c - undefined reference 让我感到困惑

Question

我不知道为什么会出现引用错误，也不知道如何修复它们。我对此完全陌生，所以我们很乐意提供任何帮助。

据我所知，rpcdce.h 应该包含它引用的任何内容，确实如此，但就是行不通。我完全迷路了，我很抱歉提供了糟糕的信息。

// Added the pragma line below to work with Microsoft Visual Studio C++ 2005 Express edition
// Skype:TheUberOverLord
#pragma comment(lib, "Rpcrt4.lib")
// tab size: 2
// following special commands are recognized and handled by this client
//   #quit
//   #exit
//     terminate client
//   #dbgon
//     turn on debug printing of windows messages
//   #dbgoff
//     turn off debug printing of windows messages
//   #connect
//     discover skype api
//   #disconnect
//     terminate connection to skype api
// all other commands are sent "as is" directly to Skype
// (no UTF-8 translation is done at present)

#include <conio.h>
#include <stdio.h>
#include <string.h>
#include <process.h>

#include <windows.h>
#include <rpcdce.h>

HWND hInit_MainWindowHandle;
HINSTANCE hInit_ProcessHandle;
char acInit_WindowClassName[128];
HANDLE hGlobal_ThreadShutdownEvent;
bool volatile fGlobal_ThreadRunning=true;
UINT uiGlobal_MsgID_SkypeControlAPIAttach;
UINT uiGlobal_MsgID_SkypeControlAPIDiscover;
HWND hGlobal_SkypeAPIWindowHandle=NULL;
#if defined(_DEBUG)
    bool volatile fGlobal_DumpWindowsMessages=true;
#else
    bool volatile fGlobal_DumpWindowsMessages=false;
#endif
DWORD ulGlobal_PromptConsoleMode=0;
HANDLE volatile hGlobal_PromptConsoleHandle=NULL;

enum {
    SKYPECONTROLAPI_ATTACH_SUCCESS=0,                               // Client is successfully attached and API window handle can be found in wParam parameter
    SKYPECONTROLAPI_ATTACH_PENDING_AUTHORIZATION=1, // Skype has acknowledged connection request and is waiting for confirmation from the user.
                                                                                                    // The client is not yet attached and should wait for SKYPECONTROLAPI_ATTACH_SUCCESS message
    SKYPECONTROLAPI_ATTACH_REFUSED=2,                               // User has explicitly denied access to client
    SKYPECONTROLAPI_ATTACH_NOT_AVAILABLE=3,                 // API is not available at the moment. For example, this happens when no user is currently logged in.
                                                                                                    // Client should wait for SKYPECONTROLAPI_ATTACH_API_AVAILABLE broadcast before making any further
                                                                                                    // connection attempts.
    SKYPECONTROLAPI_ATTACH_API_AVAILABLE=0x8001
};

bool Global_Console_ReadRow( char *pacPromptBuffer, unsigned int uiMaxLength)
    {
    HANDLE hConsoleHandle, hDuplicatedConsoleHandle;
    DWORD ulCharactersRead, ulConsoleMode;
    unsigned int uiNewLength;
    BOOL fReadConsoleResult;
    bool fReturnStatus;
    char cCharacter;

    fReturnStatus=false;
    while((hConsoleHandle=GetStdHandle(STD_INPUT_HANDLE))!=INVALID_HANDLE_VALUE)
        {
        if( DuplicateHandle( GetCurrentProcess(), hConsoleHandle,
                GetCurrentProcess(), &hDuplicatedConsoleHandle, 0, FALSE,
                DUPLICATE_SAME_ACCESS)==FALSE )
            break;
        GetConsoleMode( hDuplicatedConsoleHandle, &ulConsoleMode);
        SetConsoleMode( hDuplicatedConsoleHandle, ENABLE_LINE_INPUT|ENABLE_PROCESSED_INPUT|ENABLE_ECHO_INPUT);
        hGlobal_PromptConsoleHandle=hDuplicatedConsoleHandle;
        ulGlobal_PromptConsoleMode=ulConsoleMode;
        fReadConsoleResult=ReadConsole( hGlobal_PromptConsoleHandle,
            (LPVOID)pacPromptBuffer, uiMaxLength, &ulCharactersRead, NULL);
        if( hGlobal_PromptConsoleHandle==(HANDLE)0 )
            break;
        hGlobal_PromptConsoleHandle=(HANDLE)0;
        SetConsoleMode( hDuplicatedConsoleHandle, ulConsoleMode);
        CloseHandle(hDuplicatedConsoleHandle);
        if( fReadConsoleResult==FALSE || ulCharactersRead>uiMaxLength )
            break;
        pacPromptBuffer[ulCharactersRead]=0;
        uiNewLength=ulCharactersRead;
        while(uiNewLength!=0)
            {
            cCharacter=pacPromptBuffer[uiNewLength-1];
            if( cCharacter!='\r' && cCharacter!='\n' )
                break;
            uiNewLength--;
            }
        pacPromptBuffer[uiNewLength]=0;
        fReturnStatus=true;
        break;
        }
    if( fReturnStatus==false )
        pacPromptBuffer[0]=0;
    return(fReturnStatus);
    }

