[PD] Reading and writing binary files

[Jonathan Wilkes]

--- On Mon, 2/28/11, Mathieu Bouchard <matju at artengine.ca> wrote:

> From: Mathieu Bouchard <matju at artengine.ca>
> Subject: Re: [PD] Reading and writing binary files
> To: "David" <dfkettle at gmail.com>
> Cc: "pd-list" <pd-list at iem.at>, "Martin Peach" <martin.peach at sympatico.ca>
> Date: Monday, February 28, 2011, 3:31 AM
> On Sun, 27 Feb 2011, David wrote:
> 
> > I have another question, though. How do the files get
> closed? When you exit PureData? Does that mean that every
> time you open a file, another system file handle is used and
> not released until you exit PureData? Or is there some way
> to explicitly close the file and release the file handle,
> buffers, etc.?
> 
> This depends on every object class.
> 
> In the case of [binfile] [textfile] [qlist] [soundfiler],
> the 'read' method copies the whole file to RAM and closes
> immediately the filehandle.
> 
> In the case of [#io.grid] ([#in grid]) and video readers,
> there is 'open'
> and there is 'close'.
> 
> In [readsf~] it's slightly different, as 'stop' or '0'
> implies closing, but it's not documented as such in Miller's
> manual. The structure of 'open' followed by 'start'/'1' and
> then 'stop'/'0' would suggest that there is a separate
> 'close', and thus that after a stop you'd be able to resume
> without reopening, but this is not the case. (!!!)
> 
> GridFlow's 'load' in image readers is just a shortcut for
> an 'open' 'bang' 'close' sequence.
> 
> I think I remember that someone has found a filehandle leak
> bug somewhere in Pd, but I don't recall what that was.
> Anyone remembers ?

Well, I know if I read a ca. 15mb file with [textfile], it takes about 
10 seconds to load, then if I try to iterate through the file with 
[until] Pd will freeze.

-Jonathan

> 
> 
> _______________________________________________________________________
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