On Wed, 2005-10-26 at 12:22 +0100, Dave Chapman wrote:

On Wednesday 26 October 2005 12:01, Dave Howorth wrote:

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... So what I do is su to root and eject it. I've been thinking about writing a suid shell script to do that, unless somebody else comes with a better suggestion.

I dont know what version of SUSE you have but 10 has a service menu (right click) "safely remove"

I use 9.3 with gnome. Enlightenment has 'unmount device' (IIRC) but it doesn't work - it gives the 'you aren't root' message. If yours works, could you post the actual command that is run by 'safely remove'? Or tell me which configuration file it's in, or at least which software component is providing that menu on your system. Thanks, Dave

Dave Chapman wrote:

On Wednesday 26 October 2005 13:20, Dave Howorth wrote:

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On Wed, 2005-10-26 at 12:22 +0100, Dave Chapman wrote:

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On Wednesday 26 October 2005 12:01, Dave Howorth wrote:

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... So what I do is su to root and eject it. I've been thinking about writing a suid shell script to do that, unless somebody else comes with a better suggestion.

I dont know what version of SUSE you have but 10 has a service menu (right click) "safely remove"

You don't need to do all of this, just make sure any disc activity has finished and unplug the device. As Dorothy once said to Toto:

"I don't think we are using Windows anymore...." Ok, she didn't say that, it just sounded cool. James W

On 28/10/05, Dave Howorth wrote:

On Thu, 2005-10-27 at 17:41 -0400, James Wright wrote:

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On Wednesday 26 October 2005 12:01, Dave Howorth wrote:

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... So what I do is su to root and eject it. I've been thinking about writing a suid shell script to do that, unless somebody else comes with a better suggestion.

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You don't need to do all of this, just make sure any disc activity has finished and unplug the device.

I think you missed something I wrote earlier:

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My disk is a camera (well, the disk is an SD card in a camera) and this doesn't work because I want to turn the camera off before unplugging it. And it won't turn off until it's unmounted ...

Cheers, Dave

Perhaps I'm missing something here but what's wrong with simply unplugging the camera? Or, get hold of one the now very cheap USB card readers. That's why I 'have' to use as my camera is not supported under any distro. It does have the added bonus of not wasting the cameras battery. -- ============================================== I am only human, please forgive me if I make a mistake it is not deliberate. ============================================== Take care. Kevan Farmer 34 Hill Street Cheslyn Hay Staffordshire WS6 7HR

On 28/10/05, Dave Howorth wrote:

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Perhaps I'm missing something here but what's wrong with simply unplugging the camera?

Because the manufacturer's instructions say to turn off the camera before plugging/unplugging and I don't want to void my warranty.

Ah, I understand. Very good point.

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Or, get hold of one the now very cheap USB card readers. That's why I 'have' to use as my camera is not supported under any distro. It does have the added bonus of not wasting the cameras battery.

Because my camera is supported :) I checked before I bought. Why should I have to fiddle around taking the card out?

Cheers, Dave

Good point number two :-) Never mind, they were just suggestions. -- ============================================== I am only human, please forgive me if I make a mistake it is not deliberate. ============================================== Take care. Kevan Farmer 34 Hill Street Cheslyn Hay Staffordshire WS6 7HR

On 28/10/05, Randall R Schulz wrote:

Dave,

On Friday 28 October 2005 03:45, Dave Howorth wrote:

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On Fri, 2005-10-28 at 11:37 +0100, Kevanf1 wrote:

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Perhaps I'm missing something here but what's wrong with simply unplugging the camera?

Because the manufacturer's instructions say to turn off the camera before plugging/unplugging and I don't want to void my warranty.

Sorry, but USB is _by definition_ hot pluggable. This is probably a nonsense requirement promulgated by an ignorant party or a CYA attitude within the manufacturer's organization. It may also have to do with a misunderstanding of the limits of using removable USB storage media under Windows.

Don't stay backed into a corner. Use the SuSE default synchronous writing for USB mass (or flash) storage devices and just disconnect when the commands that write to the device complete. If you're reading it only, disconnect whenever you like.

Similarly, there's no reason you can't turn it off first if that makes you feel better. Again, use synchronous writing. When the device goes away, Linux will clean up its internal structures.

