用C和C++从父进程中获取子进程列表(跨平台，无命令行)

#ifdef _WIN32
#include <windows.h>
#include <tlhelp32.h>
#else
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#endif

#include <iostream>
#include <vector>

#ifdef _WIN32
std::vector<DWORD> GetChildProcesses(DWORD parentProcessId) {
    std::vector<DWORD> childProcesses;

    HANDLE hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
    if (hSnapshot != INVALID_HANDLE_VALUE) {
        PROCESSENTRY32 pe32;
        pe32.dwSize = sizeof(PROCESSENTRY32);

        if (Process32First(hSnapshot, &pe32)) {
            do {
                if (pe32.th32ParentProcessID == parentProcessId) {
                    childProcesses.push_back(pe32.th32ProcessID);
                }
            } while (Process32Next(hSnapshot, &pe32));
        }

        CloseHandle(hSnapshot);
    }

    return childProcesses;
}
#else
std::vector<pid_t> GetChildProcesses(pid_t parentProcessId) {
    std::vector<pid_t> childProcesses;

    FILE* fp = popen("ps -eo pid,ppid", "r");
    if (fp != nullptr) {
        char line[256];
        fgets(line, sizeof(line), fp); // Skip the header line

        while (fgets(line, sizeof(line), fp) != nullptr) {
            pid_t pid, ppid;
            sscanf(line, "%d %d", &pid, &ppid);

            if (ppid == parentProcessId) {
                childProcesses.push_back(pid);
            }
        }

        pclose(fp);
    }

    return childProcesses;
}
#endif

int main() {
    pid_t parentProcessId = getpid();

#ifdef _WIN32
    std::vector<DWORD> childProcesses = GetChildProcesses(parentProcessId);
#else
    std::vector<pid_t> childProcesses = GetChildProcesses(parentProcessId);
#endif

    std::cout << "Child Processes:" << std::endl;
    for (const auto& childProcess : childProcesses) {
        std::cout << childProcess << std::endl;
    }

    return 0;
}