项目中需要单片机上位机和 javaweb 通信，上位机C语言编程，用到protobuf-C。
参考文章【按照参考价值从大到小排列】
https://www.linuxidc.com/Linux/2016-12/138716.htm
http://blog.chinaunix.net/uid-31343710-id-5757256.html
https://github.com/protobuf-c/protobuf-c/wiki/Examples
https://blog.csdn.net/ZHONGCAI0901/article/details/86608029
下面是安装过程中使用到的命令和相关说明：
我的安装目录：/usr/protobuf/install
yum install autoconf
yum install automake
yum install libtool
yum install curl (used to download gmock)
yum install make
yum install g++
cd /usr/protobuf
tar zxvf protobuf-all-3.7.0.tar.gz
tar zxvf protobuf-c-1.3.1.tar.gz
cd protobuf-3.7.0
./configure --prefix=/usr/protobuf/install
make
----make check
----make install
vim /etc/profile
#protobuf
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/protobuf/install/lib
export LIBRARY_PATH=$LIBRARY_PATH:/usr/protobuf/install/lib
export PATH=$PATH:/usr/protobuf/install/bin
source /etc/profile
protoc --version
=============================================================
cd protobuf-c-1.3.1
export PKG_CONFIG_PATH=/usr/protobuf/install/lib/pkgconfig
./configure --prefix=/usr/protobuf/install
make 出现错误 和 警告
CXX t/generated-code2/cxx_generate_packed_data-cxx-generate-packed-data.o
t/generated-code2/cxx-generate-packed-data.cc: In function ‘void dump_test_unknown_fields()’:
t/generated-code2/cxx-generate-packed-data.cc:1001:9: error: ‘Reflection’ in ‘class google::protobuf::Message’ does not name a type
cd /usr/protobuf/protobuf-c-1.3.1/t/generated-code2
vim cxx-generate-packed-data.cc
删除上面这一行，增加下面那一行
const google::protobuf::Message::Reflection *reflection = mess.GetReflection();
const google::protobuf::Reflection *reflection = mess.GetReflection();
----make check 出现警告忽略
----make install
protoc-c
===========================================================
cd /usr/protobuf/proto
protoc-c --c_out=./ message.proto
=====================================
win
protoc ./message.proto --java_out=./
=======================
编码：
1、头文件 ：#include 修改成 #include “protobuf-c.h”
2、头文件 ：struct 之前加上 typedef