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QNetworkAccessManager - How to disable HELP command. (FTP)

  • Hi,

    QT 5.4
    Windows 7

    The HELP command gets called from my QT application every single time after a file gets downloaded, or in this case after it has logged in. (WIreshark image below)

    I've based my application on the Network Download Manager Example. (Which also calls the FTP HELP command)

    I'm trying to find a way to disable calling the HELP command but no luck.

    I'm doing this to reduce as much traffic as possible on my FTP server.

    I've noticed that when you download a file in qt4 using QFTP it does not call the HELP command.

    If it can't be disabled I believe I might be able to configure my FTP to reject HELP commands and return a 501 but I would rather find a better solution.

    alt text

    Thank you for your help.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    I can't answer directly to your question however, QFTP has been made usable with Qt 5 also if you'd like to continue using it.

  • @SGaist


    Thanks for the reply but unfortunately I'm not in a position to use obsolete classes. (Not my call to make unfortunately)


  • Lifetime Qt Champion

    You should then check the QFtp class in Qt's sources. Note that you are using a relatively old version of Qt. If possible you should update if not the latest at least 5.6 which is LTS.

  • I've managed a work around.

    You can view the link below with the changes I've made to the source code.

    If the modifications don't get implemented it is possible to stop sending HELP requests without breaking everything. If you need any help implementing the changes please message me!

    I will mark this as solved.

  • One last question. As I've modified the Qt source code do I have to submit the changes to Qt?

  • Lifetime Qt Champion

    You have to make them available to your customer.

    Note that every improvement you can provide will be appreciated and made available to all Qt users so it would be nice considering doing a submission.

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