Sat, 14 Apr 2012
My New Bike
Several months ago, I have written about choosing a new bicycle. Here is the outcome:
Introducing my new AZUB Apus. I have rented and extensively tested several recumbents from AZUB (20" Eco with above-seat steering, 24" Max with under-seat steering, and 26/20" Apus with above-seat steering), and I have decided to go for Apus with under-seat steering.
The next thing to decide was gearing. After testing 24" Max with 48-38-26 chainrings and 11-34 sprocket (about 570% ratio) I've got the feeling that I could occasionally use even slower gear (and with 26" rear wheel of Apus the 26/34 gear would be a bit faster than on a 24" wheel), and I can definitely use more faster gears. Recumbents are fast, especially going downhill, because of lower aerodynamic drag. So I wanted gearing with ratio larger than 570% and with the slowest gear slower than 26/34. This is hard to achieve with current components, so I went for triple gearing: I have got SRAM DualDrive in-hub planetary gearbox (three speed gearbox and 8-speed derailleur), combined with tree chainrings, giving me 3x3x8=72 gear combinations and over 920% ratio. One of the biggest advantages is that the gearbox gears can be changed even without pedaling, for example after having to stop unexpectedly.
After five months with Apus, I am still excited with it. I really enjoy being faster on flat surface and on downhills, being able to pedal even while turning, having excellent view with zero neck, wrists and backbone pain, being able to brake without the danger of falling ahead, sitting lower in case of fall, and so on.
The drawbacks are worse view when entering street crossings, being slower uphill, and not being able to jump over obstacles higher than about 10 cm). And the front suspension of the SASO carbon fork is not as good as I expected. I plan to try softer coil spring.
If I had to choose again, I would buy the same bike, possibly with not-so-steep sprocket (11-28 instead of 11-32). Also, having used really narrow tyres on my previous (road) bike, I did not pay much attention to the brakes - I have got V-brakes on my Apus, and I am not able to make the front wheel slip even when braking really hard (on asphalt roads). So probably next time I would get disc brakes instead (at least on the front wheel). Anyway, watch this guy's commute riding Apus on forest paths:
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Fri, 18 Nov 2011
Google Authenticator
For some time, I have been considering adding two-factor authentication to my systems in order to prevent break-ins in case somebody's workstation is compromised (which is a common attack vector these days). One of the systems for one-time passwords is Google Authenticator.
G-A has an application for many smart-phone platforms (Android, iOS, Blackberry), and has a PAM module, which is even packaged in Fedora. It stores users' secrets in a file in the home directory, and uses 6-digit time-based passwords and 8-digit emergency scratch passwords. The configuration in Fedora is pretty straightforward:
yum -y install google-authenticator- In
/etc/pam.d/system-authandpassword-auth, changepam_unix.sofromsufficienttorequired, and after that line, add the line which reads "auth sufficient pam_google_authenticator.so". - Install the G-A application to your smartphone.
- Generate a new key using the
google-authenticatorcommand. - Add the key to your smartphone, either directly or using a QR code.
- Profit!
There are several problems with SSH-daemon, though:
- With SElinux enabled, it does not work.
- When public key authentication is allowed in
sshd_config, it also does not work (use "PubkeyAuthentication no" in/etc/ssh/sshd_configand restartsshdif you want to test it).
Especially the second problem is pretty serious, as I wanted to allow also public key + one-time password authentication there.
So, my dear lazyweb, what kind of two-factor authentication do you use?
2 replies for this story:
Adelton wrote:
Dan has just released post to his blog at http://danwalsh.livejournal.com/48161.html -- I did not dig deep whether it solves or just reiterates the SELinux problem thou.
Yenya wrote: Re: Adelton
Yep. The SELinux team has definitely the best response time (and attitude!) in Fedora bugzilla. There is further discussion ongoing in this BZ entry. For all interested parties, I suggest to continue discussion in that BZ.
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Mon, 03 Oct 2011
Dear Customer,
[...] we would also like to inform you about the following change
in your network: a new address has been assigned to you:
2001:4cc8:...::/64.
