LIBCD.lib(crt0.obj) : error LNK2001: unresolved external symbol _main

[vonLandenhausen]

how to compile this?

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// MiniChat - Copyright (C) 2003 Skywing

#include <winsock2.h>
#include <windows.h>
#include <richedit.h>

// Visual C++-specific
#pragma intrinsic(memcmp, memcpy, memset, strcat, strcmp, strcpy, strlen)

#define MAKEIP(b4,b3,b2,b1) ((LPARAM)(((DWORD)(b1)<<24)+((DWORD)(b2)<<16)+((DWORD)(b3)<<8)+((DWORD)(b4))))
#define RENDIAN_WORD(W) ((HIBYTE(WORD(W)) >> 0) | (LOBYTE(WORD(W)) << 8))
#define DATA_SIZE 4096
#pragma comment( lib, "ws2_32.lib" )

int InitWinsock(void)
{
WSAData Data;

return WSAStartup(0x0202, &Data);
}

int Connect(SOCKET Sock)
{
SOCKADDR_IN Address;

Address.sin_addr.s_addr = MAKEIP(63,240,202,138);
//Address.sin_addr.s_addr = MAKEIP(211,233,0,76);
Address.sin_port = RENDIAN_WORD(6112);
Address.sin_family = AF_INET;

memset(Address.sin_zero, 0, sizeof(Address.sin_zero));

return connect(Sock, (PSOCKADDR)&Address, sizeof(Address));
}

void* Alloc(DWORD Size)
{
return HeapAlloc(GetProcessHeap(), HEAP_NO_SERIALIZE, Size);
}

void* AllocZ(DWORD Size)
{
return HeapAlloc(GetProcessHeap(), HEAP_NO_SERIALIZE | HEAP_ZERO_MEMORY, Size);
}

void Free(void* Memory)
{
HeapFree(GetProcessHeap(), HEAP_NO_SERIALIZE, Memory);
}

VOID WINAPI SendCompletion(DWORD dwErrorCode, DWORD dwNumberOfBytesTransferred,
  LPOVERLAPPED lpOverlapped)
{
Free(lpOverlapped->hEvent); // Data duplicated
Free(lpOverlapped);
}

void SendData(SOCKET Sock, const char* Data)
{
size_t Bytes = strlen(Data);

void* DuplicateData = Alloc(Bytes);
LPOVERLAPPED Overlapped = (LPOVERLAPPED)AllocZ(sizeof(OVERLAPPED));

memcpy(DuplicateData, Data, Bytes);
Overlapped->hEvent = DuplicateData;

WriteFileEx((HANDLE)Sock, DuplicateData, Bytes, Overlapped, &SendCompletion);
}

struct ReceiveOverlapped : public OVERLAPPED {
SOCKET Sock;
bool* Disconnect;
HWND OutWindow;
};

VOID WINAPI ReceiveCompletion(DWORD dwErrorCode, DWORD dwNumberOfBytesTransferred,
 ReceiveOverlapped* lpOverlapped)
{
if(!dwErrorCode && dwNumberOfBytesTransferred) {
LPBYTE Data = (LPBYTE)lpOverlapped->hEvent;
CHARRANGE Range = {-1, -1};

Data[dwNumberOfBytesTransferred] = '\0';

SendMessage(lpOverlapped->OutWindow, EM_EXSETSEL, 0, (LPARAM)&Range);
SendMessage(lpOverlapped->OutWindow, EM_REPLACESEL, FALSE, (LPARAM)Data);

ReadFileEx((HANDLE)lpOverlapped->Sock, Data, DATA_SIZE-1, lpOverlapped,
(LPOVERLAPPED_COMPLETION_ROUTINE)&ReceiveCompletion);
} else {
closesocket(lpOverlapped->Sock);
*lpOverlapped->Disconnect = true;
}
}

void RunMainLoop(HWND OutWindow, HWND InWindow)
{
SOCKET Sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

if(Sock == INVALID_SOCKET)
return;

bool Disconnect = false;

if(!Connect(Sock)) {
ShowWindow(OutWindow, SW_SHOW);
ShowWindow(InWindow, SW_SHOW);

BYTE Data[DATA_SIZE];
ReceiveOverlapped Overlapped; // This MUST NOT go out of scope while ReadFileEx is in progress
Overlapped.hEvent = Data;
Overlapped.Sock = Sock;
Overlapped.Disconnect = &Disconnect;
Overlapped.OutWindow = OutWindow;

if(ReadFileEx((HANDLE)Sock, Data, DATA_SIZE-1, &Overlapped,
(LPOVERLAPPED_COMPLETION_ROUTINE)&ReceiveCompletion) || GetLastError() == ERROR_IO_PENDING) {

