版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/yang332233/article/details/83657735
我电脑ubuntu16.04，我们工程里面用的protobuf-3.1.0版本的，是指定目录安装的，我打开其安装目录，
所以不管是这个，其他的比如opencv也是这样子的，编译生成这三种
在QT工程里面的pro这么写的：
OPENCV_ROOT_PATH = /home/software
CAFFE_ROOT_PATH = /media/d/caffe_root
PROTOBUF_ROOT_PATH = /home/software/protobuf-3.1.0
INCLUDEPATH += $${OPENCV_ROOT_PATH}/include \
$${OPENCV_ROOT_PATH}/include/opencv \
$${OPENCV_ROOT_PATH}/include/opencv2 \
$${CAFFE_ROOT_PATH}/include \
$${CAFFE_ROOT_PATH}/build/include \
$${PROTOBUF_ROOT_PATH}/include \
/usr/local/cuda-8.0/include
LIBS += -L$${OPENCV_ROOT_PATH}/lib \
-L$${CAFFE_ROOT_PATH}/build/lib \
-L$${PROTOBUF_ROOT_PATH}/lib \
-L/usr/local/cuda-8.0/lib64
LIBS += -lopencv_core \
-lopencv_highgui \
-lopencv_imgproc \
-lopencv_imgcodecs \
-lopencv_videoio \
-lcaffe我不知道这里为什么没有加LIBS += -lprotobuf的
然后我按照这个博客测试protobuf的用法https://blog.csdn.net/u014538198/article/details/72674742
需要用系统自带的proto，我搜索我电脑proto放在哪里，/usr/bin/protoc 是在这里，然后敲命令：
/usr/bin$ ./protoc -I=/media/d_2/everyday/1102/proto_test/src --cpp_out=/media/d_2/everyday/1102/proto_test/out /media/d_2/everyday/1102/proto_test/src/person.proto 果真生成了两个文件
/media/d_2/everyday/1102/proto_test/out/person.pb.cc
/media/d_2/everyday/1102/proto_test/out/person.pb.h
然后我各种locate 查找库文件和头文件在哪里，库文件在/usr/lib/x86_64-linux-gnu,头文件不太好找，locate google才翻到的，经过对比比较测试，pro这么写才正确：
QT += core
QT -= gui
CONFIG += c++11
TARGET = 1102test_proto
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
INCLUDEPATH += /usr/include
LIBS += -L/usr/lib/x86_64-linux-gnu
LIBS += -lprotobuf
SOURCES += main.cpp \
person.pb.cc
DEFINES += QT_DEPRECATED_WARNINGS
HEADERS += \
person.pb.h
#include "person.pb.h"
#include<iostream>
#include<fstream>
int main(int argc, char *argv[])
{
GOOGLE_PROTOBUF_VERIFY_VERSION;
Test::Person person;
person.set_id( 123 );
person.set_name( "abc" );
person.set_email( "[email protected]" );
std::fstream out( "/media/d_2/everyday/1102/person.proto", std::ios::out | std::ios::binary | std::ios::trunc );
person.SerializeToOstream( &out );
out.close();
// 从文件中读取数据， 并且反序列化
Test::Person person1;
std::fstream in( "/media/d_2/everyday/1102/person.proto", std::ios::in | std::ios::binary );
if ( !person1.ParseFromIstream( &in ) ) {
std::cerr << "Failed to parse person.pb." << std::endl;
exit(1);
}
std::cout << "ID: " << person1.id() << std::endl;
std::cout << "name: " << person1.name() << std::endl;
if ( person1.has_email() ) {
std::cout << "e-mail: " << person1.email() << std::endl;
}
// Optional: Delete all global objects allocated by libprotobuf.
google::protobuf::ShutdownProtobufLibrary();
getchar();
return 0;
return 1;
}
一开始LIBS += -lprotobuf这个没有写，编译可以通过，但是运行各种报错，什么未定义的引用，如下，所以以后出现什么未定义的引用，就是库的原因，有一个问题是工程里面没有加LIBS += -lprotobuf可以没问题，不知道原因．．．
17:01:43: 为项目1102test_proto执行步骤 ...
