如何使用POSIX执行命令并在C++中获取命令输出？

#include<iostream>
#include<stdio.h>
#include<string>

int main() {
    std::string command = "ls";
    FILE *stream = popen(command.c_str(), "r");

    if (stream) {
        char buffer[128];
        while (fgets(buffer, sizeof(buffer), stream) != NULL) {
            std::cout<< buffer;
        }
        pclose(stream);
    }

    return 0;
}