Write Access

Write Access

Article from Issue 97/2008


DVD and fwknop

I'm considering getting a subscription, but I'm a little confused. The flyer advertising the US$ 9.99 "trial" mentions a "DVD Subscription." Is there an alternate subscription that doesn't come with the DVDs?

Also, is it possible to purchase individual magazines through an online ordering method?

Finally, to be somewhat critical… I think I've read the fwknop article three or four times now in several different issues. I have also noticed that the articles in the special editions (e.g., the one for openSUSE 11) are repeated in other issues. Is this a normal practice?

Thanks for the great magazine.

Elijah Snyder


Yes, it is possible to subscribe without the DVD. See the details at our website. You can also order back issues online:


We do occasionally reprint some articles in our special editions, although we always try to give each special enough new material to make it a useful and original product. One of the reasons for our special editions is to share some of the best articles from the regular magazine with a new audience.

As for the fwknop question, that was kind of an unusual circumstance that doesn't happen often, but it might come up occasionally. Our regular columnists operate fairly independently. In this case, Charly wrote a two-part series on port knocking tools (in the September and October issues) without knowing that we had previously run a feature article on port knocking (in the June issue).

In our opinion, Charly's brief, one-page format is distinct enough that the two Charly articles could co-exist with the previous article. We sometimes print different takes on the same topic, just to show the subject from different viewpoints, so it seemed OK to us at the time.

We'll stay away from fwknop for a while.

Photo Perl

I had been dithering around about going all-Linux for some time, and I had whittled the hurdles down to a handful, one of which was printing family photos on my HP Photosmart 8250. The HP software in Windows automatically crops to a 4x6 and prints through the photo tray. Linux has no acceptable driver for Gutenprint, so I had to format, then go to the CUPS printer page to reset for photo tray printing, then print, then reset to the normal tray.

Then I blundered into the CUPS command line, which lets me activate the photo tray for a print job.

I encountered your piece in the September 2008 Linux Magazine about correcting color casts with a Perl script, and light dawned. I don't normally use Perl, but with your excellent template, I was easily able to write a script that does the necessary scaling and cropping for my print jobs. I also wrote a script for easy web optimization of my own digital photos. All of this has resolved a seemingly major hurdle, and I thank you for it. Yes, I do acknowledge your article in my Perl header, just in case anyone should ever see the script.

Bob Ackermann

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