Netbox apparently supports IPv6 now. Yay!
2 replies for this story:
dan wrote:
I got that e-mail as well! I've got to try it, hopefully it's not an error in the matrix :-).
Cohen wrote:
https://konto.netbox.cz/sco/network/ipv6
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Mon, 18 Jul 2011
Which Bike?
The 30 years old frame of my bike broke several weeks ago, so I will need a new bike. We have already decided to buy a new bike for my wife, so I have took the frame of her present bike, and remounted some components of my former bike to it. So I don't need a new bike right now, and I have more time to decide what I want.
My previous bicycle was road bike with drop handlebars. I ride on paved roads mostly (altough many roads in Brno resemble off-road riding :-), and we occasionally do touring as well. I am considering the following options:
- Using the frame of my wife's bike until it breaks :-)
- Buying a cyclo-cross bicycle, which is essentially a road bicycle with hardened frame and different tires.
- Buying a touring bicycle, something like Author Avion, which even has a carbon frame.
- Something really different. Last week I rented a recumbent bicycle, AZUB ECO. It was really interesting, very comfortable, yet a bit difficult to drive. I would like to try a bigger one with under-seat steering, like AZUB 5 as well. The only problem with recumbents is that it is not possible to use them with trail gator tow bar.
So, my dear lazyweb, do you have anything to recommend?
7 replies for this story:
Vašek Stodůlka wrote:
I have a scooter (koloběžka in Czech :-) model "Street" from Kostka, it is extremely handy in manipulation, it fits into sedan car boot without any diassembly. It is fun to drive with kids, when they have their own bycicles / trikes, it is possible to use it when others are roller-skating - you have similar speed about 16km/h. It is difficult to use it for longer trips and maintaining higher speeds, because it does not have any transmission. It is not a substitute for traditional bike, but it is very entertaining. A friend of mine has recumbent trike - azub also make theese. For me it looks like more fun, than bike, but on the other hand it is also less useful offroad. And when it comes to traditional bikes, anoher friend of mine (Aleš Habáň) has a shop in Brno - http://www.habbybikes.cz/. I think he is very experienced and can give you advices and if you tell my name, he may give you some discount. ;-)
Honza Obdržálek wrote:
Thinking about a CX bike, you may know that the differences include a slightly different frame geometry and brakes, which are weaker than the standard road bike brakes (if you do not go for the recently allowed disc brakes). The wheels are basically the same as for road bike, the only difference being the tyres. For the uses you specify (city + some touring) I do not see a point of buying a bike with drop handlebars. The "touring bike" you link is not really a touring bike (i.e. trekking bike) but a cross bike (the difference being the former usually comes with mudguards, pannier rack etc.) Cross bike can actually even lack attachment points for a pannier rack and mudguards. Note that in this price category you do not get much extra by having a carbon frame. For the uses you specify I would, however, buy a bike with a rigid fork (you save lots of weight, cheap suspension forks are useless, and you do not really need the suspension). Here I would recommend a carbon fork. As for recumbents, I'm having my reservations for use in traffic - you are too low to have a good situation awareness.
Yenya wrote: Re; Honza Obdržálek
Thanks, Honza (and sorry for my incorrect terminology). As for situation awareness with recumbent, after having ridden a recumbent for four days, I think it is actually better than on a regular bike, with one exception, and this exception has nothing to do with sitting too low, but with sitting "in the back" - when I enter the intersection, on a regular bike I am head-first, and I can see much better than on a recumbent, where I have to move much farther to the crossroads before I can see the situation.
Yenya wrote: Re: Vašek Stodůlka
The Kostka Street looks definitely interesting, but I am afraid it is not suitable for me - one of the purposes of my bike is commuting to work, which is about 8 kilometers with relatively steep hills (from Hády to the level of Svitava river, then uphill to the level of Mendel university, and back to the level of Ponávka). I don't think I would be able to enjoy it on Kostka.
