https://blog.csdn.net/zhaojunwuiris/article/details/85773294
https://www.cnblogs.com/fengbohello/p/4059435.html

python
rm /usr/bin/python
#删除之前的python2的软连接
ln -s /usr/local/python3/bin/python3.7 /usr/bin/python
#新建一个软连接到python修改默认版本python和yum

error while loading shared libraries: libjson.so: cannot open shared object file: No such file or directory

[root@instance-sutadosy moleserver]# ./testjson 
./testjson: error while loading shared libraries: libjson.so: cannot open shared object file: No such file or directory
[root@instance-sutadosy moleserver]# ld
ld        ldattach  ld.bfd    ldconfig  ldd       ld.gold   
[root@instance-sutadosy moleserver]# ldconfig 
[root@instance-sutadosy moleserver]# ./testjson 
json
jsoncpp
{
   "array" : [
      {
         "cpp" : "jsoncpp",
         "java" : "jsoninjava",
         "php" : "support"
      }
   ],
   "name" : "json"
}

/*
g++ testjson.cpp -o testjson -ljson
*/

#include <iostream>
#include <string>
#include <jsoncpp/json/json.h>

void readJson();
void writeJson();

int main(int argc, char** argv) {
    readJson();
    writeJson();
    return 0;
}

void readJson() {
    using namespace std;
    std::string strValue = "{\"name\":\"json\",\"array\":[{\"cpp\":\"jsoncpp\"},{\"java\":\"jsoninjava\"},{\"php\":\"support\"}]}";

    Json::Reader reader;
    Json::Value value;

    if (reader.parse(strValue, value))
    {
        std::string out = value["name"].asString();
        std::cout << out << std::endl;
        const Json::Value arrayObj = value["array"];
        for (unsigned int i = 0; i < arrayObj.size(); i++)
        {
            if (!arrayObj[i].isMember("cpp"))
                continue;
            out = arrayObj[i]["cpp"].asString();
            std::cout << out;
            if (i != (arrayObj.size() - 1))
                std::cout << std::endl;
        }
    }
}

void writeJson() {
    using namespace std;

    Json::Value root;
    Json::Value arrayObj;
    Json::Value item;

    item["cpp"] = "jsoncpp";
    item["java"] = "jsoninjava";
    item["php"] = "support";
    arrayObj.append(item);

    root["name"] = "json";
    root["array"] = arrayObj;

    root.toStyledString();
    std::string out = root.toStyledString();
    std::cout << out << std::endl;
}