site  contact  subhomenews

Woof uploaded December 23, 2009 (again)

December 23, 2009 — BarryK
As explained in recent blog posts, there is a problem in some cases with hotplugging of memory cards, with the deskop drive icons not appearing (or disappearing).

See recent posts:
http://bkhome.org/archive/blog2/200912/pcmciammcsd-support-at-bootup-hotplug-drives.html
http://bkhome.org/archive/blog2/200912/sd-card-support-at-bootup.html

I had a solution, that used 'dd' to read from removable USB drives every two seconds, however I wasn't happy with it. I don't like the idea of a plugged-in card being read every two seconds.

So, I have worked on /sbin/pup_event_frontend_d and now have it so 'dd' only runs when a card is not plugged in. It works nicely, except that removal of a card is now not properly detected, meaning that an icon may remain on the desktop after a card is unplugged -- however I modified /usr/local/bin/drive_all to detect an invalid icon if it is clicked on and it is then removed.

This is a workable compromise, with low overheads, and most inportantly I think doesn't keep reading from a card every 2 seconds to see if it is still there.

Actually, the problem is at the kernel and kernel driver level, and it might go away as the kernel keeps improving. For example, external drive sde, and I plug in a card, /sys/block/sde/sde1 directory appears -- but when I unplug the card that directory remains indefinitely -- until an attempt is made to read from that drive (as with 'dd').

Anyway, I have uploaded Woof with this latest solution.

Tags: woof