17:01:43: 配置没有改变, 跳过 qmake 步骤。
17:01:43: 正在启动 "/usr/bin/make"
g++ -Wl,-rpath,/home/yhl/Qt/5.9.1/gcc_64/lib -o 1102test_proto main.o person.pb.o -L/usr/lib/x86_64-linux-gnu -L/home/yhl/Qt/5.9.1/gcc_64/lib -lQt5Core -lpthread
main.o：在函数‘main’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/main.cpp:7：对‘google::protobuf::internal::VerifyVersion(int, int, char const*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/main.cpp:14：对‘google::protobuf::Message::SerializeToOstream(std::ostream*) const’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/main.cpp:20：对‘google::protobuf::Message::ParseFromIstream(std::istream*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/main.cpp:32：对‘google::protobuf::ShutdownProtobufLibrary()’未定义的引用
main.o：在函数‘google::protobuf::internal::GetEmptyStringAlreadyInited[abi:cxx11]()’中：
/usr/include/google/protobuf/generated_message_util.h:80：对‘google::protobuf::internal::empty_string_[abi:cxx11]’未定义的引用
/usr/include/google/protobuf/generated_message_util.h:81：对‘google::protobuf::internal::empty_string_[abi:cxx11]’未定义的引用
person.pb.o：在函数‘Test::protobuf_AssignDesc_person_2eproto()’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:33：对‘google::protobuf::DescriptorPool::generated_pool()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:34：对‘google::protobuf::DescriptorPool::FindFileByName(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) const’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:35：对‘google::protobuf::internal::LogMessage::LogMessage(google::protobuf::LogLevel, char const*, int)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:35：对‘google::protobuf::internal::LogMessage::operator<<(char const*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:35：对‘google::protobuf::internal::LogFinisher::operator=(google::protobuf::internal::LogMessage&)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:35：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:52：对‘google::protobuf::DescriptorPool::generated_pool()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:52：对‘google::protobuf::MessageFactory::generated_factory()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:52：对‘google::protobuf::internal::GeneratedMessageReflection::GeneratedMessageReflection(google::protobuf::Descriptor const*, google::protobuf::Message const*, int const*, int, int, int, google::protobuf::DescriptorPool const*, google::protobuf::MessageFactory*, int)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:35：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
person.pb.o：在函数‘Test::(anonymous namespace)::protobuf_RegisterTypes(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:66：对‘google::protobuf::MessageFactory::InternalRegisterGeneratedMessage(google::protobuf::Descriptor const*, google::protobuf::Message const*)’未定义的引用
person.pb.o：在函数‘Test::protobuf_AddDesc_person_2eproto()’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:80：对‘google::protobuf::internal::VerifyVersion(int, int, char const*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:84：对‘google::protobuf::DescriptorPool::InternalAddGeneratedFile(void const*, int)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:86：对‘google::protobuf::MessageFactory::InternalRegisterGeneratedFile(char const*, void (*)(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&))’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:89：对‘google::protobuf::internal::OnShutdown(void (*)())’未定义的引用
person.pb.o：在函数‘Test::Person::Person()’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:108：对‘google::protobuf::UnknownFieldSet::UnknownFieldSet()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:108：对‘google::protobuf::UnknownFieldSet::~UnknownFieldSet()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:108：对‘google::protobuf::Message::~Message()’未定义的引用
person.pb.o：在函数‘Test::Person::Person(Test::Person const&)’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:117：对‘google::protobuf::UnknownFieldSet::UnknownFieldSet()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:117：对‘google::protobuf::UnknownFieldSet::~UnknownFieldSet()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:117：对‘google::protobuf::Message::~Message()’未定义的引用
