Amit Deshpande and Dirk Riehle
SAP Research, SAP Labs LLC
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Introduction to Linux - LDP.org
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Some commands have multiple man pages. For instance, the passwd command has a man page in section 1 and another in section 5. By default, the man page with the lowest number is shown. If you want to see another section than the default, specify it after the man command:
man 5 passwd
If you want to see all man pages about a command, one after the other, use the -a to man:
man -a passwd
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In a file system, a file is represented by an inode, a kind of serial number containing information about the actual data that makes up the file: to whom this file belongs, and where is it located on the hard disk.
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iTWire - Be the next big thing in open source (Part 2)
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for maximum impact, cross platform tools and languages really are the best option
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Java is always available and for the most part its โwrite once, run everywhereโ mantra can be made to work. Python is also a popular stable.
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iTWire - Be the next big thing in open source
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Be the next big thing in open source
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Thereโs no sense putting fingers to keyboard until you know what you want to achieve. I have a belief that the best software is borne out of genuine need.
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Pimp your Amarok: 13 Scripts You Should Probably Know About | Royal HeHe2-ness!
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Pimp your Amarok: 13 Scripts You Should Know About
14Mar2008
Filed under: Linux:General
Author: Rami Taibah
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The Total Growth of Open Source
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The Total Growth of Open Source
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Abstract
Software development is undergoing a major change away from a fully closed software process towards a process that incorporates open source software in products and services. Just how significant is that change? To answer this question we need to look at the overall growth of open source as well as its growth rate. In this paper, we quantitatively analyze the growth of more than 5000 active and popular open source software projects. We show that the total amount of source code as well as the total number of open source projects is growing at an exponential rate. Previous research showed linear and quadratic growth in lines of source code of individual open source projects. Our work shows that open source is expanding into new domains and applications at an exponential rate.
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Matthias Ettrich: The KDE-Man!
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Matthias Ettrich: The KDE-Man!

Nobody in their right mind would choose Windows over GNU/Linux based on the desktop experience alone, says Matthias Ettrich. -
Where do you see KDE on Windows?
ME: When you say KDE, there're at least three of them: the development platform, the desktop and the set of applications built on top of that platform. You will always get the best KDE experience when using all three combined. - 1 more annotations...
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Linux.com :: Tuxcards and KnowIt: Open source outlining
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Another contains the complete history of my use of a particular computer -- all the software changes I've made, tips and tricks I discovered, and hardware issues.
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Linux Tip: Copy and paste without using the clipboard
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Linux users: In Gnome, you can paste text without previously copying it to the clipboard. How does this work? Glad you asked. First, highlight a chunk of text in any application, then open a new application and middle-click the mouse. The highlighted text will automatically get pasted into the active application -- bypassing the clipboard altogether! In fact, this method will not disturb the existing contents of the clipboard in any way. Talk about a time saver when copying text between applications -- like Firefox and the terminal.
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Santa~Li
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"How do I tweak Linux for broadband?"
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This document applies to kernel
2.4.x, and will also work on the 2.6.x kernel provided it is compiled with /proc file system support enabled - 6 more annotations...
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Salatti.NET ยป Tweak Ubuntu for speed
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Tweak Ubuntu for speed
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these tweaks will work with all forms of Linux
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- First we have to gain access to your /etc/sysctl.conf file.
- sudo gedit /etc/sysctl.conf
- Just scroll to the bottom of the page and add the tag listed below. The number you want depends on how much ram you have and what you do with your system. Please read the about above this to make your decision. I have mine set to 0 on a dual core laptop with 1 gig of ram and have seen no issues and a good performance gain.
- vm.swappiness=0
Swapping
About
Swappiness takes a value between 0 and 100 to change the balance between swapping applications and freeing cache. At 100, the kernel will always prefer to find inactive pages and swap them out; in other cases, whether a swapout occurs depends on how much application memory is in use and how poorly the cache is doing at finding and releasing inactive items.The default swappiness is 60. A value of 0 gives something close to the old behavior where applications that wanted memory could shrink the cache to a tiny fraction of RAM. For laptops which would prefer to let their disk spin down, a value of 20 or less is recommended.
Tweak
And youโre done.
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- You have to open your /etc/sysctl.conf file back up again.
- sudo gedit /etc/sysctl.conf
- Then again, scroll to the bottom and just add these lines to it.
- net.core.rmem_default = 524288
- net.core.rmem_max = 524288
- net.core.wmem_default = 524288
- net.core.wmem_max = 524288
- net.ipv4.tcp_wmem = 4096 87380 524288
- net.ipv4.tcp_rmem = 4096 87380 524288
- net.ipv4.tcp_mem = 524288 524288 524288
- net.ipv4.tcp_rfc1337 = 1
- net.ipv4.ip_no_pmtu_disc = 0
- net.ipv4.tcp_sack = 1
- net.ipv4.tcp_fack = 1
- net.ipv4.tcp_window_scaling = 1
- net.ipv4.tcp_timestamps = 1
- net.ipv4.tcp_ecn = 0
- net.ipv4.route.flush = 1
- You have to reset your sysctl for these to take effect.
