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devctl messages, return data with pointers

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devctl messages, return data with pointers

Postby juro » Wed Sep 19, 2007 8:51 am

Hi all,

I have test application and resouce manager and I use devctlv to send some data with pointers from application to resouce manager and in this way work ok.But I also need to return some pointer data from resouce manager to the test application.It is possible to do and how can I solve this problem?

Thanks

Juraj
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RE: devctl messages, return data with pointers

Postby maschoen » Wed Sep 19, 2007 3:21 pm

I'm not sure what use pointers would be between separate processes, unless you are using shared memory, but in any case, with message passing data goes both ways. Likewise devctl can receive and send back data. Are you having trouble getting devctl to work right? Make sure you are using the right macros to define your commands.
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RE: devctl messages, return data with pointers

Postby juro » Wed Sep 19, 2007 4:40 pm

hi,
I use devctlv not devctl because of data with pointers.devctlv is proposed to handle structure data with some pointers inside.In resouce manager I can read this data which was send from test application in call back function.But I don't know how to send return data back to the test application.

Thanks

Juraj
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RE: devctl messages, return data with pointers

Postby maschoen » Wed Sep 19, 2007 5:45 pm

That's interesting. I can't find devctlv in the Help on 6.3.3?
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Re: devctl messages, return data with pointers

Postby David Gibbs » Tue Oct 09, 2007 9:00 pm

juro <juraj.frank@naex-dot-sk.no-spam.invalid> wrote:
hi,
I use devctlv not devctl because of data with pointers.devctlv is
proposed to handle structure data with some pointers inside.In
resouce manager I can read this data which was send from test
application in call back function.But I don't know how to send return
data back to the test application.

Just MsgReply() with the io_devctl_reply header followed by the data
that you want to return. (Or, MsgReplyv().)

-David
--
David Gibbs
QNX Training Services
dagibbs@qnx.com
David Gibbs
 


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