person.pb.o：在函数‘Test::Person::~Person()’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:132：对‘google::protobuf::UnknownFieldSet::~UnknownFieldSet()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:132：对‘google::protobuf::Message::~Message()’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedInputStream::ReadTagWithCutoff(unsigned int)’中：
/usr/include/google/protobuf/io/coded_stream.h:924：对‘google::protobuf::io::CodedInputStream::ReadTagFallback()’未定义的引用
person.pb.o：在函数‘Test::Person::MergePartialFromCodedStream(google::protobuf::io::CodedInputStream*)’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:200：对‘google::protobuf::internal::WireFormatLite::ReadString(google::protobuf::io::CodedInputStream*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:232：对‘google::protobuf::internal::WireFormatLite::ReadString(google::protobuf::io::CodedInputStream*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:252：对‘google::protobuf::internal::WireFormat::SkipField(google::protobuf::io::CodedInputStream*, unsigned int, google::protobuf::UnknownFieldSet*)’未定义的引用
person.pb.o：在函数‘Test::Person::SerializeWithCachedSizes(google::protobuf::io::CodedOutputStream*) const’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:277：对‘google::protobuf::internal::WireFormatLite::WriteStringMaybeAliased(int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, google::protobuf::io::CodedOutputStream*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:282：对‘google::protobuf::internal::WireFormatLite::WriteInt32(int, int, google::protobuf::io::CodedOutputStream*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:292：对‘google::protobuf::internal::WireFormatLite::WriteStringMaybeAliased(int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, google::protobuf::io::CodedOutputStream*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:297：对‘google::protobuf::internal::WireFormat::SerializeUnknownFields(google::protobuf::UnknownFieldSet const&, google::protobuf::io::CodedOutputStream*)’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedOutputStream::WriteTagToArray(unsigned int, unsigned char*)’中：
/usr/include/google/protobuf/io/coded_stream.h:1083：对‘google::protobuf::io::CodedOutputStream::WriteVarint32FallbackToArray(unsigned int, unsigned char*)’未定义的引用
person.pb.o：在函数‘google::protobuf::internal::WireFormatLite::WriteStringToArray(int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned char*)’中：
/usr/include/google/protobuf/wire_format_lite_inl.h:749：对‘google::protobuf::io::CodedOutputStream::WriteStringWithSizeToArray(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned char*)’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedOutputStream::WriteTagToArray(unsigned int, unsigned char*)’中：
/usr/include/google/protobuf/io/coded_stream.h:1083：对‘google::protobuf::io::CodedOutputStream::WriteVarint32FallbackToArray(unsigned int, unsigned char*)’未定义的引用
/usr/include/google/protobuf/io/coded_stream.h:1083：对‘google::protobuf::io::CodedOutputStream::WriteVarint32FallbackToArray(unsigned int, unsigned char*)’未定义的引用
person.pb.o：在函数‘google::protobuf::internal::WireFormatLite::WriteStringToArray(int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned char*)’中：
/usr/include/google/protobuf/wire_format_lite_inl.h:749：对‘google::protobuf::io::CodedOutputStream::WriteStringWithSizeToArray(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned char*)’未定义的引用
person.pb.o：在函数‘Test::Person::SerializeWithCachedSizesToArray(unsigned char*) const’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:334：对‘google::protobuf::internal::WireFormat::SerializeUnknownFieldsToArray(google::protobuf::UnknownFieldSet const&, unsigned char*)’未定义的引用
person.pb.o：在函数‘Test::Person::ByteSize() const’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:369：对‘google::protobuf::internal::WireFormat::ComputeUnknownFieldsSize(google::protobuf::UnknownFieldSet const&)’未定义的引用
person.pb.o：在函数‘Test::Person::MergeFrom(google::protobuf::Message const&)’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:378：对‘google::protobuf::internal::LogMessage::LogMessage(google::protobuf::LogLevel, char const*, int)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:378：对‘google::protobuf::internal::LogMessage::operator<<(char const*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:378：对‘google::protobuf::internal::LogFinisher::operator=(google::protobuf::internal::LogMessage&)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:378：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:383：对‘google::protobuf::internal::ReflectionOps::Merge(google::protobuf::Message const&, google::protobuf::Message*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:378：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