- sudo sysctl -p
Broadband Internet
About
These are various tweaks taken from various places. Here is an article that explains them all if you would like to read it in depth.Tweak
And youโre done.
File security
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The permissions are always in the same order: read, write, execute for the user, the group and the others.
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Table 3-9. File protection with chmod
Command Meaning chmod 400 file To protect a file against accidental overwriting. chmod 500 directory To protect yourself from accidentally removing, renaming or moving files from this directory. chmod 600 file A private file only changeable by the user who entered this command. chmod 644 file A publicly readable file that can only be changed by the issuing user. chmod 660 file Users belonging to your group can change this file, others don't have any access to it at all. chmod 700 file Protects a file against any access from other users, while the issuing user still has full access. chmod 755 directory For files that should be readable and executable by others, but only changeable by the issuing user. chmod 775 file Standard file sharing mode for a group. chmod 777 file Everybody can do everything to this file. - 1 more annotations...
Orientation in the file system
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Table 3-3. Most common configuration files
File Information/service aliases
Mail aliases file for use with the Sendmail and Postfix mail server. Running a mail server on each and every system has long been common use in the UNIX world, and almost every Linux distribution still comes with a Sendmail package. In this file local user names are matched with real names as they occur in E-mail addresses, or with other local addresses.
apache
Config files for the Apache web server.
bashrc
The system-wide configuration file for the Bourne Again SHell. Defines functions and aliases for all users. Other shells may have their own system-wide config files, like cshrc.
crontab and the cron.* directories
Configuration of tasks that need to be executed periodically - backups, updates of the system databases, cleaning of the system, rotating logs etc.
default
Default options for certain commands, such as useradd.
filesystems
Known file systems: ext3, vfat, iso9660 etc.
fstab
Lists partitions and their mount points.
ftp*
Configuration of the ftp-server: who can connect, what parts of the system are accessible etc.
group
Configuration file for user groups. Use the shadow utilities groupadd, groupmod and groupdel to edit this file. Edit manually only if you really know what you are doing.
hosts
A list of machines that can be contacted using the network, but without the need for a domain name service. This has nothing to do with the system's network configuration, which is done in /etc/sysconfig.
inittab
Information for booting: mode, number of text consoles etc.
issue
Information about the distribution (release version and/or kernel info).
ld.so.conf
Locations of library files.
lilo.conf, silo.conf, aboot.conf etc.
Boot information for the LInux LOader, the system for booting that is now gradually being replaced with GRUB.
logrotate.*
Rotation of the logs, a system preventing the collection of huge amounts of log files.
mail
Directory containing instructions for the behavior of the mail server.
modules.confConfiguration of modules that enable special features (drivers).
motd
Message Of The Day: Shown to everyone who connects to the system (in text mode), may be used by the system admin to announce system services/maintenance etc.
mtab
Currently mounted file systems. It is advised to never edit this file.
nsswitch.conf
Order in which to contact the name resolvers when a process demands resolving of a host name.
pam.d
Configuration of authentication modules.
passwd
Lists local users. Use the shadow utilities useradd, usermod and userdel to edit this file. Edit manually only when you really know what you are doing.
printcap
Outdated but still frequently used printer configuration file. Don't edit this manually unless you really know what you are doing.
profile
System wide configuration of the shell environment: variables, default properties of new files, limitation of resources etc.
rc*
Directories defining active services for each run level.
resolv.conf
Order in which to contact DNS servers (Domain Name Servers only).
sendmail.cf
Main config file for the Sendmail server.
services
Connections accepted by this machine (open ports).
sndconfig or sound
Configuration of the sound card and sound events.
ssh
Directory containing the config files for secure shell client and server.
sysconfig
Directory containing the system configuration files: mouse, keyboard, network, desktop, system clock, power management etc. (specific to RedHat)
X11
Settings for the graphical server, X. RedHat uses XFree, which is reflected in the name of the main configuration file, XFree86Config. Also contains the general directions for the window managers available on the system, for example gdm, fvwm, twm, etc.
xinetd.* or inetd.conf
Configuration files for Internet services that are run from the system's (extended) Internet services daemon (servers that don't run an independent daemon).
General overview of the Linux file system
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Table 3-1. File types in a long list
Symbol Meaning - Regular file d Directory l Link c Special file s Socket p Named pipe b Block device -
1st possibility: one swap partition of 1 GB
2nd possibility: two swap partitions of 512 MB
3rd possibility: with two hard disks: 1 partition of 512 MB on each disk.
Linux generally counts on having twice the amount of physical memory in the form of swap space on the hard disk. When installing a system, you have to know how you are going to do this. An example on a system with 512 MB of RAM:
The last option will give the best results when a lot of I/O is to be expected.
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