2002.04_Brave Gnu World-the Monthly Gnu Column.pdf

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is plenty of music. Some more interesting levels are

also needed.

Help is wanted in many forms: developers are as

welcome as people contributing to sound effects or

more levels. Level design does not require

programming knowledge, by the way, since

everything is done with XML. The game itself was

written in C++ and runs under GNU/Linux. It may be

possible to also run it on other Unix-based systems,

but the developers are more interested in a Win32

port at the moment.

The immediate plan is to finish the Windows port

and release a new, completely playable version.

Afterwards multiplayer, as well as network support, and

a consistent storyline are needed to finish the game.

At the moment, the game can only be

recommended to users willing to play around with

half-finished games and who might like to contribute

parts to it.

Pingus under Mandrake

Welcome to another

issue of Georg CF

Greve’s Brave GNU

World. As this marks

the column’s third

anniversary you’ll

find a few words of

celebration as well as

some new projects,

but we’ll kick off the

proceedings with

another Free game

Pingus

Pingus is a game developed under the GNU General

Public License by Ingo Ruhnke, Giray Devlet, Cagri

Coltekin, David Philippi and Alberto Curro. The

game was inspired by DMA Design’s proprietary

game Lemmings, in which a player had to direct a

group of lemmings through perilous levels to the

safety of the exit. The only way to influence the

flow of the lemmings was to give some of them

special jobs, such as diggers, climbers or even

bombers. Pingus, as the name might suggest, lets

you do all these things to little penguins, which bear

a striking resemblance to Tux, the mascot of the

Linux kernel.

Game development was started in 1998 and after

an announcement on Slashdot, gained the input of

some graphically adept users, which gave Pingus a

very attractive look. The graphics even triggered spin-

offs like Xpenguins, which lets Pingus’ protagonists

roam the desktop.

At the end of 2000 development came to an

almost complete stop, but a year later some fresh

programmers helped overcoming this involuntary

pause. As it stands, the game is still not finished and

according to Ingo Ruhnke “it still doesn’t feel like a

real game”. This may also be partially because no

sound effects have been implemented although there

Process View Browser

The Process View Browser (pvbrowser) by Rainer

Lehrig provides a structure for process visualisation.

This is important in all areas where technical

processes are to be visualised or controlled. Examples

of proprietary programs performing similar tasks are

WinCC or Wonderware.

The project consists of a server and a browser,

which communicates with the user. Unlike in

comparable projects, all configuration is done on the

server-side. Users can modify the server according to

their own needs, i.e. they can write routines

interacting with the hard or software defining which

objects are to be displayed and controlled in which

way. These components are then displayed by the

browser according to the information provided by the

server over the network.

The programming language used for this project

was C++ with Qt as the graphical toolkit for the

browser and ANSI C for the server. The project is very

platform-independent: it runs on GNU/Linux as well

as under Windows or VMS. According to the

information provided by Rainer Lehrig, the browser is

faster on a 330MHz GNU/Linux notebook than on a

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1GHz Windows NT system, which he blames on the

networking code.

The platform independence is also linked to the

one downside of the project, which made me think

very hard about whether I should feature it in the

Brave GNU World. The Process View Browser is only

Free Software under GNU/Linux, for which it is

released under the GNU General Public License. The

project is proprietary under Windows and VMS.

However, two factors convinced me to write about

it in the Brave GNU World. First of all this area has

been dominated by purely proprietary versions until

now, so the project certainly takes a step into the

right direction. Also the user is capable of using it as

entirely Free Software as long as the GNU/Linux

platform is being used.

Additionally, the license-situation of the Qt toolkit

is very much comparable since only the X11-Version

is available as Free Software, while the Windows and

Mac versions remain proprietary. Since Qt is being

used by the Process View Browser, a Free Windows

version of the pvbrowser would not really help a user

since dependency on the proprietary Qt still remains.

Qt is a respected Free Software library under

GNU/Linux that is being used for many important

projects like the K Desktop Environment (KDE) and

has been mentioned in the Brave GNU World many

times already. So it seemed unjust to not mention the

Process View Browser because of a comparable

licensing policy. Hope remains that the versions for

systems other than GNU/Linux will also be available

as Free Software in the long term – a hope that

equally applies to Qt and the Process View Browser.