void Global_Console_CancelReadRow(void)
    {
    if( hGlobal_PromptConsoleHandle!=(HANDLE)0 )
        {
        SetConsoleMode( hGlobal_PromptConsoleHandle, ulGlobal_PromptConsoleMode);
        CloseHandle(hGlobal_PromptConsoleHandle);
        hGlobal_PromptConsoleHandle=(HANDLE)0;
        }
    }

static LRESULT APIENTRY SkypeAPITest_Windows_WindowProc(
    HWND hWindow, UINT uiMessage, WPARAM uiParam, LPARAM ulParam)
    {
    LRESULT lReturnCode;
    bool fIssueDefProc;

    lReturnCode=0;
    fIssueDefProc=false;
    switch(uiMessage)
        {
        case WM_DESTROY:
            hInit_MainWindowHandle=NULL;
            PostQuitMessage(0);
            break;
        case WM_COPYDATA:
            if( hGlobal_SkypeAPIWindowHandle==(HWND)uiParam )
                {
                PCOPYDATASTRUCT poCopyData=(PCOPYDATASTRUCT)ulParam;
                printf( "Message from Skype(%u): %.*s\n", poCopyData->dwData, poCopyData->cbData, poCopyData->lpData);
                lReturnCode=1;
                }
            break;
        default:
            if( uiMessage==uiGlobal_MsgID_SkypeControlAPIAttach )
                {
                switch(ulParam)
                    {
                    case SKYPECONTROLAPI_ATTACH_SUCCESS:
                        printf("!!! Connected; to terminate issue #disconnect\n");
                        hGlobal_SkypeAPIWindowHandle=(HWND)uiParam;
                        break;
                    case SKYPECONTROLAPI_ATTACH_PENDING_AUTHORIZATION:
                        printf("!!! Pending authorization\n");
                        break;
                    case SKYPECONTROLAPI_ATTACH_REFUSED:
                        printf("!!! Connection refused\n");
                        break;
                    case SKYPECONTROLAPI_ATTACH_NOT_AVAILABLE:
                        printf("!!! Skype API not available\n");
                        break;
                    case SKYPECONTROLAPI_ATTACH_API_AVAILABLE:
                        printf("!!! Try connect now (API available); issue #connect\n");
                        break;
                    }
                lReturnCode=1;
                break;
                }
            fIssueDefProc=true;
            break;
        }
    if( fIssueDefProc )
        lReturnCode=DefWindowProc( hWindow, uiMessage, uiParam, ulParam);
    if( fGlobal_DumpWindowsMessages )
        {
        printf( "WindowProc: hWindow=0x%08X, MainWindow=0x%08X, Message=%5u, WParam=0x%08X, LParam=0x%08X; Return=%ld%s\n",
            hWindow, hInit_MainWindowHandle, uiMessage, uiParam, ulParam, lReturnCode, fIssueDefProc? " (default)":"");
        }
    return(lReturnCode);
    }

bool Initialize_CreateWindowClass(void)
    {
    unsigned char *paucUUIDString;
    RPC_STATUS lUUIDResult;
    bool fReturnStatus;
    UUID oUUID;

