source: trunk/doc/src/platforms/platform-notes-rtos.qdoc

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/*!
    \page platform-notes-vxworks.html
    \title Platform and Compiler Notes - VxWorks
    \contentspage Platform and Compiler Notes
    \target VxWorks

    \note VxWorks is a community supported platform. See the
    \l{Supported Platforms} page for more information.

    This page contains information about the Qt for VxWorks port. More
    information about the combinations of platforms and compilers supported
    by Qt can be found on the \l{Supported Platforms} page.

    \tableofcontents

    \section1 Supported Versions

    Qt has been tested on WindRiver VxWorks 6.7 in kernel mode using the
    vendor supplied GCC compiler, targetting both the x86 simulator
    (simpentium) and Power-PC devices (ppc).
    VxWorks' RTP mode is currently not supported.

    \section1 Limitations

    The VxWorks kernel has an optional POSIX compatibility layer, but this
    layer does not implement all POSIX functionality needed for a complete
    Qt port.

    \table
    \header \o Function \o Notes
    \row \o QProcess
         \o Not available - VxWorks has no concept of processes.
    \row \o QSharedMemory
         \o Not available - VxWorks has only a global, flat address space.
    \row \o QSystemSemaphore
         \o Not available - VxWorks has no concept of processes.
    \row \o QLibrary
         \o QLibrary is only a small stub to make it possible to build
            static plugins.
    \row \o QCoreApplication
         \o Can only be instantiated once. Qt's Q(CoreE)Application is
            tightly coupled to one address space and process, while VxWorks
            only supports one global address space and has no concept of
            processes.
    \row \o Phonon
         \o There is no standard audio backend, which could be integrated into Phonon.
    \row \o Qt3Support
         \o The Qt3Support library is not available on VxWorks.

    \endtable

    \section1 Build Instructions

    Qt for VxWorks needs to be \l{Cross-Compiling Qt for Embedded Linux
    Applications}{cross-compiled} on a Linux host.  \c configure and \c make
    the build like you would with a standard \l{Cross-Compiling Qt for
    Embedded Linux Applications}{embedded Linux cross build}.  Building the
    VxWorks simulator would be done like this:

    \code
    <path/to/qt/sources>/configure -xplatform unsupported/vxworks-simpentium-g++ -embedded vxworks -exceptions -no-gfx-linuxfb -no-mouse-linuxtp -no-mouse-pc -no-kbd-tty
    make
    \endcode

    \list
    \o \c{-xplatform unsupported/qws/vxworks-simpentium-g++} - selects the x86 simulator mkspec for VxWorks
    \o \c{-embedded vxworks} - builds the embedded version of Qt and sets the architecture to VxWorks
    \o \c{-exceptions} - see General Notes below
    \o \c{-no-gfx-linuxfb}, \c{-no-mouse-linuxtp}, \c{-no-mouse-pc} and \c{-no-kbd-tty} are Linux specific and won't work on VxWorks
    \endlist

    \section1 General Notes

    \list

    \o Configuring with \c{-exceptions} is necessary, because the VxWorks
    6.7 g++ headers require exceptions to be enabled when compiling C++
    code.

    \o Configure's \c{-xplatform} can be any of
    \c{unsupported/vxworks-(simpentium|ppc)-(g++|dcc)}, but \c{dcc}
    (WindRiver DIAB compiler) has not yet tested been tested with Qt 4.6 and
    VxWorks 6.7.

    \o Building shared libraries with \c{-shared} (the default) doesn't
    really build shared libraries, like e.g.  on Linux, since these are not
    supported by VxWorks.  Instead, qmake will created partially linked
    objects, that can be loaded at runtime with \c{ld}.

    \o Creating static builds with \c{-static} is fully supported.

    \o "Munching" (generating constructors/destructors for static C++
    objects) is done automatically by a special qmake extension (for both
    shared libraries and executables)

    \o VxWorks does not have a file system layer, but the low level storage
    drivers have to supply a file system like interface to the applications.
    Since each driver implements a different subset of the functionality
    supported by this interface, Qt's file system auto-tests show wildly
    differing results running on different "file systems".  The best results
    can be achieved when running on a (writable) NFS mount, since that
    provides the most Unix-ish interface.  The worst results come from the
    FTP file system driver, which may crash when accessed by a
    \c{QFileInfo}.

    \o Keep in mind that VxWorks doesn't call your \c{main()} function with
    the standard \c{argc}/\c{argv} parameters.  So either add a special
    \c{vxmain()} function or use a tool like \c{callmain} to translate
    VxWorks' commandline arguments to an \c{argc}/\c{argv} array.

    \o Some example will fail to build, due to some missing dependencies
    (e.g. shared memory) - this will be fixed in a later release.

    \endlist
*/

/*!
    \page platform-notes-qnx.html
    \title Platform and Compiler Notes - QNX
    \contentspage Platform and Compiler Notes
    \target QNX

    \note QNX is a community supported platform. See the
    \l{Supported Platforms} page for more information.

