setopt noclobber in /proc-filesystem

setopt noclobber in /proc-filesystem

[Michael Prokop]

Hello,

% setopt noclobber
% echo foo > /proc/sys/kernel/hotplug
zsh: file exists: /proc/sys/kernel/hotplug

Is there any chance to use option 'noclobber' but allow writing to
/proc-filesystem anyway? I do know that there exists 'setopt
clobber' ;-) and "echo ... >| /proc/..." as well but other users
might not know this.

I'd like to ship zsh on my live-cd-system with 'setopt noclobber'
enabled but would like to avoid that users think the behaviour in
/proc-fs is a bug.  Any ideas?

regards,
-mika-
-- 
 ,'"`.         http://www.michael-prokop.at/
(  grml.org -» Linux for texttool-users and sysadmins
 `._,'         http://www.grml.org/

Re: setopt noclobber in /proc-filesystem

[Dan Nelson]

In the last episode (Aug 15), Michael Prokop said:
> % setopt noclobber
> % echo foo > /proc/sys/kernel/hotplug
> zsh: file exists: /proc/sys/kernel/hotplug
> 
> Is there any chance to use option 'noclobber' but allow writing to
> /proc-filesystem anyway? I do know that there exists 'setopt
> clobber' ;-) and "echo ... >| /proc/..." as well but other users
> might not know this.
> 
> I'd like to ship zsh on my live-cd-system with 'setopt noclobber'
> enabled but would like to avoid that users think the behaviour in
> /proc-fs is a bug.  Any ideas?

sysctl -w kernel.hotplug=foo

-- 
	Dan Nelson
	dnelson@allantgroup.com

Re: setopt noclobber in /proc-filesystem

[Nikolai Weibull]

Dan Nelson wrote:

> In the last episode (Aug 15), Michael Prokop said:

> > % setopt noclobber
> > % echo foo > /proc/sys/kernel/hotplug
> > zsh: file exists: /proc/sys/kernel/hotplug

> sysctl -w kernel.hotplug=foo

Hahaha, very good solution,
        nikolai

-- 
Nikolai Weibull: now available free of charge at http://bitwi.se/!
Born in Chicago, IL USA; currently residing in Gothenburg, Sweden.
main(){printf(&linux["\021%six\012\0"],(linux)["have"]+"fun"-97);}

Re: setopt noclobber in /proc-filesystem

[Michael Prokop]

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* Dan Nelson <dnelson@allantgroup.com> [20050815 17:15]:
> In the last episode (Aug 15), Michael Prokop said:

> > % setopt noclobber
> > % echo foo > /proc/sys/kernel/hotplug
> > zsh: file exists: /proc/sys/kernel/hotplug

> > Is there any chance to use option 'noclobber' but allow writing to
> > /proc-filesystem anyway? I do know that there exists 'setopt
> > clobber' ;-) and "echo ... >| /proc/..." as well but other users
> > might not know this.

> > I'd like to ship zsh on my live-cd-system with 'setopt noclobber'
> > enabled but would like to avoid that users think the behaviour in
> > /proc-fs is a bug.  Any ideas?

> sysctl -w kernel.hotplug=foo

Hehe, I'd like to find a solution for the zsh-echo->/proc. ;)

*I* do know that I can use sysctl and 'echo >|...' but other users
do *not*. Therefore I need a solution where something like
echo 3 > /proc/acpi/sleep
works out-of-the-box.

regards,
-mika-
-- 
 ,'"`.         http://www.michael-prokop.at/
(  grml.org -» Linux for texttool-users and sysadmins
 `._,'         http://www.grml.org/

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Re: setopt noclobber in /proc-filesystem

[Oliver Kiddle]

Michael Prokop wrote:
> 
> *I* do know that I can use sysctl and 'echo >|...' but other users
> do *not*. Therefore I need a solution where something like
> echo 3 > /proc/acpi/sleep
> works out-of-the-box.

The only way to do that would be to modify the C code to check the
filesystem type of the file being written to.

Alternatively, you might want to rethink why you want to impose the
noclobber option on your users. You may like the option but many people,
including myself, find it to be a nuisance.

Oliver


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Re: setopt noclobber in /proc-filesystem

[Michael Prokop]

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* Oliver Kiddle <okiddle@yahoo.co.uk> [20050817 12:42]:
> Michael Prokop wrote:

> > *I* do know that I can use sysctl and 'echo >|...' but other users
> > do *not*. Therefore I need a solution where something like
> > echo 3 > /proc/acpi/sleep
> > works out-of-the-box.

> The only way to do that would be to modify the C code to check the
> filesystem type of the file being written to.

Ok, thanks for clarification!

> Alternatively, you might want to rethink why you want to impose the
> noclobber option on your users. You may like the option but many people,
> including myself, find it to be a nuisance.

Yes, that's what I'll do. Thanks!

regards,
-mika-
-- 
 ,'"`.         http://www.michael-prokop.at/
(  grml.org -» Linux for texttool-users and sysadmins
 `._,'         http://www.grml.org/

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Re: setopt noclobber in /proc-filesystem

[Wayne Davison]

On Mon, Aug 15, 2005 at 01:14:55PM +0200, Michael Prokop wrote:
> Is there any chance to use option 'noclobber' but allow writing to
> /proc-filesystem anyway?

I can imagine using a preexec() function to examine the command-line
and setting noclobber on or off based on whether it looks like the
command is trying to redirect to a file in /proc.

..wayne..