[lug] C++ libraries in Linux

[Keith Brown]

Your are right in unfreezing it.

"Scott A. Herod" wrote:

> I knew that I shouldn't post any source code and show off how badly
> I write. :-(
>
> Looking at the gcc3 headers, it doesn't appear that they've yet
> incorporated
> stringstream.
>
> The destructor for the strstream class is defined as so:
> strstream::~strstream() {}
>
> In the strstreambuf destructor it appears that the char* buffer is only
> freed if the stream is not frozen:
>
> strstreambuf::~strstreambuf()
> {
>   if (_M_dynamic && !_M_frozen)
>     _M_free(eback());  // eback() apparently returns a pointer to the
>                        // front of the buffer
> }
>
> So, I think now that my code should be:
>
> > #include <strstream>
> > string paraNode::toString()
> > {
> >     string rtnval;
> >     strstream buf;
> >
> >     buf << "Paragraph: "
> >         << ATTR_ALIGN << " = " << _align << ", "
> >         << ATTR_WRAP_MODE << " = " << _mode
> >         << ends;
> >     rtnval = buf.str();
>
>       buf.freeze( false );
>
> >     return rtnval;
> > }
>
> Keeping in the original thread; no comments on this subject at
> dinkumware.
>
> http://www.dinkumware.com/htm_cpl/strstrea.html
>
> Scott
>
> Keith Brown wrote:
> >
> > I hate to reply to my own mail, but my example is not correct.  The buf should be
> > unfrozen with buf.freeze(false), at least according to Josuttis.  Additionally,
> > strstream has been depreciated and he suggest you use stringstream.
> >
> > Keith
> >
> > Keith Brown wrote:
> >
> > > Hi,
> > >
> > > I believe you have memory leak in your example.  Once you do buf.str(), the
> > > program owns the *char that is returned, unless it tells strstream otherwise,
> > > which I forget how to do.  I believe you need to do it like:
> > >
> > > char * s = buf.str();
> > > rtnval = s;
> > > delete [] s;
> > > return rtnval;
> > >
> > > Keith
> > >
> > > "Scott A. Herod" wrote:
> > >
> > > > Hi,
> > > >   I use something like the following:
> > > >
> > > > #include <strstream>
> > > > string paraNode::toString()
> > > > {
> > > >     string rtnval;
> > > >     strstream buf;
> > > >
> > > >     buf << "Paragraph: "
> > > >         << ATTR_ALIGN << " = " << _align << ", "
> > > >         << ATTR_WRAP_MODE << " = " << _mode
> > > >         << ends;
> > > >
> > > >     rtnval = buf.str();
> > > >     return rtnval;
> > > > }
> > > >
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--
Keith Brown
12640 Xavier St
Broomfield, CO 80020
303.438.8169