请教一个curl的问题

请教一个curl的问题

下面是线程函数体。
去掉了一些无关的东西，大体结构是这样的。trace文件里有curlErrFlag = 0， 但是没有resultCode = 的信息，说明是curl_easy_perform( )出的错。而且负责通信的另一端的人说，命令是传送过去并执行了的。
大牛们看看？
void slccorCurl_c::PerformCurl(const char* url,string userpwd, string xmlbuffer , string protocol )
{
try
{
CPFDEF::TraceBuffer_c trace;
trace.SetPacketLevel( 5 );

struct memoryStruct response;
response.memory=NULL;
response.size = 0;

curl_global_init(CURL_GLOBAL_ALL);
CURL *c = curl_easy_init();
if( ! c ) {

CPFDEF::Error_c err(SLCCOR_CURL_INIT_EXCEPTION,
"Error during curl initialisation");
err.SetLocation(__FILE__, __LINE__);

CPFCEC::ErrorLog_c::Send( err );

}

int curlErrFlag = 0;

if (( curl_easy_setopt(c, CURLOPT_URL, url)) != CURLE_OK ) curlErrFlag = 1;
//...a lot of curl_easy_setopt calling
if (( curl_easy_setopt(c, CURLOPT_SSL_VERIFYHOST, 0))!= CURLE_OK ) curlErrFlag = 1;

trace << " curlErrFlag = " << curlErrFlag << endl << flush ;

if ( curlErrFlag == 1 )
{
result = SLCCOR_CURL_ERROR;
}
else
{

CURLcode resultCode = curl_easy_perform( c );

trace << " resultCode = " << resultCode << endl << flush ;

if ( resultCode == CURLE_COULDNT_CONNECT || resultCode == CURLE_COULDNT_RESOLVE_HOST )
{
result = SLCCOR_NO_NE_CONNECT ;
}

if(response.memory)
{
xmlResponse = response.memory;
}

free (response.memory);

curl_easy_cleanup( c );
}
}
catch (...) {
//...
}

}

解决方法。 /tmp/cc1ounoj.o: in function `main': displayimage.cpp:(.text+0x6c): undefined reference to `cv::imread(std::basic_string, std::allocator > const&, int)' displayimage.cpp:(.text+0x10c): undefined reference to `cv::namedwindow(std::basic_string, std::allocator > const&, int)' displayimage.cpp:(.text+0x13a): undefined reference to `cv::_inputarray::_inputarray(cv::mat const&)' displayimage.cpp:(.text+0x16e): undefined reference to `cv::imshow(std::basic_string, std::allocator > const&, cv::_inputarray const&)' displayimage.cpp:(.text+0x190): undefined reference to `cv::waitkey(int)' /tmp/cc1ounoj.o: in function `cv::mat::~mat()': displayimage.cpp:(.text._zn2cv3matd2ev[_zn2cv3matd5ev]+0x39): undefined reference to `cv::fastfree(void*)' /tmp/cc1ounoj.o: in function `cv::mat::operator=(cv::mat const&)': displayimage.cpp:(.text._zn2cv3mataserks0_[cv::mat::operator=(cv::mat const&)]+0x