Tom wrote:
I've recently bought Mongoose Croix Elite and I'm quite happy with it. (It was 2009 model which I ordered, but 2010 model actually arrived. Well, there's probably not much of a difference except for the price :) Anyway, what I intended to get was something close to a road bike which I wouldn't be afraid to use in light terrain. And after I switched to slick tires (35 mm wide, 6.5 bar max pressure) it pretty much fulfills my expectations, though I don't have that "light" feeling of a road bike completely, which I guess can't be achieved without those thin, heavily pressurized tires. There are V-breaks which I do not find to be insufficiently effective -- it's not a problem to block the wheels, and I personally prefer drop handlebars which you can hold in many ways. I also use the bike for commuting (Lesná Gorkého) and it's alway a pleasurable part of a working day :). So I would probably go for a CX bike rather than some normal cross bike.
J.C. wrote: Option 1
I suggest option 1, the easiest one ;-). You will have enough time to consider the other possibilities.
job wrote:
i use to room in my bicycle but i brought my first motorcycle. my bike is sleeping for years :(
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Wed, 15 Jun 2011
High-Performance HTTP Servers
Yesterday I have read about Apache Traffic Server. My dear lazyweb, do you use something like that (or Nginx)? What is your main reason for using it? I wonder why use user-space solution, when IPVS works pretty well for load balancing.
1 replies for this story:
Miroslav Suchy wrote: Perlbal
I used to use Perlbal as reverse proxy server. Why I did not used some kernel module? User space is much better for maintenance. At least for me. I can create new instance of Perlbal in 5 minutes and it will not require maintenance ever. I could not say that for kernel modules as I'm upgrading kernel whenever update from distro come.
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Fri, 03 Jun 2011
Citroën Xsara
It has been seven years since I have bought my Citroën Xsara. At that time, I have considered several models, looking for an estate car for my family. Having used several Škoda Felicia cars in my previous job, I have definitely wanted a car from some other manufacturer. My opinion was "the car can have its problems, but at least let it be different problems than Škoda have".
That said, I have never considered Citroën, and in fact I did not know much about Citroëns. When I have been offered a 4.5 years old imported Xsara, however, I have found it "good enough" for me to buy.
Subsequently, I have been pleased to find out how comfortable my Xsara was, and how well equipped compared to the cars of similar age and class it was. It provides enough leg room in back seats (especially when compared to Octavia), and the 82 kW engine provided enough power for most of my needs. During almost 100,000 km in seven years I had only few malfuncions, the most serious one was a broken exhaust pipe because of corrosion.
Even though I did not originally considered buying Citroën at all, the next car which I have bought and which I use these days is also Citroën. So, my dear lazyweb, is anybody in your social network interested in buying a cheap, well-equipped, used car? If so, look here.
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Tue, 24 May 2011
Mysterious Source Code
About a month ago, I have spotted a two-page listing of source code in our printer room/kitchenette. I have glanced over it briefly, and during subsequent visits to the room, I became more and more fascinated by it. Finally, about a week ago, I have grabbed it for myself, because nobody seemed to care about it anymore. So here it is, in all its glory:
Click the thumbnails for full-size images. Sorry for not providing a plain text version, and sorry for the Czech language in the comments. I have two reasons for which I find it really fascinating:
- There are two pages of source code, which does literally nothing. It only wraps an existing class with a new one with marginally different API (two exceptions joined into one exception, and retrying in case of failure). Nobody sane would write these two pages by hand, so I expect the code has been at least partially generated by some IDE. Obviously nobody can expect the code to be read by a human (actually, not read, but carefully examined for traces of some non-trivial application logic, should there be any). So I wonder what the present meaning of "the source code" phrase is, when it is no longer written nor readable by humans.
