C / C++ / MFC

Josh Gray wrote:

There is only one stack, you can consider it a global stack I guess

#include <string>

using namespace std;

string& goo()
{
	string myString("George is cool 111111111111111111111 11111111111111111111111111111111111");
	return myString;
}

void foo()
{
	string& str = goo();
}

George_George wrote:

1. In goo, it allocates a string, small. In your point, it should be on the stack on function goo, right?

George_George wrote:

Is it safe?

char *goo1( void )
{
    char *s = new char[5];
    return s;
}
 
char *goo2( void )
{
    char s[5];
    return s;
}
 
string s1 = goo1(); // this is fine since goo1() allocated from heap
string s2 = goo2(); // the local variable in goo2() will be 
                    // invalid once the function goes out of scope

markt wrote:

scott meyers was worth buying

void CMyAsyncSocket::OnReceive(int nErrorCode)
{
    <font color="Green">// loop receiving datagrams until there's no more to receive this FD_READ cycle</font>
    while (1)
    {
        int BytesIn = ReceiveFrom(Buff, BuffSize, SenderAdd, SenderPrt);

        if (0 == BytesIn)
        {
            <font color="Green">// connection closed (TCP sockets only - should never get here with UDP)</font>
            return;
        }
        else if (SOCKET_ERROR == BytesIn)
        {
            DWORD errcode = GetLastError();
            if (WSAEWOULDBLOCK == errcode)
            {
                <font color="Green">// no more datagrams available to receive - just return</font>
                return;
            }
            else
            {
                <font color="Green">// some bad error occurred - errcode is the error code</font>
                return;
            }
        }

        <font color="Green">// Datagram successfully received!</font>
        PacketsRcvd++;

        <font color="Green">// this does nothing
        //CAsyncSocket::OnReceive(nErrorCode);</font>
    }
}

Mark Salsbery
Microsoft MVP - Visual C++