Segmentation error at the end problem (148 line program listing)

[Gide Nwawudu]

On Wed, 28 Jan 2009 13:37:40 -0800, Charles Hixson
<charleshixsn at earthlink.net> wrote:

>Gide Nwawudu wrote:
>> On Tue, 27 Jan 2009 22:48:33 -0800, Charles Hixson
>> <charleshixsn at earthlink.net> wrote:
>> 
>>> Main routine:
>>>
>>> void	main()
>>> {
>>>    try
>>>    {  BlockFile	bf;
>>>       bf  =  new BlockFile ("test.bf", 4096);
>>>       writefln ("before close");
>>>       bf.close;
>>>       bf  =  null;
>>>       writefln ("after close");
>>>       BlockFile	cf  =  new  BlockFile ("test.bf", 4096);
>>>       writefln ("after second open");
>>>    }
>>>    catch (Exception e)
>>>    {  writefln ("Caught Exception ", e);  }
>>> }
>>>
>>> Results in:
>>> Exiting BlockFile::this
>>> before close
>>> after close
>>> Exiting BlockFile::this
>>> after second open
>>> Segmentation fault
>>>
>>> I could post all the code.  It's only 146 lines.  But perhaps this is 
>>> enough?
>> 
>> I'm thinking it might be an issue with close and the dtor being called
>> on the same object. If you add std.gc.fullCollect() after the bf =
>> null. Does that make the code seg fault before 'after close' is
>> written? 
>> 
>> Gide
>I had to wriggle the code around a bit. (It's D2 not D1.)  However it 
>didn't make any difference to do:
>void	main()
>{
>	try
>	{	BlockFile	bf;
>		bf	=	new	BlockFile ("test.bf", 4096);
>		writefln ("before close");
>		bf.close;
>		bf	=	null;
>		GC.collect;
>		writefln ("after close");
>		BlockFile	cf	=	new	BlockFile ("test.bf", 4096);
>		writefln ("after second open");
>	}
>	catch (Exception e)
>	{	writefln ("Caught Exception ", e);	}
>}
>
>   -------------------
>And the docs say that GC.collect does a full collect;
>
>P.S.:  Attached is the full listing

Calling close and dtor on BufferedFile is the problem. Rewiting
BlockFile.close as follows fixes the problem, but I think your code
should work.

void close() { delete bf; bf = null; }

Gide