- The only real "application logic" is the
for-cycle near the end of the second page. And even this has been totally destroyed by the "every block should have only one exit point" mantra of the programming theoreticians. Adding a simplereturnstatement when the message sending finally succeeds would save them the following:- a boolean variable
- a complicated condition in the
for-cycle - an
ifstatement when the maximum number of tries is reached
I can only hope this is some kind of a silly example and not a real assignment given to the students of the Programming in Java course. I think the students have to be taught that mid-layers are root of all evil, and not some highly theoretical (read: impractical) rules like "goto is evil" or "a single exit point only".
4 replies for this story:
gRis wrote:
I would have said it is a code snippet for the Public Administration Informatics guys, but it reminds me too much of the atrocities we used to create in PB162 several semesters ago. I suggest you ask in the course discussion forum, or submit it to TDWTF.
himdel wrote:
Nope, this was an actual PB162 homework, I remember having to write something very similar. Courses like this are what made me really despise Java (I don't, anymore, but I still think it's rather silly). However, IIRC it was meant to teach about chaining exceptions, which it probably does well. And while they might have taught the single point return nonsense, there were only automated tests so the student who wrote that could have written it better.
EL wrote:
Having taught Java (meaning I was the "teacher" on the excersises for two terms) I'd say that this is just silly looking excersise, with empasis on the word looking. My guess is that this is a way to teach students how to use exceptions (which you have to do a lot in Java). Normally, on such a small piece of code, you wouldn't bother, but this is how the students IMHO get used to the exceptions. BTW: While I understand the "old programmers" desire to minimize the amount of variables etc., from my point of view there are two most important things that should be considered regarding a source code: - readability (that includes consistent coding) - the best available complexity (in the terms of computational complexity) So in this case, the return would definitelly make more sense than the overcomplicated condition, but the (non)existence of the boolean variable doesn't seem so relevant (although it vanishes from the code as well as a result).
EL wrote:
Ooops, sorry for the (non)formatting, I tought it would be preserved.
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Mon, 23 May 2011
Lost GUI features
Contemporary GUI applications have several problems which, if I remember correctly, previous systems did not have. I wonder whether somebody else also considers it being a problem:
- Creating a new file
- Almost every TUI text editor (like
vim) happily accepts a non-existent file
as a command-line argument, and the straightforward interpretation is
"user wants to start working with a new file". On the other hand,
most GUI applications simply complain that the file does not exist,
and some‒like OO.org‒exit after that
message. Other GUI apps,
like Gnumeric, present
a warning, but then open a new work with the default file name
(
Book1.gnumericin the case of Gnumeric) instead. - Working directory
- The file open/save dialog of contemporary GUI apps does not offer
by default the working directory from which the application has been started,
and uses some silly default (such as
~/Documentsin case of OpenOffice.org). Even gThumb needs to be explicitly told that the user wants to browse the current directory with the "gthumb ." command line. - Iconified applications
- Once upon a time, in a stone age of GUI computing, there was a twm window manager. When the application window was not needed on the screen, twm could be used to iconify the application. All applications, and all instances of them, could be iconified and then restored back the same way. Then Windows 95 happened, and it started to minimize the applications to the bottom panel instead of iconifying them to any place in the desktop. It also reused the desktop icons as application shortcuts instead of representing the minimized running applications. Unfortunately, the panel was too small for so many running minimized applications. Users stopped expecting to be able to restore the application after minimizing it. The applications which required to be minimized and restored back frequently (music players etc), developed their own means of minimizing, the notification icon area. So we have the iconification back, only not usable from all applications, and with each application implementing it in its own crappy way.
So what other important features of the "desktop of the past" do you consider missing from the present GUI systems?
UPDATE 2011/05/23: Iconified Apps
I have just discovered that XFCE4 in Fedora 15 allows the desktop icons
to be switched between the Application launchers/shortcuts and Minimzed
applications modes. Yay!
8 replies for this story:
Jiri Appl wrote:
Actually KDE apps still adhere to the first two points. Or at least kwrite and kword do. As for the iconified applications, kwin supports showing only the title bar of a running application.
Jiri Appl wrote:
Actually KDE apps still adhere to the first two points. Or at least kwrite and kword do. As for the iconified applications, kwin supports showing only the title bar of a running application.
