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Help Files for Standard Libs

  • 2 weeks Linux. Some Things great, really great. But to change to Linux I have to find a solution for the developement enviroment. This is the top discipline of Microsoft. I don't know any better developement enviroment. The QTCreator want be an alternative and ... ok, something is pain in the arse, but acceptable. But two Features very important for me. Maybe, someone knows help.

    The help system works only with QT Stuff. For example. A Function in Linux works different from Windows. The access to the Hard Disks. So I Searched the functionality in internet and found:

    int fd;

    if((fd = open("/dev/hda", O_RDONLY | O_NONBLOCK)) < 0)
    if((fd = open("/dev/sda", O_RDONLY | O_NONBLOCK)) < 0)
    return NULL;

    I want know all, always. So I want help about the open function, especially the first parameter. But if I use F1 over the open() Function I get a small Selection Window about many open from QT Classes, but not from Standard Libraries. I have to go in Internet and search with duckduckgo. Then I inspect some sites until I found the information. That pain in the arse. There are some qch-Files to download outside the qt World ?

    The second is the source browser system. This is one of the top goals of Visual Studio. If the Cursor is over the open() Function I press right mouse button (better is F12) and select "go to declaration". The Source browser opens the Header File with declaration. This functionality is essential for me. I use ist nearly 20 years for inspect source code. I work often with "problem" sources. And if I want a fast overview I have to find the declares fast. Oops, during I write this message I try "Follow Symbol under Cursor". Great, exactly what I need. OK, the second problem is solved.

  • Lifetime Qt Champion

    @TomBombadill said in Help Files for Standard Libs:

    I have to go in Internet and search with duckduckgo

    The UNIX way to get information are man pages. Enter

    man 2 open

    in a terminal.

    man man

  • @TomBombadill
    As a general observation about programming with Qt. Although it is possible you may need to go down to man 2 open to achieve what you want, a large part of the point of using Qt is to use Qt's own platform-independent calls instead of platform-specific ones. Why did you feel you needed to use the Linux fd = open() calls here when e.g. QFile::open(QIODevice::ReadOnly | QIODevice::Unbuffered), or other methods of QFile::open(), is available?

    I do understand in this case you are opening a device-specific path, and I don't know what exactly you do with fd after this which may all be Linux-specific, it is just an observation.

  • Lifetime Qt Champion

    Hi @TomBombadill,

    you can register additional documentation in Qt Creator, have a look here:


  • jsulm: I'm surprised that the "man" Command works for Developers stuff. I work only since 2 weeks with Linux. I think it is not the last suprise and the last difference to Windows. Thanks.

    JonB: You wonder that I'm not use QFile::open(). In this case, because I don't know that I can use. And the second time because I need Information about the Hard Disks. But anyway, I like Qt, but sometimes I use other Libs, especially if another Standard involved. For example. I never use the Qt Container Classes QList, QVector a.s.o. . But in this case I dont' know that I can use QFile. Thanks for your help.

    aha_1980: Thanks, you can be sure that I use this Link immediately after I reply.

    And sorry, maybe one Question more. Where I can get a list for information in wich Paket is which File. In moment I write the control file for deployment and want find out the dependencies. My project use a lot of dependencies. If I search like "libstdc++ which paket" the information not clear. Sure I can look to the properties and see the Filename With this information I can combine "Depends: libstdc++6 (>=6.0.25)". But my list is long (32 Dependencies). Is there a list (in internet or wherever) where I can find wich package I need for wich Dependency ?

  • Lifetime Qt Champion

    @TomBombadill said in Help Files for Standard Libs:

    where I can find wich package I need for wich Dependency

    Depends on the Linux distribution you're using.
    If you use a Linux distribution which uses apt you can check

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