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From: Rickard Jansson on 3 May 2010 04:17
"Ron Klein" <ron(a)xsights.com> wrote in message <hqv6c8$3pc$1(a)fred.mathworks.com>...
> "EBS " <ericDOTsampson(a)gmail.com> wrote in message <hqv1kv$3l0$1(a)fred.mathworks.com>...
> > "Ron Klein" <ron(a)xsights.com> wrote in message <hqu22a$4i4$1(a)fred.mathworks.com>...
> > >
> > > If you or any other person that reads this post have more ideas - please share them.
> > >
> > > Thanks again for the help so far.
> > >
> > > Ron
> >
> > Ron, did you see the post I made earlier?
> >
> > Check this thread (beware of line wrapping breaking the link), they talk about the undocumented 'mxSerialize' function, and another method using an undocumented SAVE stdio argument:
> > http://www.mathworks.com/matlabcentral/newsreader/view_thread/141797
>
> Yes, I entered the link you mention, but I couldn't find any code example.
> I'll investigate these undocumented functions, that's for sure.
> However, if there are some code examples out there (I tried google but nothing came up) - please post them here.
> And if, by any chance, somebody actually worked with these functions and could share his/her code - please do. Try pastebin ( http://pastebin.com/ ) for such sharing.
>
> Thanks all, your help is great and inspiring!
>
> Ron

Hi Ron,

I'm working with a similar scenario as you and also tried to use the undocumented mxSerialize/mxDeserialize routines in matlab.
I got them to work quite well in the 32-bit Linux version of matlab. But when I used them in the 64-bit version there was some trouble with the mxArray pointers returned from the mxDeserialize function. They seem to somehow become corrupted or truncated. This problem seem to occur when returning a mxArray* type from other functions as well. I might be doing something wrong here but the problem does not exist when running 32-bit matlab.

Because of the problems I went looking for another solution and found that functions for serializing and deserializing matlab objects had already been implemented in another project. The mym (http://sourceforge.net/projects/mym) uses this to store matlab objects as binary blobs in a mysql-database.
At first I had the same problems as described above with these function because they also returned mxArray pointers, but with the source code available I could try some alternative approaches.
Instead I rewrote them to pass the mxArray* pointer where I wanted the results as a parameter to the function.
An example:
void deserializeStruct(const char* rpSerial, const unsigned long rlength, mxArray** rpOut);

This seem to work, but I still haven't figured out why it works this way but not when passing the pointer as a return value.

/ Rickard
From: Ron Klein on 3 May 2010 05:00
"Rickard Jansson" <rickard.u.jansson(a)gmail.com> wrote in message <hrm0q3$k1o$1(a)fred.mathworks.com>...
> "Ron Klein" <ron(a)xsights.com> wrote in message <hqv6c8$3pc$1(a)fred.mathworks.com>...
> > "EBS " <ericDOTsampson(a)gmail.com> wrote in message <hqv1kv$3l0$1(a)fred.mathworks.com>...
> > > "Ron Klein" <ron(a)xsights.com> wrote in message <hqu22a$4i4$1(a)fred.mathworks.com>...
> > > >
> > > > If you or any other person that reads this post have more ideas - please share them.
> > > >
> > > > Thanks again for the help so far.
> > > >
> > > > Ron
> > >
> > > Ron, did you see the post I made earlier?
> > >
> > > Check this thread (beware of line wrapping breaking the link), they talk about the undocumented 'mxSerialize' function, and another method using an undocumented SAVE stdio argument:
> > > http://www.mathworks.com/matlabcentral/newsreader/view_thread/141797
> >
> > Yes, I entered the link you mention, but I couldn't find any code example.
> > I'll investigate these undocumented functions, that's for sure.
> > However, if there are some code examples out there (I tried google but nothing came up) - please post them here.
> > And if, by any chance, somebody actually worked with these functions and could share his/her code - please do. Try pastebin ( http://pastebin.com/ ) for such sharing.
> >
> > Thanks all, your help is great and inspiring!
> >
> > Ron
>
> Hi Ron,
>
> I'm working with a similar scenario as you and also tried to use the undocumented mxSerialize/mxDeserialize routines in matlab.
> I got them to work quite well in the 32-bit Linux version of matlab. But when I used them in the 64-bit version there was some trouble with the mxArray pointers returned from the mxDeserialize function. They seem to somehow become corrupted or truncated. This problem seem to occur when returning a mxArray* type from other functions as well. I might be doing something wrong here but the problem does not exist when running 32-bit matlab.
>
> Because of the problems I went looking for another solution and found that functions for serializing and deserializing matlab objects had already been implemented in another project. The mym (http://sourceforge.net/projects/mym) uses this to store matlab objects as binary blobs in a mysql-database.
> At first I had the same problems as described above with these function because they also returned mxArray pointers, but with the source code available I could try some alternative approaches.
> Instead I rewrote them to pass the mxArray* pointer where I wanted the results as a parameter to the function.
> An example:
> void deserializeStruct(const char* rpSerial, const unsigned long rlength, mxArray** rpOut);
>
> This seem to work, but I still haven't figured out why it works this way but not when passing the pointer as a return value.
>
> / Rickard

Hi Rickard,

This mym project and link seem to be very helpful. Thumbs up!!
Can you share your altered code snippets?

Thanks,

Ron
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