Fun with custom Ubuntu ISO's

Apparently, when you are making an ISO the genisoimage command does not like it when you issue try to use a list of files and subdirectories as your argument, however, works fine when you present a single argument that is a directory name.

So let us say you are in the directory where you have configured your custom distro and you now want to pack it as a bootable ISO. It appears the safest syntax to use is something like this:

sudo genisoimage -no-emul-boot -boot-load-size 4 -boot-info-table  -b isolinux/isolinux.bin -c isolinux/boot.cat -V "my image" -o ../my_image.iso .

As a result, you get the image packed into my_image.iso one level above.

Additionally, here is a nice link to a manual on how to modify your distro step by step:

LiveCDCustomization

Playing with it right now. More to follow.

The mysterious evince

evince, otherwise known as "Document Viewer", is a pretty much standard feature of many a Linux distribution. So there I was, trying to use it on a mostly up-to-date Ubuntu 10.04 LTS 64-bit machine and I kept getting messages that looked like the following:

(evince:5691): EggSMClient-WARNING **: Failed to connect to the session manager: Authentication Rejected, reason : None of the authentication protocols specified are supported and host-based authentication failed

There were other messages as well, some stated that evince could not open the display(???) even though other X-applications, such as xterm, for instance, would run just fine from the same command line.

To make things even more bizarre that would happen for some users on the machine and not others. Attempts to play with Gnome settings - or even evince-specific settings - such as deleting ~/.gnome2 directory or specifically ~/.gnome2/evince subdirectory - appeared to be making no difference.

After some web searches I found a solution that seems to work. Hat tip to the participants of this discussion on the Ubuntu Forums. The following seemed to actually fix the problem for everybody:

sudo bash
cd /usr/bin
mv evince evince.bin
ln -s evince.bin evince

And don't ask me why!

ClipGrab

Oh, how fast things change!

Just a little while ago it looked like DamnVid was all the rage - but now YouTube has changed something and it is dead in the water. However, it looks like ClipGrab is a viable alternative... for now.

DamnVid

It came time to download some videos off YouTube to migrate them from one account to another... Dont' ask me why, that doesn't really matter. So, be that as it may - it is not as easy as it may seem. The FlashPlayer used to save them in your /tmp directory on Linux - but no more. The directory recommened at the link:

.mozilla/firefox/userprofile/cache

does not seem to contain anything resembling the video files one would expect either. However, then I followed a link specified at the above to get DamnVid and this seems to be working. The video ends up right under your ~/Videos directory hierarchy.

SANE: fixing an annoying network scan problem

On our network we've got a couple of Canon PIXMA network printer/scanner/FAX devices. Some versions of SANE apparently get confused trying to scan them with "network discovery" activated. The xsane application simply crashes.

After some searching on the web I have discovered what appears to be the fix. At least the fix has worked on a variety of Ubuntu 10.x machines, both 32-bit and 64-bit. I haven's saved the sources I used and can't locate them again so whoever was my inspiration on this one - please accept my apologies for failing to credit you.

So, be it as it may, here's the fix. Got to /etc/sane.d and edit the following file: epson2.conf . Comment out the following line:

net autodiscovery

You are done.

Final notice: after yet another round of updates on a 64-bit Ubuntu 10.10 machine I noticed that even this fix is not necessary it seems. But on slightly different installations this tip may still be of use.