SendData(Sock, "\x03\x04""Anonymous\r\n"); // Workaround for VC bug

while(!Disconnect) {
switch(MsgWaitForMultipleObjectsEx(0, 0, INFINITE, QS_ALLINPUT, MWMO_ALERTABLE)) {

case WAIT_OBJECT_0:
MSG msg;

while(PeekMessage(&msg, 0, 0, 0, PM_REMOVE)) {
UINT m = msg.message;
TranslateMessage(&msg);

if(msg.hwnd == InWindow && msg.message == WM_CHAR && msg.wParam == '\r') {
int Size = GetWindowTextLength(InWindow)+3;
char* Text = (char*)Alloc(Size);

if(!GetWindowText(InWindow, Text, Size-2))
Text[0] = '\0';

*(LPWORD)&Text[Size-3] = '\n\r';
Text[Size-1] = 0;

SendData(Sock, Text);
SetWindowText(InWindow, "");
} else
DispatchMessage(&msg);
}

if(!IsWindow(InWindow) || !IsWindow(OutWindow)) {
closesocket(Sock);
SleepEx(0, TRUE);
Disconnect = true;
}

break;

}
}
}
} else
closesocket(Sock);
}

void Main(void)
{
HINSTANCE RichEdit = LoadLibrary("RichEd20.dll");

if(!RichEdit) {
ExitProcess(ERROR_FILE_NOT_FOUND);
__assume(0); // Visual C++-specific
}

if(!InitWinsock()) {
HINSTANCE Mod = GetModuleHandle(0);

if(HWND OutWindow = CreateWindowEx(WS_EX_APPWINDOW | WS_EX_OVERLAPPEDWINDOW, "RICHEDIT20A",
"", WS_CAPTION | ES_AUTOVSCROLL | WS_MAXIMIZEBOX | WS_MINIMIZEBOX | WS_SIZEBOX
| WS_SYSMENU | ES_READONLY | ES_MULTILINE, CW_USEDEFAULT, CW_USEDEFAULT, 300, 300,
0, 0, Mod, 0)) {

if(HWND InWindow = CreateWindowEx(0, "EDIT", "MiniChat", WS_CAPTION | ES_AUTOHSCROLL
| WS_MAXIMIZEBOX | WS_MINIMIZEBOX | WS_SIZEBOX | WS_SYSMENU, 50, 50, 200, 45,
OutWindow, 0, Mod, 0)) {
RunMainLoop(OutWindow, InWindow);
DestroyWindow(InWindow);
}

DestroyWindow(OutWindow);
}

WSACleanup();
}

FreeLibrary(RichEdit);

ExitProcess(ERROR_SUCCESS);
}


i get all the time following errors:

Code Select Expand

--------------------Configuration: sky_Maincpp - Win32 Debug--------------------
Linking...
LIBCD.lib(crt0.obj) : error LNK2001: unresolved external symbol _main
Debug/sky_Maincpp.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

sky_Maincpp.exe - 2 error(s), 0 warning(s)

i think its got something to do how i create the project (win32 app/console app/mfc app and so forth)

help please

[Mephisto]

main() not Main().  And if it's a Win32 project it'll be WinMain().

[vonLandenhausen]

thx alot

[vonLandenhausen]

hmm, it eventually compiles but it is only a console. shouldnt it be a window?!

[Zakath]

Yes, it should be a window. What kind of project do you have this set up as?

[Spuck]

New -> Project -> Win32 Application
should i use a different kind of type?
i tried it with dev-c++ as well (without the pragma) and it creates a console app as well 
help please

[Mephisto]

Did you use main or WinMain?

[Skywing]

Just to clarify, this program was intended to be compiled with /ENTRY:Main (and without the CRT linked in).

Changing it to int main() should work, though.  If you don't want it to be linked as a console app, then change the subsystem setting to /subsystem:windows instead of /subsystem:console.
(This should be in your linker options.)

[vonLandenhausen]

thx mate. but tell me please where to learn such things? are so 133D only cauz of msdn.com?>.< i just admire your knowledge

[MyndFyre]

are so 133D only cauz of msdn.com?

Huh?

[Spuck]

133d = elite 

[vonLandenhausen]

Just to clarify, this program was intended to be compiled with /ENTRY:Main (and without the CRT linked in).

what is the CRT and how to link withou it? i already tried to find it out it with google...

[vonLandenhausen]

CRT = C Run-Time ??

[Zakath]

If this thread continues to go off-topic in such a flame-intensive way, it will be locked. This is your warning.