ACE应用程序链接错误 error LNK2019 的解决办法
读者水平:初级
摘要：文本简要指出如何正确编译和链接ACE应用程序。
对于新手来说，ACE开发环境，会是一团谜团，如何正确配置开发者机器，快速体验ACE，
就是本系列文章的目的。本文仅解决如何解决LNK2019错误
环境：
ACE版本 5.5.1
操作系统 Windows xp professional sp2
开发环境 Microsoft Visual C++ 2005 77626-009-0000007-41235
下面的代码是服务的主程序
//
@file: RegisterServer.cpp :
//
@description: Defines the entry point for the GameService Daemon application.
//
@date: 2006-07-06
//
@author: Jiangtao<2005119@gmail.com>
#ifdef _DEBUG
#define
ACE_NDEBUG 0
#define
ACE_NTRACE 0
#endif
#include
"
stdafx.h
"
#include
"
ACE/Filecache.h
"
#include
"
ACE/Log_Msg.h
"
#include
"
ACE/OS_NS_signal.h
"
#include
"
ACE/Service_Config.h
"
#ifdef ACE_HAS_SIG_C_FUNC
#pragma message (
"
ACE_HAS_SIG_C_FUNC
"
)
extern
"
C
"
{
#endif
/* ACE_HAS_SIG_C_FUNC */
//
call exit() so that static destructors get called
static
void
handler (
int
)
{
delete (ACE_Filecache
*
) ACE_Filecache::instance ();
ACE_OS::exit (
0
);
}
#ifdef ACE_HAS_SIG_C_FUNC
}
#endif
/* ACE_HAS_SIG_C_FUNC */
int
ACE_TMAIN(
int
argc, ACE_TCHAR
*
argv[])
{
ACE_DEBUG((LM_INFO,ACE_TEXT(
"
启动服务\n
"
)));
ACE_Service_Config daemon;
ACE_OS::signal (SIGCHLD, SIG_IGN);
//
SigAction not needed since the handler will shutdown the server.
ACE_OS::signal (SIGINT, (ACE_SignalHandler) handler);
ACE_OS::signal (SIGUSR2, (ACE_SignalHandler) handler);
if
(daemon.open (argc, argv, ACE_DEFAULT_LOGGER_KEY,
0
)
!=
0
)
ACE_ERROR_RETURN ((LM_ERROR,
"
%p\n
"
,
"
open
"
),
1
);
//
The configured service creates threads, and the
//
server won't exit until the threads die.
//
Run forever, performing the configured services until we receive
//
a SIGINT.
return
0
;
}
服务加载的配置文件
###############################################################################
# file svc.conf
###############################################################################
dynamic GameService Service_Object
*
GameService: _make_GameServer_T() active
出错提示:
----- Build started: Project: RegisterServer, Configuration: Debug Win32 ------
Compiling
RegisterServer.cpp
Linking
RegisterServer.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) int __cdecl ace_os_wmain_i(class ACE_Main_Base &,int,wchar_t * * const)" (__imp_?ace_os_wmain_i@@YAHAAVACE_Main_Base@@HQAPA_W@Z) referenced in function _wmain
RegisterServer.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static int __cdecl ACE_Service_Config::open(int,wchar_t * * const,wchar_t const *,int,int,int)" (__imp_?open@ACE_Service_Config@@SAHHQAPA_WPB_WHHH@Z) referenced in function "int __cdecl ace_wmain_i(int,wchar_t * * const)" (?ace_wmain_i@@YAHHQAPA_W@Z)
D:\ACE_OUTPUT\Game\\RegisterServerd.exe : fatal error LNK1120: 2 unresolved externals
Build log was saved at "file://d:\My Sources\RegisterService\RegisterServer\Debug\BuildLog.htm"
RegisterServer - 3 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 1 up-to-date, 0 skipped ==========
问题分析
出错信息显示，不能解析函数ace_os_wmain_i()以及 ACE_Service_Config::open()。
从这里可以看出，链接器需要UNICODE版本的ace库，而我们在生成ACE的时候，并没有生成宽字符
的UNICODE版本。
解决办法：
打开项目的属性页，找到配置属性，在字符集中，选择多字节字符集。再重新编译，问题解决。