On 09/13/2011 05:07 PM, John Andersen wrote:
David's Flash cards thru a reader vs Tejas's USB sticks are two different problems.
USB in all recent versions of OpenSuse mount in quick removal mode (aka synchronous mode) where the application receives indication that the write is complete only when it IS IN FACT complete, there is no caching, and files are closed and fat is written after each file. It makes for terrible performance, but its safer.
With a reader, depending on how it is connected, it may not appear as USB (even if it is in fact USB), in which case all bets are off, and you have to use safely remove option.
There is still a problem with Safely remove in Linux for USB. It is not the same as EJECT.
There seems no way to do an eject in KDE yet. The two are quite different, EJECT is not normally done even if you click the USB applet and select what appears to be the eject icon. This is not a problem for USB sticks that are accessed in synchronous mode.
But it can be a big problem for things that pretend to be USB devices, such as many android phones, Nook Ereaders, etc.
For these to recognize that you are truly finished, you have to EJECT. And with KDE, You have to do this from the command line, or wait a long time for your device to quiesce.
I found this out after trashing my Nook storage some time back.
I follow up a bit with Patrick on this. The card reader I have is: (from lspci) Mass storage controller: Texas Instruments 5-in-1 Multimedia Card Reader (SD/MMC/MS/MS PRO/xD) The flash drives were normal SD drives used in Kodak cameras. The drives were mounted under /media/disk. The copy from the card reader was done with 'cp -ur'. The flash drives were unmounted after the copy operation and long before the SD cards were removed from the card reader. All operations were done in the same konsole window, so the possibility of an unmount or removal of the SD drive before all operations were completed was an impossibility. (umount would fail if any files were left open or copy operations left in progress) When using the SD flash drive through the card reader, jpeg image corruption was a big issue. As mentioned, parts of the jpeg header would be preserved, but other parts were fried -- resulting in corrupt photos. Downloading the same files when the 'camera' was connected through the USB port worked fine. It was only when the SD drive connected through the card reader that corruption occurred. I never got to the bottom of this, but for George's purposes, image corruption of photos is serious enough (especially when you delete them from the flash drive before viewing them), that it was worth noting. Now, the odd part of my copy/corruption problem is that -- the full image size was copied from the SD drive to the hard drive -- but for some reason the header information was screwed. That is also on the 'unexplained' list. So I think John framed the issue correctly: copy from USB - OK copy from card reader - All bets are off Hopefully I'll have more time to dig into this issue and solve it. It was a heck of a lot quicker to pop the flash drive from the camera into the reader and launch a script that would automatically copy to the local hard drive and rsync to the local server, than it is to download the same photos through digikam and then do the same post processing on the file... -- David C. Rankin, J.D.,P.E. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org