Obvious Troll wrote:
Well, why don't you go and fix it? It's not like they're Microsoft apps, right? ;-) On a more serious note, I completely understand your frustration. I have to spend hours fixing (i.e. reverting crappy GUI decisions) applications every time a major release comes out. It feels as if there were some saboteurs writing bad code to make us switch to commercial software. I already did that in the case of Microsoft Office.
Yenya wrote: Re: Obvious troll
Why don't I fix it myself? Well, I expect the said behaviour is intentional so the patches will not be accepted. And I don't want to fork it. As for MS Office - their Ribbon UI is a prime example of what I _don't_ want to use.
Obvious Troll (not anymore) wrote: Re: Yenya
I am not convinced that it's entirely intentional. To me it seems more like something no one thought or cared about enough to fix. Anyway, you could either make it an option in settings or, in the case of creating a new file, turn the alert into a dialog. Regarding MS Office, I still have the pleasure of using the old UI as I have Office 2003. I wish they left the old UI as an option, but apparently one just _can't_ have it both ways. Anyway, the features are more than enough for the work I do and as long as there is some backward and forward compatibility, I should be fine. Maybe the problem lies not in the fancy new UI, but within us. Maybe we're getting obsolete almost as fast as our computers, and are being phased out by the young and progressive users. And maybe I should grab my cane, take out my false teeth and end this rant :-)
Milan Zamazal wrote:
IMO a sane user uses OO.org just as a document viewer or to edit (when being forced to do so) documents delivered to him. So complaining about a non-existent file makes sense to me. It's not a bad idea to use separate directories for different purposes so it makes sense to offer something else than cwd (that is typically $HOME) as the default directory. Of course, a civilized application should be extensible and so the default directory should be settable to anything (including cwd) by the user but that's another problem. As a user of an extensible tiled wm I don't understand why to waste screen space for either window bars or any kind of icons. A music player definitely doesn't require to be "minimized", my wm simply puts it automatically in its own workspace bound to a given hot key and the most frequent player operation (play/pause) is bound to a multimedia key on my keyboard without the need to display the player at all.
Yenya wrote: Re: Milan Zamazal
IMO tiling WMs suck. The main problem with them is that they resize xterms, and I want my terminals to have exactly 80 characters width. Another problem is that without window decorations, it is not easily visible which window has focus (which is also my objection to most themes of the non-tiling VMs; some of them display focus state only by changing the title bar, not the whole decorations). And music player in its own workspace? Having to switch to that workspace every time I want to do something nontrivial with it? No way.
Milan Zamazal wrote:
Tiling WMs are not for everyone, but they don't waste screen space and your complaints about them are invalid. If you always use the same font for your xterms, you can arange your workspace to make them 80 characters wide. Or you can use a floating window group (workspace). You can customize frame decorations to make the focused frame more visible if you want. I don't understand what's the problem with switching workspaces, you just press a hot key to switch to the player's workspace and another hot key to switch back to the original workspace. Don't forget that tiling WMs are based more on logical than visual concepts – and it's not easy to get free of some stereotypes (my own experience).
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Fri, 20 May 2011
GNOME 3
After installing Fedora 15 in a virtual machine, I have decided to give GNOME 3 a try. Firstly, it is really slow over VNC. While GNOME 2 has been pretty usable for testing various new applications in a virtual machine, under GNOME 3 it is almost impossible. Here is a screenshot on which I will demonstrate my problems with GNOME 3:
Firstly about the file manager. I use mostly command line for managing
my files, but using a file manager is sometimes handy nevertheless. One
of the features I often use is the "Places" list. In GNOME 3, it is presented
differently in the Places menu and in the file manager itself, which
is a clear usability bug. When I wanted to add another directory there
(I often use ~/tmp as my sandbox),
it took me at least 10 minutes to discover
that "Bookmarks" is what I probably want. And even then, the newly added
bookmark is added to a submenu instead of the main Places menu.