Rainer Lehrig has been working on the pvbrowser all

by himself so far and is now looking for others who

might be willing to help testing or contribute ideas and

code. Volunteers are also sought for documentation.

If you are interested in this field, please feel free

to participate in the Process View Browser. I

recommend only doing so for the GNU/Linux

version, however and authors of documentation

should take care to release it under the GNU Free

Documentation License or a similar license. Only in

these cases will it be reasonably safe to assume that

work contributed will continue to benefit the Free

Software community.

In order to prevent possible misunderstandings I’d

like to emphasize that the described problems do not

lessen the contribution of Rainer Lehrig to Free

Software. Bringing Free Software into a hitherto

proprietary field is always a very important task. Still it

remains important to be aware of the problems and

understand what they mean.

Process View Browser showing an image with widgets

January 2001 as PowerPhlogger under the GNU

General Public License.

Similar services are relatively common on the net,

but they are usually proprietary and also rather

unsatisfactory. PowerPhlogger allows everyone to set

up such a service, even if the relevant pages do not

support PHP. The creation of accounts with these

services can either be done by an administrator or the

users themselves. An example for this is the gratis

PowerPhlogger service, Freelogger.

The functionality of PowerPhlogger surpasses that

of most proprietary solutions. Among the features is

the counting of real visitor numbers through “unique

hits” instead of counting every page access. This is

done by IP-comparison in combination with a cookie-

check and a timeout defined by the user.

PowerPhlogger

In June 2000 Philip Iezzi began working on a

software to host Web page counters under PHP and

the result of his work has been available since

PowerPhlogger showing statistics

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filesystem hierarchy where other programs look for

them. If the package is to be uninstalled, one can

simply delete the install directory and/or remove the

links by calling Stow again.

Stow was originally written by Bob Glickstein in

1993 using Perl, but lack of time forced him to

suspend development. GNU Stow is now maintained

by Guillaume Morin, who has had only mainly minor

changes to implement since the project has been

stable for some years now.

If you haven’t tried out GNU Stow yet, I can only

recommend taking a look.

Process View Browser showing

diagrams and other widgets

PowerPhlogger also offers so-called “visitor paths”,

enabling administrators to trace the path a user has

taken to reach the page. It also keeps track of the

time a user spent browsing the page.

Of course the PowerPhlogger is capable of

displaying counters on pages that can be fitted to the

layout of the page through TTF and user-defined

colours. Even the layout of the statistics page can be

modified to suit the user’s taste with CSS

modifications. Additionally, the project has been

internationalised for 16 languages and supports

different time zones.

All data is currently stored in a mySQL database,

but version 3 of the PowerPhlogger, which is

pencilled in for an October 2002 release, will contain

a database abstraction layer. Also some of the less

desirable sections of code will be cleaned up and

rewritten for object orientation.

Help is welcome in any form, including financial

support. Philip also needs volunteers to provide

support in the online-forum.

GNU gettext

GNU gettext is a project probably known to most

developers already and also a package that only

developers and translators will ever come in direct

contact with. It does play a crucial role for users,

however, since it allows programs to communicate

with them in their native language. So I’d like to

introduce this important component here.

Although details should be spared, a short

introduction into the functional concept seems useful

at this point: when developing programs, all output is

normally written in English. All user interaction strings

are collected by GNU gettext in a single file.

If a program is to be localised, translators can make

a copy of this file, translate all the strings in this

simple ASCII file into their native language and mail it

back to the developer. If this file is then copied into

the right directory under the right name, the program

supports that language after the next compilation.

When the user runs the program, GNU gettext will

try to supply him or her with the messages in the

user’s preferred language. Whenever this isn’t

possible because the translation is not complete or

doesn’t exist at all, gettext falls back to the

original/English version.

Supporting incomplete translations was one of the

design goals of GNU gettext, because programs

evolve step by step and very often the translators are

one or two steps behind the developer.

GNU gettext consists of several tools under the

GNU General Public License as well as libraries under

the GNU Lesser General Public License. It complies

with the Unix-standards X/Open and Li18nux2000,

was originally written in 1995 by Ulrich Drepper. It

has since rapidly become the de-facto standard for

software internationalisation in and outside of the

GNU Project.

Bruno Haible recently took over as the GNU

gettext maintainer. He currently focuses on

expanding GNU gettext to more languages and is

considering integrating simple spell checking

sometime in the future.

