Letters

Non-Linux Foss: MenuMeters?

Regarding Shawn Powers' Non-Linux FOSS Upfront piece in the March 2015 issue: MenuMeters? Hmm...that's pretty much the same thing as GKrellM (which has been around since forever-ish). GKrellM not only displays all the stuff on your working system but also on any of your networked servers with little, if any, fooling around. I've used it for years to keep an eye on the headless database servers sitting in the closet mumbling to themselves. I've also installed it on friends' Windows machines for quick and dirty troubleshooting and cores at 100% (ain't Windows wonderful, eh?). I don't know for sure, but I'll bet there's a version for Mac?

Sometimes the oldies but goodies are a pretty good choice, methinks.

—
Thomas

Thomas, yes, GKrellM is awesome, but there's not a readily downloadable version for OS X. (There is for Windows, however.) Honestly, the “Non-Linux FOSS” piece is one of the toughest for me to write, because most FOSS software that is available for Windows and/or OS X is also available for Linux. Finding non-Linux FOSS is...challenging!—Shawn Powers

Runtime “Stuff Happens”—Linux, Tell Me about It

I was pleased and interested to read about GNOME's pending enhancements to its desktop notification component(s). With so many things going on behind the scenes of a contemporary workstation, it is important to have effective (aka, “the right things”) and efficient (aka, “things done well”) ways to tell the end user that something happened. One might also hope that any such “telling” might also offer clues about what an end user might do as a corrective action or workaround for whichever “stuff happened”.

That's nice—where is the admin and end-user dispatch table that says, in part, “when EVENTx happens, do ACTIONx”, etc.? Why isn't this dispatch table as clean and obvious as /etc/anacrontab?

“Another tool suite” called systemd is causing a lot of chatter trying to do mostly the same thing—“do ACTION when EVENT happens”:

Decades ago, I worked on TOPS-10/TOPS-20 mainframes. There was a utility suite that 1) handled all of the notifications; 2) routed notifications to end users, operators or others who were on the lists to care about those notices; and 3) provided a per-user portal for trying to recover, correct or resolve whatever was going on. I'm all for innovation, but isn't it time we re-solved (sic) this feature set and move on?

—
Dan

Scale13x

I was listening to Kyle Rankin's “Tails” talk at Scale13x. Sitting in the third row, I heard a call for assistance on my two-way radio in another room; I was an A/V volunteer. I wanted to get up and sneak into the back of the room to exit so I didn't disturb the great presentation. Wow! When I turned around, the room was jam-packed with people sitting all over the aisle floors. I had to walk right in front of the room to exit. I hope Kyle didn't think I was bored with his presentation. I did have a shirt on that had “A/V Volunteer” written on it in big letters. I came back after a few minutes and Kyle had finished, and there was a crowd of people asking him questions. I hope he made it out of there okay. Most Linux folks are friendly though, and we did have a sense of community at the conference.

—
Roman

Quizzes

I thought it would be interesting to share these quizzes with you and your readers. At dcjtech.info/quizzes, I made some interactive quizzes about Linux that people can take for fun, practice, school or interviews. My Web site is ad-free, so it should not annoy visitors.

—
Devyn Collier Johnson

Cool, thanks for the link, Devyn!—Shawn Powers

Linux Newbie Request

I really appreciate Shawn Powers' enthusiasm and his approach to teaching Linux in the CBT Nuggets videos he's done for the LPIC 1 certification.

Currently, I'm in a software support role in LDN with descent bash knowledge, and my next step would be to move on to a system administrator career. Can you recommend any Web sites with LPI practice exams?

The Internet is packed with Web sites, but forum reviews are quite concerning, as many are scams, outdated, crippled with errors or have no support.

—
Patrick

I've found the folks at the LPI to be great to work with. I'd recommend contacting them directly (even via Twitter) for advice on practice exams.—Shawn Powers

Initializing and Managing Services in Linux

Thank you for the very informative and timely “Managing Services in Linux: Past, Present and Future” article by Jonas Gorauskas in the March 2015 issue of LJ. The following is a URL of a comparison chart of different init systems (yes, it's Gentoo-centric): wiki.gentoo.org/wiki/Comparison_of_init_systems.

—
Richard

Individual Contribution to Open-Source Project

Have you ever chronicled the experience of a software developer contributing to an open-source project for the first time? Some of the highlights could be finding a project, finding something to work on in the project, submitting work, responding to rejected work and first accepted work. Then as the developer becomes experienced, contrast getting involved in more projects, so as to describe how valuable the lessons learned were going forward.

—
Jon Redinger

That might be an interesting story. If you're offering, submit a pitch to info@linuxjournal.com. See linuxjournal.com/author for more information.—Shawn Powers

systemd

I always hated the init solution—System V Init is definitely something of an old technology. Therefore, I welcome systemd. It promises to auto-restart; support “new” technologies like USB, Bluetooth, storage devices and so on; and to support future technologies as well. It's a modern approach to tackle the current and future problems in services. There always are initial start problems with new technologies, but we shouldn't hold on to past technologies and lose the technology advantage we have with GNU/Linux.

“Managing Services in Linux: Past, Present and Future” by Jonas Gorauskas in the March 2015 issue was a good article! I advise Linus Torvalds to implement systemd as soon as possible in the mainstream kernel as the default service manager and drop the older technologies in favor of systemd. You could add a compatibility modus with the older one if it is necessary, but the way forward is systemd. The fact that it's implemented in Debian and Red Hat is already proof for me that it is good technology. Maybe this is a good time to change to a higher version—for example, 3.4 or 4.0—to indicate a major improvement in the kernel?

—
Patrick Op de Beeck

Question for Dave Taylor

I was trying to put together a simple script to recurse through a directory tree:

#/bin/bash

function recurse_dir()
{
    for f in * ; do
            #do stuff ;
            if [ -d "${f}" ] ; then
                    pushd "${f}" ;
                    recurse_dir ;
                    popd ;
            fi ;
    done ;
}

pushd ~/dir ;
recurse_dir ;
popd ;

When running this script, I got errors about invalid options. It turned out that some of the subdirectories had leading dashes (-) that were being interpreted as options. I remembered that it is possible to add a dash, or double dash, to turn off further option processing. Have you any other tips for dealing with difficult filenames? I think it is possible to have quotes in some, and that has caused me problems in the past.

—
Jeremy

Dave Taylor replies: That's an interesting script you're trying to build there, Jeremy. I'm not clear why you're using push/pop as you traverse the directories too. Why not just have cd ${f} followed by cd .. to get back up a level and simplify things?

In terms of difficult filenames, yes, Linux wasn't really written to deal with filenames that start with a dash, have a space or other punctuation, etc. The best you can do is experiment to see if the commands you're using accept -- as a way to delineate that you're done with command arguments, and quote the directory names themselves, as you've done.

Good luck with this!