    This page contains information about the Qt for QNX port. More
    information about the combinations of platforms and compilers supported
    by Qt can be found on the \l{Supported Platforms} page.

    Note that Qt for QNX is currently based on \l{Qt for Embedded Linux}, which
    contains its own windowing system. Mixing QNX's Photon environment with
    Qt for QNX is currently not possible. Building Qt for QNX with Photon's
    X11 embedded server is not recommended due to missing support for X11 extensions,
    resulting in poor rendering quality.

    Qt for QNX contains experimental screen and input drivers based on QNX's
    \c devi-hid and \c io-display. For more information, check the class documentation
    for QQnxScreen, QWSQnxKeyboardHandler and QQnxMouseHandler. See the
    \l{Porting Qt for Embedded Linux to a New Architecture} document for information
    on how to add custom screen or input drivers.

    \tableofcontents

    \section1 Supported Versions

    Qt has been tested on QNX 6.4 on i386 and PowerPC targets with QNX's default
    gcc compiler.

    \section1 Limitations

    Some of Qt's functionality is currently not available on QNX:

    \table
    \header \o Function \o Notes
    \row \o QProcess
         \o Not available - QNX doesn't support mixing threads and processes.
    \row \o QSharedMemory
         \o Not available - QNX doesn't support SYSV style shared memory.
    \row \o QSystemSemaphore
         \o Not available - QNX doesn't support SYSV style system semaphores.
    \row \o QWS Multi Process
         \o QT_NO_QWS_MULTIPROCESS is always on due to missing shared memory support.
    \row \o Phonon
         \o There is no standard audio backend, which could be integrated into Phonon.
    \row \o Qt3Support
         \o The Qt3Support library is not available on QNX.
    \endtable

    \section1 Build Instructions

    Qt for QNX needs to be built either on a QNX system, or \l{Cross-Compiling Qt
    for Embedded Linux Applications}{cross-compiled} on a Linux host. In either
    case, The QNX Software Development Platform must be installed.

    Example configure line for cross-compiling Qt for QNX on a Linux host for an
    i386 QNX target:

    \code
    configure -xplatform unsupported/qws/qnx-i386-g++ -embedded i386 -no-gfx-linuxfb -no-mouse-linuxtp -no-kbd-tty -no-qt3support -qt-gfx-qnx -qt-mouse-qnx -qt-kbd-qnx -no-exceptions
    \endcode

    \list
    \o \c{-xplatform unsupported/qws/qnx-i386-g++} - selects the i386-g++ mkspec for QNX
    \o \c{-embedded i386} - builds the embedded version of Qt and sets the architecture to i386
    \o \c{-no-gfx-linuxfb},  \c{-no-mouse-linuxtp} and \c{-no-kbd-tty} are Linux specific and won't work on QNX
    \o \c{-no-qt3support} - required since the Qt3 support classes are not supported on QNX
    \o \c{-no-exceptions} - reduces the size of the library by disabling exception support
    \o \c{-qt-gfx-qnx} - enables the experimental \c{io-graphics} based display driver
    \o \c{-qt-mouse-qnx} - enables the experimental \c{devi-hig} based mouse driver
    \o \c{-qt-kbd-qnx} - enables the experimental \c{devi-hig} based keyboard driver
    \endlist

    \section1 General Notes

    \list
    \o To enable the experimental QNX display and input drivers, \c{io-display} needs to be
       up and running. The \c devi-hid based Qt input drivers require \c devi-hid to run
       in resource mode without Photon support. To enable a standard mouse and keyboard
       combination, run \c devi-hid as follows: \c{/usr/photon/bin/devi-hid -Pr kbd mouse}.
       Note that your current shell will not accept keyboard and mouse input anymore after
       running that command, so run it either from a script that launches a Qt application
       afterwards, or make sure to have remote login available to launch a Qt application.
       In addition, the \c QWS_DISPLAY, \c QWS_MOUSE_PROTO and \c QWS_KEYBOARD environment
       variables should all be set to \c{qnx} before running a Qt application.

    \o The 3rd party TIFF library currently doesn't build due to the missing \c inflateSync
       symbol from QNX's \c{libz.so.2}. Workarounds would be to manually replace QNX's libz
       with a newer version, or disable the TIFF plugin entierly by appending
       \c{QT_CONFIG += no-tiff} to \c{.qmake.cache} after configuring Qt.

    \o Some of the tools, examples and demos do not compile due to dependencies on QProcess
       or other classes that are not available on QNX.
    \endlist

    \section1 Platform Regressions

    Qt for QNX's behavior is mostly identical with \l{Qt for Embedded Linux}. However,
    some regressions were spotted in QDateTime computation around year 0 and year 1970,
    which have been tracked back to faulty time zone data on some QNX versions.
*/