    fReturnStatus=false;
    lUUIDResult=UuidCreate(&oUUID);
    hInit_ProcessHandle=(HINSTANCE)OpenProcess( PROCESS_DUP_HANDLE, FALSE, GetCurrentProcessId());
    if( hInit_ProcessHandle!=NULL && (lUUIDResult==RPC_S_OK || lUUIDResult==RPC_S_UUID_LOCAL_ONLY) )
        {
        if( UuidToString( &oUUID, &paucUUIDString)==RPC_S_OK )
            {
            WNDCLASS oWindowClass;

            strcpy( acInit_WindowClassName, "Skype-API-Test-");
            strcat( acInit_WindowClassName, (char *)paucUUIDString);

            oWindowClass.style=CS_HREDRAW|CS_VREDRAW|CS_DBLCLKS;
            oWindowClass.lpfnWndProc=(WNDPROC)&SkypeAPITest_Windows_WindowProc;
            oWindowClass.cbClsExtra=0;
            oWindowClass.cbWndExtra=0;
            oWindowClass.hInstance=hInit_ProcessHandle;
            oWindowClass.hIcon=NULL;
            oWindowClass.hCursor=NULL;
            oWindowClass.hbrBackground=NULL;
            oWindowClass.lpszMenuName=NULL;
            oWindowClass.lpszClassName=acInit_WindowClassName;

            if( RegisterClass(&oWindowClass)!=0 )
                fReturnStatus=true;

            RpcStringFree(&paucUUIDString);
            }
        }
    if( fReturnStatus==false )
        CloseHandle(hInit_ProcessHandle),hInit_ProcessHandle=NULL;
    return(fReturnStatus);
    }

void DeInitialize_DestroyWindowClass(void)
    {
    UnregisterClass( acInit_WindowClassName, hInit_ProcessHandle);
    CloseHandle(hInit_ProcessHandle),hInit_ProcessHandle=NULL;
    }

bool Initialize_CreateMainWindow(void)
    {
    hInit_MainWindowHandle=CreateWindowEx(WS_EX_APPWINDOW|WS_EX_WINDOWEDGE,
        acInit_WindowClassName, "", WS_BORDER|WS_SYSMENU|WS_MINIMIZEBOX,
        CW_USEDEFAULT, CW_USEDEFAULT, 128, 128, NULL, 0, hInit_ProcessHandle, 0);

    return(hInit_MainWindowHandle!=NULL? true:false);
    }

void DeInitialize_DestroyMainWindow(void)
    {
    if( hInit_MainWindowHandle!=NULL )
        DestroyWindow(hInit_MainWindowHandle),hInit_MainWindowHandle=NULL;
    }

void Global_MessageLoop(void)
    {
    MSG oMessage;

    while(GetMessage( &oMessage, 0, 0, 0)!=FALSE)
        {
        TranslateMessage(&oMessage);
        DispatchMessage(&oMessage);
        }
    }

void __cdecl Global_InputProcessingThread(void *)
    {
    static char acInputRow[1024];
    bool fProcessed;

    if( SendMessageTimeout( HWND_BROADCAST, uiGlobal_MsgID_SkypeControlAPIDiscover, (WPARAM)hInit_MainWindowHandle, 0, SMTO_ABORTIFHUNG, 1000, NULL)!=0 )
        {
        while(Global_Console_ReadRow( acInputRow, sizeof(acInputRow)-1))
            {
            if( _stricmp( acInputRow, "#quit")==0 ||
                    _stricmp( acInputRow, "#exit")==0 )
                break;
            fProcessed=false;
            if( _stricmp( acInputRow, "#dbgon")==0 )
                {
                printf( "SkypeControlAPIAttach=%u, SkypeControlAPIDiscover=%u, hInit_MainWindowHandle=0x%08lX\n",
                    uiGlobal_MsgID_SkypeControlAPIAttach, uiGlobal_MsgID_SkypeControlAPIDiscover, hInit_MainWindowHandle);
                fGlobal_DumpWindowsMessages=true,fProcessed=true;
                }
            if( _stricmp( acInputRow, "#dbgoff")==0 )
                fGlobal_DumpWindowsMessages=false,fProcessed=true;
            if( _stricmp( acInputRow, "#connect")==0 )
                {
                SendMessageTimeout( HWND_BROADCAST, uiGlobal_MsgID_SkypeControlAPIDiscover, (WPARAM)hInit_MainWindowHandle, 0, SMTO_ABORTIFHUNG, 1000, NULL);
                fProcessed=true;
                }
            if( _stricmp( acInputRow, "#disconnect")==0 )
                {
                hGlobal_SkypeAPIWindowHandle=NULL;
                printf("!!! Disconnected\n");
                fProcessed=true;
                }
            if( fProcessed==false && hGlobal_SkypeAPIWindowHandle!=NULL )
                {
                COPYDATASTRUCT oCopyData;

