malloc(sizeof(MP3STRUCTLIST));  
		deze=deze->nextrecord;			
		deze->nextrecord=nieuw;	
	}
	total_records++;
	deze->number=total_records;
	current_record++;
	deze->length=length;
	strcpy(deze->name,title);
	strcpy(deze->path,filepath);

	return true;
}

some words are dutch, I'll translate to clearefy (sp?)
nieuw=new
deze=this
eerst=first

so when I want to add a nod, I call the function like this:
playlist.AddToList(000,lpofn.lpstrFile,lpofn.lpstr File);
lpofn is of the type OPENFILENAME
and lpofn.lpstrFile gets filled in by the GetOpenFileName function from the WIN32 API

but after the malloc, the value of lpofn.lpstrFile changes. I don't see how this is possible? does windows override a piece of memory that holds the OPENFILENAME data? and strangly, there is just one letter that changes in the filename
example: c:\My Documents\... changes to c:\My DoTuments\...

How is this possible????
is there some underlying memory bug somewhere that I'm not aware of.

I corrected the problem by adding a strcpy before the addtolist function, like this:

Code:

strcpy(buffer,lpofn.lpstrFile);
playlist.AddToList(000,buffer,buffer);

it works, but it doesn't give me an explination why this happens.
and the lpofn.lpstrFile still changes and it isn't even part of the class it is a global variable.

anyone has an idea about this, why this happens?

thx

--Maes

BTW, if my function to add nodes contains bugs, or there are better ways to do it, let my know