diff options
Diffstat (limited to 'src/corelib/io/qwinoverlappedionotifier.cpp')
| -rw-r--r-- | src/corelib/io/qwinoverlappedionotifier.cpp | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/corelib/io/qwinoverlappedionotifier.cpp b/src/corelib/io/qwinoverlappedionotifier.cpp index 3f599e464f..d7745ae1b6 100644 --- a/src/corelib/io/qwinoverlappedionotifier.cpp +++ b/src/corelib/io/qwinoverlappedionotifier.cpp @@ -81,6 +81,22 @@ QT_BEGIN_NAMESPACE or WriteFile() is ignored and can be used for other purposes. \warning This class is only available on Windows. + + Due to peculiarities of the Windows I/O completion port API, users of + QWinOverlappedIoNotifier must pay attention to the following restrictions: + \list + \li File handles with a QWinOverlappedIoNotifer are assigned to an I/O + completion port until the handle is closed. It is impossible to + disassociate the file handle from the I/O completion port. + \li There can be only one QWinOverlappedIoNotifer per file handle. Creating + another QWinOverlappedIoNotifier for that file, even with a duplicated + handle, will fail. + \li Certain Windows API functions are unavailable for file handles that are + assigned to an I/O completion port. This includes the functions + \c{ReadFileEx} and \c{WriteFileEx}. + \endlist + See also the remarks in the MSDN documentation for the + \c{CreateIoCompletionPort} function. */ struct IOResult |