Bruno felt two anecdotes were worth sharing with

the Brave GNU World audience. First of all there is a

distinguished and apparently quite active team

GNU Stow

GNU Stow is an extremely useful project for everyone

installing software that’s either not available for the

distribution you’re using or has to be installed from

source for other reasons.

Under normal circumstances such activities tend to

act as proof that the second law of thermodynamics

applies to computer systems, as well: entropy remains

the same or rises, but it never decreases. In other

words this means that systems have the tendency to

become increasingly messy. GNU Stow offers a

solution for this.

Stow has its own directory tree, which usually

resides at /usr/local/stow . New packages are installed

into their own subdirectories in this directory tree.

Calling Stow will create symbolic links, making sure

all files of the package appear in the standard

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working on the translations from American to British

English. This seemed somewhat easier than a

translation to Japanese to him.

He also warns other programmers against trying to

translate their programs in to another languages

themselves – especially if this is not their native

language. As far as he was concerned, some of the

translations he has encountered are worse than no

translation at all.

Experience shows that translations into French,

Swedish, German and Spanish are provided quite

often, other languages could use more volunteers,

however. Localising a program for your own language

is a very good way of furthering Free Software in a

practical way that needs little technical expertise.

Three years of Brave GNU World

What began as an experiment is now three years old,

so I’m tempted to take a quick glance back.

The column initially began as a wild idea between

Tom Schwaller and me on the 512-node GNU/Linux

Cluster “CLOWN”, at which I gave my first

appearance as European speaker for the GNU Project.

Tom approached me with the idea of a GNU

column. Arriving back home I knew that I wanted to

try writing a column that would also have the mix of

technical and philosophical issues making the GNU

Project so special. Still, I was sceptical whether this was

possible and whether I’d be able to fill the column

each and every month in time for the print-issue.

From the very first moment it was clear that the

column should also be published on the Net in order

to make it available to as many people as possible.

Doing this only in German seemed of limited use, so

the initial issue was first written in German and then

translated into English by me in order to be released

online together.

After releasing issue two, something remarkable

happened. Within a few days, Okuji Yoshinori and

Francois Thunus contacted me and asked whether I’d

agree to them translating the column into Japanese

and French. Of course I was quite happy about that

and immediately included them in the production

process of the Brave GNU World.

The dam broke; more volunteers contacted me for

other translations and soon other magazines

requested permission to print the Brave GNU World.

Today the column appears in up to 7 languages online

and 4 magazines worldwide. Without the help of so

many volunteers, this would never have been possible.

The companions of the early days mentioned above

all went their own ways by now, their jobs being taking

over by others. I’d like to list everyone helping with the

Brave GNU World, but there is hardly enough place for

it. On a single issue you’ll easily find 30 people helping

as scout, proofreader, translator, Web master and so

on. Even if some have participated for a long time now,

there is always a certain amount of fluctuation.

Pingus version 0.4.1

To all these people and the other supporters of the

Brave GNU World I would like to express my heartfelt

thanks to for the past three years. I’d also like to

thank all those who contacted me in person or via

email to tell me about interesting projects, give

feedback or discuss topics they had a different

opinion about. Their involvement was a seminal part

in filling the Brave GNU World with life.

...to another year

Enough said, I hope we’ll see another good year for

Brave GNU World and of course I don’t want to finish

without the mandatory request for feedback,

comments, new projects, questions and ideas. Which

project is incredibly useful, funny or good and still

unknown to many users? Please send answers to the

usual address.

Info

Send ideas, comments and

column@brave-gnu-world.org

questions to Brave GNU World

Homepage of the GNU Project

http://www.gnu.org

Homepage of Georg’s Brave

http://brave-gnu-world.org

GNU World

“We run GNU” initiative http://www.gnu.org/brave-gnu-world/

rungnu/ rungnu.en.html

Pingus homepage http://pingus.seul.org

XPenguins homepage http://xpenguins.seul.org

Process View Browser homepage http://pvbrowser.sourceforge.net

PowerPhlogger homepage

http://www.phpee.com

Freelogger homepage

http://www.freelogger.com

GNU Stow homepage

http://www.gnu.org/software/stow

GNU gettext homepage

http://www.gnu.org/software/gettext

“History and Philosophy

http://www.gnu.org/philosophy/greve-clown.en.html

of the GNU Project”

Issue 19 • 2002

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