Also, I did not found any way how to remove those useless predefined
directories like Videos, Music, etc.
from the left sidebar. Even when I have deleted them from my home directory,
they still remain in the sidebar.
Another ugliness is that the new window manager does not decorate the windows properly, and instead relies on the applications themselves to provide things like resizing handle in the lower right corner (see the gnome-terminal window). Not only it looks ugly as hell, it also obscures the space the application expects to be visible. I will probably file this as a bug report when F15 is officially released, but I expect in a truly GNOME-ish fasion it to be solved by removing the "scrollbar on the left side" option :-/.
Anyway, it seems that XFCE+Sawfish combo works as expected, so I am definitely leaving GNOME when I install F15 on my workstations.
6 replies for this story:
thingie wrote:
You don't get "real" Gnome 3 without GL compositing, the new WM (not this one) needs it. It is quite different from this and it also has a new panel, without "Places" or "Applications". Given that even "ordinary" 3.0 is still rather incomplete, it's no wonder that this fallback environment is lacking even more.
Vašek Stodůlka wrote:
My desktops were Afterstep (doen not seem to be alive) - Windowmaker (similar) - waimea 0.4 (furter version were totally something else) and then went to gnome. It was not great, but everything worked and I liked the GUI simplicity. Now it looks also to xfce migration, or maybe I will go back to Afterstep, just for fun. I liked downloading plugins as source and coppiling that tiny-lovely one file binaries. I feel like i want to go back to the roots for a while.
Karel Zak wrote:
yum install cdargs ... for command line "bookmarks".
Yenya wrote: Re: thingie
I stand corrected, thanks! I have tested a real GNOME-3 on a physical machine (my wife's laptop :-), and after using it briefly, she is also migrating to XFCE now. For me, GNOME-3 looks like a smartphone/tablet UI - oversized title bars and scrollbars are the prime example of that. BTW, does anybody know how to add my own program/script to the list of favourite applications? Do I have to write the .desktop file for it?
Yenya wrote: Re: Karel Zak
Karel, I can manage my command line pretty well, thanks for asking :-). What I wanted was to have ~/tmp in every file/save dialog.
Yenya wrote: Re: Vašek Stodůlka
What I liked on GNOME-2 was the integration with hardware - it was usable even for my parents. Also the file manager was pretty good. For the first time after many many years I have used a GUI file manager when reviewing the documentation for the new faculty building. It was a three-levels deep directory tree with files named with mixed case, spaces and diacritics (often in more than one charset inside a directory).
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Tue, 03 May 2011
Rethinking Cron
cron(8) is one of the oldest tools in UNIX. Despite of that,
I think cron is not something to be proud of. In my opinion, it
falls to the unfixable designs
category.
The recent attempts to fix it (factoring out atd(8),
a dirty hack that is anacron(8), etc.) show some of the problems
of cron. My recent experience confirms it:
This is the load average graph from our server, which runs periodical jobs of
IS MU. Around 2 pm, I have rewritten the
main crontab joining several similar tasks to one line, and adding several
seconds delay between their startup. The groups of tasks are now started by a
simple Perl script which handles redirecting STDOUT and STDERR, and handling
the return code. The Perl script is started using exec in the
crontab line, saving one more process.
This way, I have managed to get the number of jobs which are
simultaneously started in the peak minutes of an hour from 155 to 13.
The system does exactly the same amount of work as before, but most of the
work is evenly distributed across the whole timeframe, not started in parallel
the first second of a minute.
This is one of the big weaknesses of cron. I think the future
cron will need to support the following use cases:
- Starting jobs approximately in a given period, but not exactly at the beginning of a minute.
- Starting jobs the given period after the previous instance has finished (and maybe warn if the previous instance keeps running for too long time).
- Run the job weekly, near the beginning of the weekend (not at some random
time as
anacronand/etc/cron.weeklydoes). See Fedora bug #671076. - Start a job several times in parallel (depending on number of CPUs or something like that), and restart them after some of them finishes.