person.pb.o：在函数‘Test::Person::MergeFrom(Test::Person const&)’中：
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:390：对‘google::protobuf::internal::LogMessage::LogMessage(google::protobuf::LogLevel, char const*, int)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:390：对‘google::protobuf::internal::LogMessage::operator<<(char const*)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:390：对‘google::protobuf::internal::LogFinisher::operator=(google::protobuf::internal::LogMessage&)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:390：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:402：对‘google::protobuf::UnknownFieldSet::MergeFrom(google::protobuf::UnknownFieldSet const&)’未定义的引用
/media/d/Yang/Myproject/build-1102test_proto-Desktop_Qt_5_9_1_GCC_64bit-Debug/../1102test_proto/person.pb.cc:390：对‘google::protobuf::internal::LogMessage::~LogMessage()’未定义的引用
person.pb.o：在函数‘google::protobuf::Closure::Closure()’中：
/usr/include/google/protobuf/stubs/common.h:855：对‘vtable for google::protobuf::Closure’未定义的引用
person.pb.o：在函数‘google::protobuf::internal::FunctionClosure0::FunctionClosure0(void (*)(), bool)’中：
/usr/include/google/protobuf/stubs/common.h:871：对‘vtable for google::protobuf::internal::FunctionClosure0’未定义的引用
person.pb.o：在函数‘google::protobuf::GoogleOnceInit(long*, void (*)())’中：
/usr/include/google/protobuf/stubs/once.h:127：对‘google::protobuf::GoogleOnceInitImpl(long*, google::protobuf::Closure*)’未定义的引用
/usr/include/google/protobuf/stubs/once.h:126：对‘google::protobuf::internal::FunctionClosure0::~FunctionClosure0()’未定义的引用
/usr/include/google/protobuf/stubs/once.h:126：对‘google::protobuf::internal::FunctionClosure0::~FunctionClosure0()’未定义的引用
person.pb.o：在函数‘google::protobuf::internal::GetEmptyString[abi:cxx11]()’中：
/usr/include/google/protobuf/generated_message_util.h:84：对‘google::protobuf::internal::InitEmptyString()’未定义的引用
/usr/include/google/protobuf/generated_message_util.h:84：对‘google::protobuf::internal::empty_string_once_init_’未定义的引用
person.pb.o：在函数‘google::protobuf::MessageLite::MessageLite()’中：
/usr/include/google/protobuf/message_lite.h:79：对‘vtable for google::protobuf::MessageLite’未定义的引用
person.pb.o：在函数‘google::protobuf::Message::Message()’中：
/usr/include/google/protobuf/message.h:167：对‘vtable for google::protobuf::Message’未定义的引用
person.pb.o：在函数‘google::protobuf::UnknownFieldSet::Clear()’中：
/usr/include/google/protobuf/unknown_field_set.h:226：对‘google::protobuf::UnknownFieldSet::ClearFallback()’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedInputStream::ReadVarint32(unsigned int*)’中：
/usr/include/google/protobuf/io/coded_stream.h:799：对‘google::protobuf::io::CodedInputStream::ReadVarint32Fallback(unsigned int*)’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedOutputStream::WriteVarint32ToArray(unsigned int, unsigned char*)’中：
/usr/include/google/protobuf/io/coded_stream.h:1015：对‘google::protobuf::io::CodedOutputStream::WriteVarint32FallbackToArray(unsigned int, unsigned char*)’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedOutputStream::WriteVarint32SignExtendedToArray(int, unsigned char*)’中：
/usr/include/google/protobuf/io/coded_stream.h:1030：对‘google::protobuf::io::CodedOutputStream::WriteVarint64ToArray(unsigned long, unsigned char*)’未定义的引用
person.pb.o：在函数‘google::protobuf::io::CodedOutputStream::VarintSize32(unsigned int)’中：
Makefile:245: recipe for target '1102test_proto' failed
/usr/include/google/protobuf/io/coded_stream.h:1091：对‘google::protobuf::io::CodedOutputStream::VarintSize32Fallback(unsigned int)’未定义的引用
person.pb.o：在函数‘google::protobuf::internal::WireFormat::VerifyUTF8StringNamedField(char const*, int, google::protobuf::internal::WireFormat::Operation, char const*)’中：
/usr/include/google/protobuf/wire_format.h:327：对‘google::protobuf::internal::WireFormat::VerifyUTF8StringFallback(char const*, int, google::protobuf::internal::WireFormat::Operation, char const*)’未定义的引用
person.pb.o：在函数‘Test::Person const* google::protobuf::internal::dynamic_cast_if_available<Test::Person const*, google::protobuf::Message const*>(google::protobuf::Message const*)’中：
