Thank you very much ChrisW67! It works.

Perhaps I still misunderstand something, but that's an option for some reason just does not work, cookies Mortal = 1
Qt Code: 
  1. #include <QtCore>
  2. #include <QApplication>
  3. #include <QDebug>
  4. #include <QtNetwork>
  5.  
  6. class MyCookieJar : public QNetworkCookieJar
  7. {
  8. public:
  9.     QList<QNetworkCookie> getAllCookies() { return allCookies(); }
  10. };
  11.  
  12.  
  13. class CookiesTest : public QObject
  14. {
  15. Q_OBJECT
  16. public:
  17.     CookiesTest(QWidget* parent = 0);
  18.     void download(QString);
  19.  
  20. private slots:
  21.     void replyFinished(QNetworkReply*);
  22.     void doAnother();
  23.  
  24. private:
  25.     QNetworkAccessManager* manager;
  26.     MyCookieJar *cookieJar;
  27.     QUrl myUrl;
  28. };
  29.  
  30. CookiesTest::CookiesTest(QWidget* parent)
  31. {
  32.     manager = new QNetworkAccessManager;
  33.     cookieJar = new MyCookieJar;
  34.     manager->setCookieJar(cookieJar);
  35.  
  36.     connect(manager, SIGNAL(finished(QNetworkReply*)), this, SLOT(replyFinished(QNetworkReply*)));
  37. }
  38.  
  39. void CookiesTest::replyFinished(QNetworkReply* reply)
  40. {
  41.     qDebug() << reply->readAll();
  42.     qDebug() << "getAllCookies: " << cookieJar->getAllCookies();
  43. }
  44.  
  45. void CookiesTest::doAnother() {
  46.     manager->get(QNetworkRequest(myUrl));
  47. }
  48.  
  49. void CookiesTest::download(QString url)
  50. {
  51.     myUrl = QUrl(url);
  52.     QTimer::singleShot(500, this, SLOT(doAnother()));
  53. }
  54.  
  55. int main(int argc, char* argv[])
  56. {
  57.     QApplication app(argc, argv);
  58.     CookiesTest cookiesTest;
  59.     cookiesTest.download("http://test1.ru/test/cookie.php");
  60.     cookiesTest.download("http://test1.ru/test/cookie.php");
  61.     return app.exec();
  62. }
  63.  
  64. #include "main.moc"
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Output:
"NUM: []"
getAllCookies: (QNetworkCookie("Mortal=1; expires=Wed, 18-Jul-2029 05:49:51 GMT; domain=test1.ru; path=/test/") )
"NUM: []"
getAllCookies: (QNetworkCookie("Mortal=1; expires=Wed, 18-Jul-2029 05:49:51 GMT; domain=test1.ru; path=/test/") )

But I found another solution to this

Qt Code: 
  1. #include <QtCore>
  2. #include <QApplication>
  3. #include <QDebug>
  4. #include <QtNetwork>
  5.  
  6.  
  7. class MyCookieJar : public QNetworkCookieJar
  8. {
  9. public:
  10.     QList<QNetworkCookie> getAllCookies() { return allCookies(); }
  11. };
  12.  
  13.  
  14. class CookiesTest : public QObject
  15. {
  16.     Q_OBJECT
  17. public:
  18.     CookiesTest(QObject *parent = 0);
  19.     void download(QString);
  20.     void _download(QUrl);
  21.  
  22. private:
  23.     QNetworkAccessManager* manager;
  24.     MyCookieJar *cookieJar;
  25.     QList<QNetworkCookie> cookiesList;
  26. };
  27.  
  28. CookiesTest::CookiesTest(QObject *parent) : QObject(parent)
  29. {
  30.     manager = new QNetworkAccessManager;
  31.     cookieJar = new MyCookieJar();
  32.     manager->setCookieJar(cookieJar);
  33. }
  34.  
  35. void CookiesTest::download(QString url)
  36. {
  37.     _download(QUrl(url));
  38. }
  39.  
  40. void CookiesTest::_download(QUrl url)
  41. {
  42.     //enters event loop, simulate blocking io
  44.     QTimer t;
  45.     t.setSingleShot(true);
  46.     connect(&t, SIGNAL(timeout()), &q, SLOT(quit()));
  47.  
  48.     QNetworkReply *reply = manager->get(QNetworkRequest(url));
  49.     connect(reply, SIGNAL(finished()), &q, SLOT(quit()));
  50.  
  51.     t.start(5000);
  52.     q.exec();
  53.  
  54.     if (t.isActive()) {
  55.         t.stop();
  56.         QByteArray response = reply->readAll();
  57.         qDebug() << response;
  58.  
  59.         QVariant redirectionTarget = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
  60.         if (reply->error()) {
  61.             qDebug()<< "Download failed" <<  reply->errorString();
  62.         } else if (!redirectionTarget.isNull()) {
  63.             QUrl newUrl = url.resolved(redirectionTarget.toUrl());
  64.             qDebug()<< "Redirect to" <<  newUrl.toString();
  65.             url = newUrl;
  66.             // reply->deleteLater();
  67.             _download(url);
  68.         } else {
  69.             qDebug() << "Finish! ";
  70.         }
  71.  
  72.         reply->deleteLater();
  73.  
  74.     } else {
  75.         qDebug() << "Timeout";
  76.     }
  77.  
  78.     cookiesList = cookieJar->getAllCookies();
  79.     qDebug() << "getAllCookies: " << cookiesList;
  80. }
  81.  
  82. int main(int argc, char* argv[])
  83. {
  84.     QApplication app(argc, argv);
  85.     CookiesTest cookiesTest;
  86.     cookiesTest.download("http://test1.ru/test/cookie.php");
  87.     cookiesTest.download("http://test1.ru/test/cookie.php");
  88.     cookiesTest.download("http://test1.ru/test/cookie.php");
  89.     return app.exec();
  90. }
  91.  
  92. #include "main.moc"
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Output:
"NUM: []"
Finish!
getAllCookies: (QNetworkCookie("Mortal=1; expires=Wed, 18-Jul-2029 05:49:51 GMT; domain=test1.ru; path=/test/") )
"NUM: [1]"
Finish!
getAllCookies: (QNetworkCookie("Mortal=2; expires=Wed, 18-Jul-2029 05:49:51 GMT; domain=test1.ru; path=/test/") )
"NUM: [2]"
Finish!
getAllCookies: (QNetworkCookie("Mortal=3; expires=Wed, 18-Jul-2029 05:49:51 GMT; domain=test1.ru; path=/test/") )