在库链接期间未找到引用 我在C++中创建了一个名为LIbPARSE的库，该代码被另一个名为LIPBITMPMSG的库使用。

我一直试图在test.cpp中测试libitcmpmsg，但是当我尝试构建它时，编译器返回以下消息：

$libpath/libitcmpmsg.so: reference not found to "void MSG_PARSER::WriteBigEndian<unsigned char>(std::vector<unsigned char, std::allocator<unsigned char> &, unsingned char)"
$libpath/libitcmpmsg.so: reference not found to "unsigned char* MSG_PARSER::ReadBigEndian<unsigned char>(unsigned char&, unsigned char*, unsigned int&)"
$libpath/libitcmpmsg.so: reference not found to "MSG_PARSER::ReadFixedLengthString(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, unsigned char*, int, unsigned int&)"
$libpath/libitcmpmsg.so: reference not found to "MSG_PARSER::WriteFixedLengthString(std::vector<unsigned char, std::allocator<unsigned char> >&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned int)"

---

$libpath/libitcmpmsg.so:reference not found to“void MSG_PARSER:：WriteBigEndian（std:：vector您必须在cpp中实例化专门的模板类，或者将模板类体放在标题中：
您的模板函数（函数体）是在标题（h）还是正文（cpp）中定义的文件？它们在cpp文件中定义。有关模板函数，请参阅。其中定义了
ReadFixedLengthString
和
WriteFixedLengthString
可能会有所帮助。ReadFixedLengthString和WriteFixedLengthString是在msg_parser.cpp中定义的。我已将模板函数的位置重新定位到头文件，并且错误与它们已经消失了。不使用模板的函数我也会将它们移动到标题和编译的代码中。为什么我也必须移动非模板函数？“为什么我也必须移动非模板函数？”？“-您不必在头文件中定义非模板函数。您对函数的定义
ReadFixedLengthString
和
WriteFixedLengthString
可能有其他错误。但由于您没有显示此定义（不是声明），我们只能猜测其推理。我将模板函数体更改为标题，但它不起作用。然而，作为一种尝试，我也尝试将普通函数更改为标题，它起了作用。为什么我还必须将普通函数替换为标题？@AndréMachoski，除了一些小错误之外（忘记保存文件等），我建议您没有使用正确的命令进行链接（可能缺少指定所需所有文件的参数），因此将它们添加到标题中就不需要链接了。
    template <class T>
    void WriteBigEndian(std::vector<uint8_t>& target, T source);

    template <class T>
    uint8_t* ReadBigEndian(T &target, uint8_t* source, uint32_t &available);

    uint8_t* ReadFixedLengthString(string& target, uint8_t *source, int size, uint32_t &available);

    void WriteFixedLengthString(std::vector<uint8_t> &target, const string& source, uint32_t size);

#include "ptcinteraction.h"
#include "msg_parser.h"
#include <stdint.h>

using namespace PTC_INTERACTION;
using namespace MSG_PARSER;


PtcInteraction::PtcInteraction( std::vector<uint8_t> &data )
{
    m_msgBuffer.clear();
    uint32_t tavailable = static_cast<uint32_t>(data.size());
    uint8_t *tsource = &data[0];
    uint8_t value = 0;

    tsource = ReadFixedLengthString(m_message.railScac, tsource,  SCAC_SIZE, tavailable);
    tsource = ReadBigEndian<uint8_t>(m_message.sizeOfPromptTxt, tsource, tavailable );
    tsource = ReadFixedLengthString(m_message.promptTxt, tsource,  m_message.sizeOfPromptTxt, tavailable);
    tsource = ReadBigEndian<uint8_t>(m_message.sizeOfKeyPressedTxt, tsource, tavailable );
    tsource = ReadFixedLengthString(m_message.keyPressedTxt, tsource,  m_message.sizeOfKeyPressedTxt, tavailable);

    if((&data[0] + data.size()) == tsource)
    {
        m_msgBuffer = data;
    }
    else
    {
        m_msgBuffer = {};
    }
}

PtcInteraction::PtcInteraction( OCCPTCMSG::PtcInteractionT &ptcInteraction)
{
    m_msgBuffer.clear();
    m_message = ptcInteraction;

    WriteFixedLengthString(m_msgBuffer, ptcInteraction.railScac, SCAC_SIZE);
    WriteBigEndian<uint8_t>(m_msgBuffer, ptcInteraction.sizeOfPromptTxt );
    .
    .
    .

#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include "ptcinteraction.h"
#include "occptcmessages_generated.h"
#include "msg_parser.h"
#include <cstdio>

using namespace PTC_INTERACTION;

int main(void)
{
    OCCPTCMSG::PtcInteractionT teste;


    teste.railScac = "abcd";
    teste.promptTxt = "message test";
    teste.sizeOfPromptTxt = teste.promptTxt.size();
    teste.keyPressedTxt = "test";
    teste.sizeOfKeyPressedTxt = teste.keyPressedTxt.size();

    PTC_INTERACTION::PtcInteraction ptcInter(teste);

    PTC_INTERACTION::PtcInteraction ptcInter2(ptcInter.m_msgBuffer);

    if ( (ptcInter.m_message.railScac == ptcInter2.m_message.railScac) &&
       (ptcInter.m_message.promptTxt == ptcInter2.m_message.promptTxt) &&
       (ptcInter.m_message.sizeOfPromptTxt == ptcInter2.m_message.sizeOfPromptTxt) &&
       (ptcInter.m_message.keyPressedTxt == ptcInter2.m_message.keyPressedTxt) &&
       (ptcInter.m_message.sizeOfKeyPressedTxt == ptcInter2.m_message.sizeOfKeyPressedTxt) )
    {
        std::cout << "Serialization and deserialization succeeded" << std::endl;
    }

}