Should KFilterDev::readData() and writeData() be protected access?

Thiago Macieira thiago at
Thu May 31 12:04:15 BST 2007

Richard Dale said:
> In QIODevice the readData() and writeData() pure virtual methods have
> protected access:
> protected:
> #ifdef QT_NO_QOBJECT
>     QIODevice(QIODevicePrivate &dd);
> #else
>     QIODevice(QIODevicePrivate &dd, QObject *parent = 0);
> #endif
>     virtual qint64 readData(char *data, qint64 maxlen) = 0;
>     virtual qint64 readLineData(char *data, qint64 maxlen);
>     virtual qint64 writeData(const char *data, qint64 len) = 0;
> KFilterDev subclasses QIODevice, and implements these methods with access
> public, but shouldn't they be protected?

Yes. My guess is someone ported the old readBlock, readLine and writeBlock
public virtual methods from Qt3's QIODevice, renamed them and forgot to
make them protected.

The *Data versions must not be called directly in a QIODevice because they
skip the QIODevice's buffering system and may lead to inconsistent

  Thiago Macieira  -  thiago (AT) - thiago (AT)
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