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From: ravi <ravi.nanjundappa@ap.sony.com>
To: Robert Watson <rwatson@freebsd.org>
In-Reply-To: <Pine.NEB.3.96L.1040720223851.12507E-100000@fledge.watson.org>
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Date: Tue, 03 Aug 2004 15:23:14 +0530
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cc: Brian Fundakowski Feldman <green@freebsd.org>
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cc: Dan Nelson <dnelson@allantgroup.com>
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cc: Aniruddha Bohra <bohra@cs.rutgers.edu>
cc: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
Subject: Regarding writing to /proc entries
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Hi,
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

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