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From: Robert Watson <rwatson@freebsd.org>
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To: ravi <ravi.nanjundappa@ap.sony.com>
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cc: Aniruddha Bohra <bohra@cs.rutgers.edu>
cc: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
Subject: Re: Regarding writing to /proc entries
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On Tue, 3 Aug 2004, ravi wrote:

> The README file in /sys/fs/procfs directory says that we can send the
> control messages to note or ctl files for any process . But when we
> execute the command 
> 
> 	echo hup > /proc/curproc/note
> 
> 		OR
> 	echo attach > /proc/2/ctl

It may be because you're writing the word and a line feed, and it could be
our note file doesn't know what to do with the line feed.  Try "echo -n" 
instead? 

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Principal Research Scientist, McAfee Research


> 
> the following error message comes on the terminal .
> 
> $ echo hup > /proc/curproc/note
> /proc/curproc/note: Operation not supported
> 
> and 
> 
> $ echo attach > /proc/2/ctl
> /proc/2/ctl: Operation not supported
> 
> 
> 
> What is the reason for this ?
> 
> Is it not possible to write the control words or control messages to the
> process entries under /proc ?
> 
> Please reply to this mail .
> 
> Regards,
> N Ravi
> 
> 
> 
> 
>