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Letters to the Editor

Slackware to Debian

...I read the article ``Is Linux Reliable Enough?'', by Phil Hughes in the July 1997 issue. Mr. Hughes indicated that SSC is using Slackware 96, but is changing to the Debian distribution. Here are a few questions:

1. Why are you considering a change to Debian?<\n> 2. Is there a problem with the Slackware 96 distribution?
3. What are the advantages/disadvantages of Debian?
4. What are the advantages/disadvantages of Slackware 96 and other versions?

I would also like to see articles on the following if it is possible:

1. Comparing the RDBMS products such as Solid, Empress, mSQL, Postgress and etc products.
2. Comparing the Motif and other GUI development tools such as Xforms.
3. Many articles stressing the important uses of Linux in the Real World.
--
Edmund P. Morgan
Senior Software Analyst
Emorgan@cup.net

While Slackware has been reliable, its upgrade management tools are lacking. Debian (and Red Hat) offer an installation system that includes dependencies. In addition, Debian offers a menu choice to upgrade all installed packages. When you are managing the software on 25 systems, good configuration management can save you substantial amounts of time. We are planning to do an article comparing the various distributions next year in our June issue.

You must be reading our Editorial calendar for next year: our focus for the February 1997 issue is databases, for March, it is GUIs and for April, it is Business Solutions. In past issues we have done reviews of most of the databases as well as addressing GUI development tools; we have also covered Tcl/Tk and Xforms and present a monthly ``Linux Means Business'' column.
--
Phil Hughes, Publisher
phil@ssc.com

LJ Cover on Education

I was on your web page and saw the cover for the October Education issue. I was a college professor when I felt my life most had meaning, and because of that, I always enjoy working with college students. Your cover brought that feeling home to me again.

It looks like a good issue, and I expect to enjoy reading it.
--
Jon ``maddog'' Hall
maddog@zk3.dec.com

My First Issue

Yesterday I received my first issue of Linux Journal in my mailbox. I have not put it down since. This is the best source of information for Linux I have found. I run a production Linux network/Internet site, and I am always looking for information about new tools and other Linux information. LJ has already helped me solve the problem of how to monitor my Linux servers. I've been using Linux since 0.99.something and have completely converted from other partial Unices. Keep up the good work. The only thing I can see that would help LJ is if it came out once a week instead of once a month. I can dream...
--
Darren Young
youngd@cirrusnet.com

Bridging the Generation Gap

My parents just left with two copies of Linux Journal (#38 and #39, #40 appeared in the mail today)--in spite of the fact that up until now, they have only used MS-DOS for their computing needs.

In Dutch we have this proverb: ``Je bent nooit te oud om te leren''--you're never too old to learn. So, who knows ...
--
Toon Moene, The Netherlands
toon@moene.indiv.nluug.nl

Choices

After reading Mr. Temple's letter to the Editor in the August 1997 issue, I must disagree. The popularity of Linux has exploded in the past year, not because of people who want to see how a true preemptively-multi-tasked operating system works, but because people want to use this operating system to accomplish tasks (i.e., real work).

I can find my way around a kernel; in fact, hacking the Minix kernel was required in my Operating Systems class in college. However, my main interest in using Linux is to do my job. To that end, I've used Linux on a surplus 386 SX/20 to build a company firewall/gateway and e-mail server/router. Using IP masquerading, sendmail and a few custom Perl scripts, this throw-away machine is now responsible for routing both incoming and outgoing e-mail and for firewalling our Intranet over a single dynamic PPP line. To me and to a lot of other readers of LJ, networking is the main draw to Linux. One of the beauties of Linux is that it has something for everybody.

Keep ``Kernel Korner''--I read it--but keep on including the networking articles. Linux is too diverse for LJ to resemble PC Magazine.
--
T.J. Harrell III
harrell@navajo-refining.com

Webmaster Handbook Idea

As an avid reader/subscriber to LJ, I've been collecting your articles related to webmastering and running a network/web server. This spans the gamut from creating/using CGI scripts to how to use ``TCP Wrappers'' (August 1997). I've got quite a selection now, and it's occurred to me that others may have the same need.

So, may I suggest LJ package reprints of all the pertinent articles from years past, add an index and perhaps some advertising, then sell it for a reasonable/nominal price, perhaps $5.95US (myself knowing nothing about the publishing, especially the money).

