On Wednesday, October 12, 2011 04:33:53 PM Alan Stern did opine: > On Wed, 12 Oct 2011, gene heskett wrote: > > Greetings; > > > > to be able to redirect an assembly listing created by an assembler, to > > /dev /usblp3 > > > > This command line fails: > > [gene@coyote Download]$ mamou -l dcheckmine.asm 2>&1 >/dev/usblp3 > > bash: /dev/usblp3: Permission denied > > Instead of redirecting the output to /dev/usblp3, pipe it to lpr with > the appropriate -P argument. See "man lpr". > > > Running as the un-priviledged user gene. > > > > And yet this printer is usable through cupsd by me after unplugging > > and replugging the parent usb hub AND restarting cups. It was > > present on the system and powered up at the last reboot, but not > > discovered. > > > > Much of this could be prevented if this printer, at least 3 hubs away > > from a motherboard usb port because of its physical location on > > another desk in the basement, was discovered at bootup time. > > However, in order for udevs discovery to work, I am finding that > > after a reboot I must disconnect the motherboard port to hub cable, > > wait a few seconds, and then reconnect it, at which time the > > discovery works normally. > > > > So, 2 questions really, why can't I (a normal user) use it, and why is > > it not properly discovered at bootup? > > I think normal users aren't supposed to be able to access printers > directly. They're supposed to use programs in the cups package (like > lpr) for printing. This may vary according to your distribution. This does not always work if the usb tree has been re-discovered due to a disconnect after boot even if it finds it when reconnected. What I need is for lpr to be able to use the BROTHE2140 printer at any time it is plugged in, even if the parent hub has been disconnected for 5 seconds every hour on the hour since the last reboot 3 weeks ago. > Discovery at bootup _ought_ to work. To find out why not, the best > approach is to build a kernel with CONFIG_USB_DEBUG enabled and post > the resulting boot-up dmesg log. For comparison, also post a log > showing what happens when the hub cable is reconnected after boot-up > (using the same kernel). Build in progress, using the .config that built this 2.6.38.8-bfs-pae kernel with CONFIG_USB_DEBUG now set. But using my "makeit" script which keeps a backup copy of the kernel it is replacing. > Alan Stern Thanks Alan, I should be back with a couple dmesgs in a few hours. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) An artist should be fit for the best society and keep out of it. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
