Letters to the Editor

Readers sound off.
From the Wilds of Florida...

Ye brave souls at the Journal:Perhaps it was the pioneer spirit of Linux that first caught my attention. Maybe it was the sense of computing in the wilderness with no official support from the creators. It could have been the opportunity to mangle the source code beyond any recognition. Or was it the 'subtle' marketing campaign in .signature files that read, “I use and recommend OS/2 and Linux; 32-bits and Microsoft-free.” Nope, it was the price; free. Free is good. Besides, when did calling IBM or Microsoft do any good? Real computer users solve their own problems or get help from the net. But since free required a full Internet feed that is unknown in this part of the Union, I allowed Walnut Creek to sell me a CD. Well, it wasn't free any longer, but I don't think that makes any difference, does it?

Well, Yggdrasil slipped a tiny subscription card into the back pouch of the manual. In fact, it was your subscription card... So I scanned the Unix conference at Mac's Place BBS and found a positive comment and no negative comments. I see that you are also engaging in a subtle guerrilla marketing campaign.

Please start my two-year subscription immediately! No, don't take a coffee break! DO it NOW! Trust me, it won't take long, it barely hurts, and you might even enjoy it... Well, ok, finish the letter first...

Which brings me to a special request... I have this friend... He's a good person overall, but a bit of a slacker... And I think he would enjoy your magazine. But if I allowed him to borrow any of my copies, they would disappear into the chaotic vortex of pizza boxes, aluminum cans, and tractor-feed printer paper that defines his world. So, would you please send me an additional copy of my first issue? I guess we could call it a 'concurrent' sample issue for a subscriber, couldn't we? I knew you'd understand...Richard K. Evans, rk.evans@cfactory.com

Glossary Needed?

Yesterday I subscribed to Linux Journal. I haven't read the entire Journal as yet, but I do enjoy Phil Hughes' writing. Bernie Thompson has a clarity that is easily understood, and I congratulate you folks for the presentation of subjects that are not easily communicated.

Page 29 of the July issue reads “The Open Development of Debian”, by Ian Murdock. This one page is well beyond my understanding. I suspect Debian is some kind of perturbation of Debra and Ian, and the fully cocked and loaded Linux folks probably well understand these developmental pseudonyms, but if you're looking for a broad support for Linux, I and others will need to understand these terms. Where do you go?

Maybe a glossary in the Linux Journal that is appended to by the authors as these terms develop, or maybe a complete definition of the terms in the article.George L. Clute, geo@aircarg.celestial.com

LJ Replies:

A glossary won't fit, but we do intend to define terms that need defining. Letters to the Editor help tell us which terms need defining. In the future, the Debian column will include a sidebar (or something) which explains what Debian is.

Linux Domain Names Usurped

Dear Sir,I would like to register my deep disapproval of the actions of Aris Corporation in registering both the Internet domains 'linux.net' and 'linux.com' without any consultation with the Linux developers. This kind of action, which is equivalent to me setting up something like linuxjournal.com without your permission, does not appear to be of benefit to the Linux community.

The Internet naming is already the source of several battles over this kind of thing and one lawsuit (Adam Curry versus MTV). The Linux community getting involved in this only makes things worse. A sensible linux.com domain holding any company working with Linux could have been created. Now we are at the mercy of whatever Aris Corporation decides to do with that domain.Yours, Alan Cox

Reader Tips for Directory Tree Cloning

Dear Editor,I enjoyed the SysAdmin column in LJ #3. I wanted to pass on a tip that could save some time and trouble when cloning a directory tree onto a new filesystem. The article had us save the current file tree in a tar file and then remove it. This requires lots of extra space for the tar file, space that just may not be available.

Instead, assuming my new partition is /dev/hd5 and the directory I want to move is /users, it can be done like this (# is the root shell prompt):

# cd /
   # mv /users /users.old
   # mkdir /users
   # mount /dev/hd5 /users   # new partition ready
   # cd /users.old
   # tar -cf - . | (cd /users ; tar -xpf -)

The last step is the crucial one. The first tar sends a tar archive of the current directory tree to standard output. The parentheses enclose actions done in a subshell. The subshell changes directory to the new filesystem and runs a tar there to extract the tree from standard input. When done, the usual sequence of actions is

        # cd /
        # umount /users
        # fsck /dev/hd5         # for safety
        <do a fresh backup of the file system>
        # mount /dev/hd5 /users
        # rm -fr /users.old     # kerbam!

This trick with two tar commands in a pipeline was documented in the original tar(1) man page; it has not survived into the current tar(1) for all Unix vendors. I hope this letter will help save some time and trouble for anyone needing to copy directory trees.Arnold Robbins, arnold@skeeve.ATL.GA.US