As an alternate, perhaps you could put up a page on your web site with an index to the articles, with each a link to a summary page or the actual text, if available. This might encourage people to then buy the back issues.
--
Scott Daniels
scott@blueghost.npt.nuwc.navy.mil

I'll put it on the ``wish'' list. We do put articles on the web site after a time, but it's never certain as to when someone will have the time to do the HTML. We are also planning to start putting past issues on CD-ROMs and sell them in that format. The 1996 issues are in the works now.

Lotus Notes for Linux

Half a year ago, I'd asked on the Caldera mailing list what kind of applications people would want on Linux that weren't yet available. The two most-requested applications were an accounting package and Lotus Notes. With the Appgen announcement, one of those is now covered. As for the other...

I was in conversation recently with someone who has been talking to IBM (at an appropriately high level) about porting Notes to Linux. That person told me that any testimonials about potential end-users who would buy Notes for Linux would be instrumental in convincing IBM to make it happen. There are no technical issues; this is only a matter of marketing and convincing the sales folk.

While I have no use for Notes, I believe its availability for Linux would be both an important application and yet another validation of Linux's suitability for corporate use.

Please e-mail me any relevant information and I promise to pass it on ASAP--added to a few stories of my own...
--
Evan Leibovitch, Ontario
evan@telly.org

Really Push League

I read Doc Searls article, ``Shoveling Push Media'', in Linux Journal, June 1997. I threw out my TV six years ago; if push ever comes to shove, I'll do the same with my computer systems, too.

I've been in this business for fun and profit since the days of CP/M, designing circuit boards, programming, etc. and on the Internet for about a decade.
--
Max Southall
max@prninfo.com

Zombie Processes

In the August 1997 issue (just received), I have spotted what I believe to be an error. On page 40, In the column ``Best of Technical Support'' there is a footnote to the paragraph headed ``Mysterious Zombie Process'' which states, ``When a parent process dies or is ended, any child process started by the parent becomes a zombie process.''

The condition described is that of an orphan process, not a zombie. Orphan processes are created when their parent process terminates, and all orphans are automatically adopted by the scheduler process (process 1).

A zombie process, on the other hand, is any process that has terminated but not yet been cleaned out of the process table. In some of the original Unix literature from the folks at Bell Labs, they comment that a zombie process can only be resurrected by the use of arcane magic.

In the voodoo religion, a zombie is a dead person who has been reanimated via magic, so the appellation when applied to a Unix (or Linux) process is not quite appropriate, but it comes close.

As to the problem experienced by Scott (the author of the note), I would venture to guess that the process he is invoking (netcfg) performs a fork( ), exec( ) combination, and the parent process then exits. This is a typical hack used to prevent the invocation of a program from hanging up the terminal if the user forgets to use the & character to run it in the background.

Since the parent has terminated, the terminal is again available for command input. The child process will still be running in the background, however. For whatever reason, the parent process is not able to be cleaned out of the process table (perhaps until the child processes all terminate?), and so it shows up as a zombie.
--
Harry Gross
harry.gross@ix.netcom.com

The footnote in question is almost a direct quote from ``Unix: An Open Systems Dictionary'', William H. Holt and Rockie J. Morgan, Resolution Business Press, 1994. This dictionary also defines an orphan process as being synonymous to a zombie process. I wanted something short for the footnote, and the Dictionary gave me that sentence--perhaps, I need to buy an updated version.

U.S. Domain

In regard to the article, "Registering in the U.S. Domain (For Free)'', by R. K. Owen, July 1997, the title is very misleading. The era of free US domain registration is over. Most of the incorporated cities of the US domain have been delegated to entities which usually charge a yearly fee for registration and maintenance.

The assignment of delegation was done by Jon Postel and done without any public notification or bidding on administrating. That is, there is no indication of why an administrator acquired the domain, but whoever they are, they have no reason to not charge any amount they wish.

Those domains not covered by incorporated cities, which are still administered by ISI direct will shortly be farmed out as well, as Postal claims ISI (Information Sciences Institute, USC) is shutting down such services.

Even worse, previously delegated domains down to one's own personal name are transferred, and those now holding such domains may be liable for the fee or lose their database references.
--
John Clark
jclark@cts.com