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Cheers, Dave

Randall Schulz

Well, again, I may be missing something here, but.. surely the only reason not to simply unplug a USB device when you want to is if any data was being cached instead of written direct to the disk (or storage device). Does this happen in this case? I know that you couldn't simply unplug old style serial or parallel port drives etc because of the risk of burning the port out, this shouldn't happen with USB. Should it? -- ============================================== I am only human, please forgive me if I make a mistake it is not deliberate. ============================================== Take care. Kevan Farmer 34 Hill Street Cheslyn Hay Staffordshire WS6 7HR

On Friday 28 October 2005 17:01, Kevanf1 wrote:

I know that you couldn't simply unplug old style serial or parallel port drives etc because of the risk of burning the port out, this shouldn't happen with USB.  Should it?

No, the automounting is in sync mode so you should be able to unplug any time there is no activity. I have never heard of a usb port "burning out." Bryan ******************************************************** Powered by SuSE Linux 9.2 Professional KDE 3.3.0 KMail 1.7.1 This is a Microsoft-free computer Bryan S. Tyson bryantyson@earthlink.net ********************************************************

Kevan, On Saturday 29 October 2005 02:08, Kevanf1 wrote:

On 29/10/05, Bryan Tyson wrote:

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On Friday 28 October 2005 17:01, Kevanf1 wrote:

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I know that you couldn't simply unplug old style serial or parallel port drives etc because of the risk of burning the port out, this shouldn't happen with USB. Should it?

No, the automounting is in sync mode so you should be able to unplug any time there is no activity. I have never heard of a usb port "burning out."

Bryan

Ok, I'm with you guys so far :-) Now, my next question is how do you know when data has finished its transfer to the USB device? I know that a lot of USB devices have a light that wither blinks on and off or stays on during data transfer. But there must be a another way of registering the transfer - it usually opens a window if you are in GUI mode but this is not the case in command prompt mode. What I'm getting at is the same as with a car. You should never rely on the oil warning light to come on and tell you that you are low on oil because the light/bulb may have blown or be otherwise defective. The same goes for this tell tale light on the USB device. Or am I now worrying for no reason?

For god's sake, drop the automotive analogies, OK? Once again, ... There are two parts to synchronous file system writing. One is that the kernel does not hold on to dirty buffers--it always flushes them to the device immediately upon receipt of new data from the user-level application. The other is that it does not return control from the write system call that sent data to the device until the write is complete. If you're using simple GUI commands that perform some operation and return (as opposed to interactive commands which _might_ be multi-threaded, though many are not), then by the time you see the prompt after issuing the command that sends data to the USB-attached device, all the I/O is complete and the device may be disconnected. And LEDs have a very, very, very long lifetime. You'll have long abandoned your USB device as obsolete for one reason or another (or because it has failed, stopped on or dropped in the toilet) before the indicator lights stop working.

.. Kevan Farmer

Randall Schulz

On Friday 28 October 2005 05:15, Dave Howorth wrote:

I think you missed something I wrote earlier:

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My disk is a camera (well, the disk is an SD card in a camera) and this doesn't work because I want to turn the camera off before unplugging it. And it won't turn off until it's unmounted ...

Two possible answers: 1. Unplug it first, then turn it off. 2. For $15-25 get a USB SD card reader and plug it into your computer without the camera. Bryan ******************************************************** Powered by SuSE Linux 9.2 Professional KDE 3.3.0 KMail 1.7.1 This is a Microsoft-free computer Bryan S. Tyson bryantyson@earthlink.net ********************************************************

Doesn't that sort of defeat the object of being able to hotplug USB devices? Plus, I could use sudo to get round the problem, but think there must be a better way??? Cheers, Jon. Dave Howorth wrote:

On Wed, 2005-10-26 at 11:11 +0100, Jonathan Brooks wrote:

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.... The USB harddisk is mouted automatically by HAL. This bypasses /etc/fstab, and thus (from a non-root user's perspective) is not actually mounted.

When they issue a umount command, they get the error message "/media/foo is not listed in the mnttab, and anyway you're not root, so piss off"

So what is the solution? Sync then unplug the disk?

My disk is a camera (well, the disk is an SD card in a camera) and this doesn't work because I want to turn the camera off before unplugging it. And it won't turn off until it's unmounted ...

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Come on, I'm sure loads of people must use these disks - what's the recommended way to disconnect them??????

... So what I do is su to root and eject it. I've been thinking about writing a suid shell script to do that, unless somebody else comes with a better suggestion.

Cheers, Dave