/usr/include/google/protobuf/generated_message_reflection.h:496：对‘typeinfo for google::protobuf::Message’未定义的引用
person.pb.o:(.data.rel.ro._ZTVN4Test6PersonE[_ZTVN4Test6PersonE]+0x20)：对‘google::protobuf::Message::GetTypeName[abi:cxx11]() const’未定义的引用
person.pb.o:(.data.rel.ro._ZTVN4Test6PersonE[_ZTVN4Test6PersonE]+0x40)：对‘google::protobuf::Message::InitializationErrorString[abi:cxx11]() const’未定义的引用
person.pb.o:(.data.rel.ro._ZTVN4Test6PersonE[_ZTVN4Test6PersonE]+0x48)：对‘google::protobuf::Message::CheckTypeAndMergeFrom(google::protobuf::MessageLite const&)’未定义的引用
person.pb.o:(.data.rel.ro._ZTVN4Test6PersonE[_ZTVN4Test6PersonE]+0x88)：对‘google::protobuf::Message::DiscardUnknownFields()’未定义的引用
person.pb.o:(.data.rel.ro._ZTVN4Test6PersonE[_ZTVN4Test6PersonE]+0x90)：对‘google::protobuf::Message::SpaceUsed() const’未定义的引用
person.pb.o:(.data.rel.ro._ZTIN4Test6PersonE[_ZTIN4Test6PersonE]+0x10)：对‘typeinfo for google::protobuf::Message’未定义的引用
collect2: error: ld returned 1 exit status
make: *** [1102test_proto] Error 1
17:01:43: 进程"/usr/bin/make"退出，退出代码 2 。
Error while building/deploying project 1102test_proto (kit: Desktop Qt 5.9.1 GCC 64bit)
When executing step "Make"
17:01:43: Elapsed time: 00:00.https://www.cnblogs.com/gongxijun/p/8981086.html //跑成功了
这篇博客是自己定义了一个demo.proto，描述了数据格式：
文件名字：//demo.proto
package caffe;
message Student
{
required int32 age = 1; //ID required 表示必要字段
required string name = 2; //str 必要字段
optional int32 grade = 3 ; //optional field 可选字段，可以有无，最多ｂ
}
message WorkDay{
required bool isworker =1;
required bool isjiaban =2; //是否算加班
}
message Teacher{
required string name = 1 ;
required WorkDay work = 2; //是否工作
optional int32 age = 3;
}
//班级
message Class{
required string name = 1; //班级名称
repeated Student stu = 2; //班级成员 数组
repeated Teacher teacher=3;
}然后我们敲命令编译：
/usr/bin$ ./protoc -I=/media/d_2/everyday/1102/protoc/proto --cpp_out=/media/d_2/everyday/1102/protoc/my_out /media/d_2/everyday/1102/protoc/proto/demo.proto
会在my_out文件夹里面生成两个文件demo.pb.cc和demo.pb.h
作者提供了类似网络的prototxt
name: "三年级23班"
teacher {
name: "tom"
age: 17
work {
isworker: 1 ;#中文
isjiaban: 1;
}
}
stu {
age: 19;
name: "demo"; ##中文
grade: 134;
}
stu {
age: 19;
name: "google"; ##中文
grade: 134;
}
stu {
age: 19;
name: "snake"; ##中文
grade: 134;
}新建QT工程加载demo.pb.cc和demo.pb.h：main函数如下：
//
// Created by xijun1 on 2017/12/22.
//
#include <google/protobuf/io/coded_stream.h>
#include <google/protobuf/io/zero_copy_stream_impl.h>
#include <google/protobuf/text_format.h>
//反射机制
//#include <google/protobuf/compiler/importer.h>
#include <google/protobuf/dynamic_message.h>
#include "demo.pb.h"
#include<iostream>
#include <fstream>
#include<ios>
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <fcntl.h> // open
using namespace std;
void InfoStudents(const caffe::Student & stu){
cout<< "student info:"<<endl;
cout<<" name: "<<stu.name()<<endl;
cout<<" age: "<<stu.age()<<endl;
cout<<" grade: "<<stu.grade()<<endl;
}
void InfoTeacher(const caffe::Teacher & teacher) {
cout << "teacher info:" << endl;
cout << " name: " << teacher.name() << endl;
cout << " age: " << teacher.age() << endl;
cout<< " is worker: "<<teacher.work().isworker()<<endl;
cout<< " is jiaban: "<<teacher.work().isjiaban()<<endl;
}
int main(void)
{
caffe::Class cls;
int file_desc = open("/media/d_2/everyday/1102/protoc/param.prototxt",O_NDELAY);
google::protobuf::io::FileInputStream fileInputStream(file_desc);
if(!google::protobuf::TextFormat::Parse(&fileInputStream,&cls)){
std::cout<<"parse failure."<<std::endl;
return -1;
}
std::cout<<cls.name()<<std::endl;
//按照索引进行读取
for(int i=1;i<cls.GetMetadata().descriptor->field_count(); ++i){
std::cout<<cls.descriptor()->field(i)->name()<<std::endl;
//cout<<cls.descriptor()->field(i)->full_name()<<endl;
if(cls.descriptor()->field(i)->name()=="stu"){
for (auto &stu_info : cls.stu()){
InfoStudents(stu_info);
}
}
if(cls.descriptor()->field(i)->name()=="teacher"){
for (auto &teacher_info : cls.teacher()){
InfoTeacher(teacher_info);
}
}
}
return 0;
}
终端输出如下：
三年级23班
stu
student info:
name: demo
age: 19
grade: 134
student info:
name: google
age: 19
grade: 134
student info:
name: snake
age: 19
grade: 134
teacher
teacher info:
name: tom
age: 17
is worker: 1
is jiaban: 1
按 <RETURN> 来关闭窗口...
工程文件压缩包：https://download.csdn.net/download/yang332233/10765029
下一步读这个博客：https://blog.csdn.net/qiusuoxiaozi/article/details/61199892