Two ideas for Python to obtain the char* field returned in C++

Sometimes I need to get the uncertain length char* string returned in C++ functions. At present, I have found two ideas to solve the problem, and the specific implementation is as follows:

1. Put char* into the structure

The c++ function is as follows:

typedef struct FileData {
        long long lenth;
        char* data;
};
 
bool GetData(FileData *data)
{
    if (data == nullptr) {
        return false;
    }
    data->data = new char[255];
    memset(data->data, 0, 255);
    const char* laosi = "wdaweqweqweqweqweqweqweqwdvdggggsdfsferqwerawerqwerqwerqerqwedsd";
    memcpy(data->data, laosi, strlen(laosi));
    data->lenth = strlen(laosi);
    return true;
}

The python code is as follows:

import ctypes
import os
import platform
from threading import Thread,Lock
 
CharPtr = (ctypes.c_char)
class FileData():
    _fields_=[
        ("lenth",ctypes.c_longlong),
        ("data",CharPtr)
    ]
 
FileDataPtr = (FileData)
 
def GetDll():
    if ().lower() == 'windows':
        isWinPlat_ = True
    else:
        isWinPlat_ = False
    currentPath_ = ().replace('\\','/') 
    if isWinPlat_:
        dll_ = (currentPath_ + '/')
    else:
        dll_ = (currentPath_ + '/')
    return dll_
 
pytestdll_ = GetDll()
 
def GetData():
    getDataF = pytestdll_.GetData
    =[FileDataPtr]
     = ctypes.c_bool
 
    dataa = FileData()
    ret = getDataF((dataa))
    print()
    len = 
    for i in range(len):
        print([i])
 
    charArr = ctypes.c_char*
    char_arr = charArr(*[:])
    print(char_arr.raw)
 
    return ret
 
GetData()

2. Use char* as the return value

The c++ code is as follows:

char* GetDatas(long long& lenth)
{
    char* data = new char[255];
    memset(data, 0, 255);
    const char* laosi = "wdaweqweqweqweqweqweqweqwdvdggggsdfsferqwerawerqwerqwerqerqwedsd";
    memcpy(data, laosi, strlen(laosi));
    lenth = strlen(laosi);
    return data;
}

The python code is as follows:

import ctypes
import os
import platform
from threading import Thread,Lock
 
CharPtr = (ctypes.c_char)
class FileData():
    _fields_=[
        ("lenth",ctypes.c_longlong),
        ("data",CharPtr)
    ]
 
FileDataPtr = (FileData)
 
def GetDll():
    if ().lower() == 'windows':
        isWinPlat_ = True
    else:
        isWinPlat_ = False
    currentPath_ = ().replace('\\','/') 
    if isWinPlat_:
        dll_ = (currentPath_ + '/')
    else:
        dll_ = (currentPath_ + '/')
    return dll_
 
pytestdll_ = GetDll()
 
def GetDataS():
    getDatasF = pytestdll_.GetDatas
    =[(ctypes.c_longlong)]
     = ctypes.c_char_p
    lengths = ctypes.c_longlong(0)
    ret = getDatasF((lengths))
    print()
    print(ret)
GetDataS()

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