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Gostaria de aguardar o final da execução do processo (calc.exe), mas não funciona. Meu programa termina rápido / agora enquanto meu processo (calc.exe) continua em execução (não o interrompi

e WaitForSingleObject retorna imediatamente WAIT_OBJECT_0.

ps: desabilitei meu antivírus de software (AVIRA)

int main(int argc, char** arv)
{
STARTUPINFO si;
PROCESS_INFORMATION pi;

ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));

const char * calcPrgm = "C:\\\\Windows\\System32\\calc.exe";
LPSTR calcPrgmLpstr = const_cast<LPSTR>(calcPrgm);

// Start the child process. 
if (!CreateProcess(NULL,   // No module name (use command line)
    calcPrgmLpstr,        // Command line
    NULL,           // Process handle not inheritable
    NULL,           // Thread handle not inheritable
    FALSE,          // Set handle inheritance to FALSE
    0,              // No creation flags
    NULL,           // Use parent's environment block
    NULL,           // Use parent's starting directory 
    &si,            // Pointer to STARTUPINFO structure
    &pi)           // Pointer to PROCESS_INFORMATION structure
    )
{
    printf("CreateProcess failed (%d).\n", GetLastError());
    return -1;
}

// Wait until child process exits.
auto ret = WaitForSingleObject(pi.hProcess, INFINITE);
printf("WaitForSingleObject ret = %x\n", ret);
if (ret == WAIT_OBJECT_0)
{
    printf("WaitForSingleObject ret ret == WAIT_OBJECT_0\n");
}
BOOL b = FALSE;
DWORD n = 0;
b = GetExitCodeProcess(pi.hProcess, &n);

// Close process and thread handles. 
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
printf("WaitForSingleObject end\n");
return 0;
}