                // send command to skype
                oCopyData.dwData=0;
                oCopyData.lpData=acInputRow;
                oCopyData.cbData=strlen(acInputRow)+1;
                if( oCopyData.cbData!=1 )
                    {
                    if( SendMessage( hGlobal_SkypeAPIWindowHandle, WM_COPYDATA, (WPARAM)hInit_MainWindowHandle, (LPARAM)&oCopyData)==FALSE )
                        {
                        hGlobal_SkypeAPIWindowHandle=NULL;
                        printf("!!! Disconnected\n");
                        }
                    }
                }
            }
        }
    SendMessage( hInit_MainWindowHandle, WM_CLOSE, 0, 0);
    SetEvent(hGlobal_ThreadShutdownEvent);
    fGlobal_ThreadRunning=false;
    }

int main(void)
    {
    // create window class
    //   create dummy/hidden window for processing messages
    //     run message loop thread
    //       do application control until exit
    //       exit: send QUIT message to our own window
    //             wait until thred terminates
    //   destroy main window
    // destroy window class
    uiGlobal_MsgID_SkypeControlAPIAttach=RegisterWindowMessage("SkypeControlAPIAttach");
    uiGlobal_MsgID_SkypeControlAPIDiscover=RegisterWindowMessage("SkypeControlAPIDiscover");
    if( uiGlobal_MsgID_SkypeControlAPIAttach!=0 && uiGlobal_MsgID_SkypeControlAPIDiscover!=0 )
        {
        if( Initialize_CreateWindowClass() )
            {
            if( Initialize_CreateMainWindow() )
                {
                hGlobal_ThreadShutdownEvent=CreateEvent( NULL, TRUE, FALSE, NULL);
                if( hGlobal_ThreadShutdownEvent!=NULL )
                    {
                    if( _beginthread( &Global_InputProcessingThread, 64*1024, NULL)!=(unsigned long)-1 )
                        {
                        Global_MessageLoop();
                        Global_Console_CancelReadRow();
                        WaitForSingleObject( hGlobal_ThreadShutdownEvent, INFINITE);
                        }
                    CloseHandle(hGlobal_ThreadShutdownEvent);
                    }
                DeInitialize_DestroyMainWindow();
                }
            DeInitialize_DestroyWindowClass();
            }
        }
    }

错误信息:

Debug\msgapitest.o||In function `Z28Initialize_CreateWindowClassv':|
C:\Users\Morten\Desktop\msgapitest\msgapitest.cpp|180|undefined reference to `UuidCreate@4'|
C:\Users\Morten\Desktop\msgapitest\msgapitest.cpp|184|undefined reference to `UuidToStringA@8'|
C:\Users\Morten\Desktop\msgapitest\msgapitest.cpp|205|undefined reference to `RpcStringFreeA@4'|
||=== Build finished: 3 errors, 0 warnings (0 minutes, 0 seconds) ===|

Answer 1

我刚刚在 Visual Studio 2010 Pro 中创建了一个新的 Win32 控制台应用程序项目，添加了一个 main.c，将您的代码复制进去，它可以正常编译和链接。

我有 RpcRT4.lib:

c:\Program Files\Microsoft SDKs\Windows\v7.1\Lib\
c:\Program Files\Microsoft SDKs\Windows\v7.1\Lib\x64\
c:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Lib\x64\
c:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Lib\IA64\
c:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Lib\

连同其他评论，我假设您的链接器不知道在哪里可以找到该库。你知道它在你系统上的什么位置吗？您可以将它的路径添加到 Visual Studio 项目属性中包含的库目录中。