What periodical and semi-periodical tasks scheduler do you use? Will
systemd
be the answer to these problems?
2 replies for this story:
Vašek Stodůlka wrote:
I miss the feature not to start when previous instance of the same line is still running. I use "lockrun" for this, but it is not a package in most distributions, so it has to be some better way...
xbezdick wrote: systemd
Lately when I was complaining about systemd somewhere I mentioned that it's already big enough to take over from cron and do even it's job...
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Fri, 01 Apr 2011
git-diff(1) Dark Color Scheme
The default colored output of git-diff(1)
and other commands is a bit ugly in my terminal with dark (green-on-black)
color scheme. Here is how to fix it:
git config --global color.branch.current 'yellow bold' git config --global color.branch.remote 'cyan bold' git config --global color.diff.new 'yellow bold' git config --global color.diff.old 'red bold' git config --global color.diff.meta 'cyan bold' git config --global color.diff.frag 'white bold' git config --global color.diff.commit 'white bold' git config --global color.status.added 'yellow bold' git config --global color.status.changed 'cyan bold' git config --global color.status.untracked 'red bold'
Hope this helps - I had to read the source code to find out where the color of the commit ID in git-log(1) is set. The above can at least serve as an example (after all, I don't expect you to have the same taste for colours), and for my future reference.
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Fri, 25 Mar 2011
man(1) Surprise
Hello, this is your editor speaking, welcome to the "lesser known Linux feature
of the day" series. Today we will cover an interesting feature
of man(1) that your editor has just ran into. Try running
the following command:
$ man git log
The manual page of git-log(1) is displayed on my Fedora 14 system.
How does man know that git
provides a "log" sub-command in addition to the equivalent
git-log standalone command?
The man page says:
By default, man will try to interpret pairs of manual page names given on the command line as equivalent to a single manual page name containing a hyphen. This supports the common pattern of programs that implement a number of subcommands, allowing them to provide manual pages for each that can be accessed using similar syntax as would be used to invoke the subcommands themselves.
And it even goes into an example using - guess what - git. That's all for today, see you next time!
2 replies for this story:
Adelton wrote: Not on F13
With man-1.6f-28.fc13.i686, I get man page for git and man page for log. Which version do you use?
Yenya wrote: Re: Not on F13
It is F14-only: man-db-2.5.7-7.fc14.x86_64
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Wed, 23 Mar 2011
XFCE
The first alternative to GNOME I have decided to try is XFCE. In the LWN discussion, Jon Masters presented it as a viable replacement to GNOME. Also, it uses GTK+ like GNOME, so many applications can be the same (including, I have hoped, my window manager of choice, Sawfish. XFCE is definitely usable and configurable for power-user. Most (but not all) properties can also be set using their Settings manager, and thus XFCE should also be mostly usable for ordinary users. So far the problems include:
- The keyboard configuration allows the user to set multiple layouts (for
example English and Czech/qwerty), but I did not find how to set layout
options, for example the layout switching hot-key. Adding a
setxkbmapcommand to the startup script is trivial, though (#5487). - The touchpad settings such as edge scrolling are not remembered
and cannot be set in the Settings manager. The solution is another startup
script, running
synclientwith the appropriate parameters (#5300). - The window manager cannot be chosen in a GUI. I had to remove the
default
xfwm4from the session and add Sawfish there instead (that said, I have nothing special against the default WM, I am just more used to Sawfish right now). - The Terminal application does not have
Ctrl +andCtrl -hotkeys for increasing/decreasing the font size (I sometimes use it, for example when more than one person is looking at the window). When the font size is set in the terminal menu, the physical window size remains the same, which means the number of rows and columns changes. Not good. I have solved this by choosinggnome-terminalin Preferred applications (#5605). - Moving applets inside a panel is not intuitive, and I have not found out yet how to reorder the launchers on a panel (#7142).
- Changing the orientation of a panel to vertical requires several non-trivial configuration steps. However, I have managed to configure the date/time applet (the only text applet on my panel) to fit a 48 pixels wide vertical panel, and I will probably keep the vertical panel orientation, as for most apps, the screen is more crowded in the horizontal direction (#7434).
XFCE is tightly related to both GTK+ and GNOME, and can incorporate various parts of GNOME (some notification area applets, keyring manager, etc). So I guess I would be able to use it as a replacement, if not for the whole GNOME, then at least for the central parts like GNOME Shell.
1 replies for this story:
davro wrote: multiple layout
xfce4-xkb-plugin (on ubuntu part of xfce4-goodies) does this.
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Tue, 22 Mar 2011
GNOME in the Shell
Yesterday, after reading The Grumpy Editor's GNOME 3 experience article at LWN, I have decided it is time to at least make an attempt to move away from GNOME, which (much like KDE 4) decided to use revolutionary instead of evolutionary development, and apparently continues in their feature removal crusade in the name of so called usability. Also, this might be a good chance to move away from Galeon after so many years.
I wonder what makes the GNOME developers think the existing users would
welcome a completely new desktop with very limited means of customization.
GNOME 2 has only recently reached a moderate level of usability (except
gdm, which is still not usable for many purposes since the
last rewrite).
It would be very sad to move away from GNOME, because I think I am not a typical conservative user, and I welcome occasional new features, provided they do not hurt productivity and power-user usability. However, apparently GNOME Shell provides neither, and the so called fallback mode is not complete enough (virtual desktops in a single row, seriously?). Also I would rather use the same desktop envionment as some non-computer-savvy users to which I occasionally provide technical support.
So I have decided to experiment a bit on my laptop, but keep GNOME and Galeon both on my home and work workstations for now. More on it in a few days.
Note: I am sorry, the above mentioned LWN article is subscribers-only for now. It will become freely available in several days. Alternatively, you can ask me for a link in a private e-mail.
2 replies for this story:
Petr Šabata wrote: Galeon
Just fyi, in case you still use Fedora: http://lists.fedoraproject.org/pipermail/devel/2011-March/149609.html
Yenya wrote: Re: Galeon
I have seen it coming. Even the current Galeon has several problems (focus loss, the "manage certificates" dialog cannot be closed after adding an exception, etc.). Yes, I still use Fedora and don't plan to move to another distro.
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Wed, 09 Mar 2011
New Odysseus
We have got a new hardware for our FTP server to replace our seven years old server. It is amazing how the old hardware is still in many aspects on par with state-of-the-art "average workstations". The old system had 12 GB of RAM, 8 TB of disks, and dual GbE. It was one of the first 64-bit x86 systems here at Faculty of Informatics. So, which principal improvements in server hardware the last seven years brought (apart from speed, of course)?
- Hardware virtualization is a standard now. This has allowed me to put www.linux.cz and www.cstug.cz to separate virtual servers, in order to tighten the security of the main server even more.
- Hot-plug disk slots are more-or-less standard now.
- Redundant power supplies. According to my experience, UPS-related downtimes are relatively frequent (be it scheduled in advance or not), and having one power supply in a circuit without UPS backing can help.
- Server management. Almost all server boards now have IPMI BMC on-board. The Tyan S2882 mainboard from seven years back had IPMI as a relatively expensive option, so we have decided to spend money on disks instead.
- Parallelization everywhere. The old Odysseus was one of the first x86 multi-CPU systems here. The new one has 16 cores, but only 33 % higher clock rate. The Neterion 10GbE card in the new server has 16 hardware queues, so it can keep all sixteen cores of the server busy (well, not exactly, because there are 8 RX and 8 TX queues, and our server does mostly TX, but it still helps).
Anyway, both the original and new configurations are described on the Odysseus statistics page (in Czech). Let me thank CZLUG and CSTUG for sponsoring some of the disks for the new server. We will see whether the new hardware can also keep running for at least seven years.
1 replies for this story:
petr_p wrote: IPv6
I can see ftp.linux.cz (odysseus CNAME) having AAAA record now. Great job.
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