LQWiki - User contributions [en]

Qotd

2006-02-04T01:50:13Z

Dysprosia: qotd is also the name for a basic networking service that displays a qotd on connect, on port 17.

'''qotd''' is an acronym for "quote of the day"

Some systems are set up to display the qotd on the [[console]] right after a user [[authenticate]]s him/herself to the system.

qotd is also the name for a basic networking service that displays a qotd on connect, on port 17.

==See also==
*[[motd|Message of the Day]]

Lex

2005-09-15T12:01:11Z

Dysprosia: tt it

'''lex''' is a program which generates code in the C programming language to create a lexical analyser - that is, a program which creates a program that can perform certain tasks based on matching input.

The program makes use of [[regular expression]]s to identify certain elements of the input known as ''tokens''. Different code fragments can be assigned to be executed once a certain token is encountered in the input.

<tt>lex</tt> is often used with <tt>[[yacc]]</tt>/<tt>[[bison]]</tt>, but they have different purposes.

<tt>[[flex]]</tt> is an open source implementation of lex.

''This article is a [[LQWiki:stub_articles|stub]] and needs to be finished. [[LQWiki:plunging_forward|Plunge forward]] and [[LQWiki:How_to_edit_a_page|help it grow]] !''

Lex

2005-09-15T11:58:25Z

Dysprosia: various bits and pieces here and there

'''lex''' is a program which generates code in the C programming language to create a lexical analyser - that is, a program which creates a program that can perform certain tasks based on matching input.

The program makes use of [[regular expression]]s to identify certain elements of the input known as ''tokens''. Different code fragments can be assigned to be executed once a certain token is encountered in the input.

<tt>lex</tt> is often used with <tt>[[yacc]]</tt>/<tt>[[bison]]</tt>, but they have different purposes.

[[flex]] is an open source implementation of lex.

''This article is a [[LQWiki:stub_articles|stub]] and needs to be finished. [[LQWiki:plunging_forward|Plunge forward]] and [[LQWiki:How_to_edit_a_page|help it grow]] !''

Du

2005-09-15T11:54:41Z

Dysprosia: put mnemonic device back

'''du''' ('''d'''isk '''u'''sage) is a tool which displays how the disk is used. It can be used to determine the sizes of files or directories without resorting to <tt>[[ls]]</tt>.

==Example use==

To determine the size of the current directory
$ du -sh

The -s flag is used to get a summary of the disk usage (the total size) in the current directory, -h lists amounts in human-readable terms of "K" for kilobytes, "M" for megabytes and "G" for gigabytes, instead of numbers of blocks.

To determine the sizes of each file in the current directory,
$ du -sh *
lists each file with its size. In Linux, the <tt>--max-depth=1</tt> can be used to similar effect.

If you want to know the largest ten files in the current directory, one can use:
$ du -s * | sort -nr | head
to list these files.

==See also==
*[[Causes of Filesystem Usage Discrepancies]]

Df

2005-09-15T11:54:30Z

Dysprosia: eww. clean.

'''df''' displays free disk space on each [[mount]]ed volume. The tool displays the file system, total size, amount used and available, this information as a percentage, and the mount point.

Using the <tt>-h</tt> flag lists amounts in human-readable terms of "K" for kilobytes, "M" for megabytes and "G" for gigabytes, instead of numbers of blocks.

== Example ==
$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/hda2 74G 34G 41G 46% /
/dev/hdc1 150G 44G 106G 29% /bulk
shmfs 94M 0 94M 0% /dev/shm

Du

2005-09-15T11:51:11Z

Dysprosia: clean up

'''du''' ('''d'''isk '''u'''sage) is a tool which displays how the disk is used. It can be used to determine the sizes of files or directories without resorting to <tt>[[ls]]</tt>.

==Example use==

To determine the size of the current directory
$ du -sh

The -s flag is used to get a summary of the disk usage (the total size) in the current directory, -h lists amounts in terms of "K" for kilobytes, "M" for megabytes and "G" for gigabytes, instead of numbers of blocks.

To determine the sizes of each file in the current directory,
$ du -sh *
lists each file with its size. In Linux, the <tt>--max-depth=1</tt> can be used to similar effect.

If you want to know the largest ten files in the current directory, one can use:
$ du -s * | sort -nr | head
to list these files.

==See also==
*[[Causes of Filesystem Usage Discrepancies]]

Recover a terminal session

2005-06-01T23:55:35Z

Dysprosia: enough bash-dependency

If your [[terminal]] is covered in garbage, and/or not responding, here are a few things you can do:

* If none of the keys appear to work, "[[echo]]" may have been turned off. You can clear this sort of problem by carefully typing:

:<tt>^Jstty sane^J</tt> (where <tt>^J</tt> means hold the <tt>Ctrl</tt> key while tapping the <tt>J</tt> key).

* If upper-case letters display properly but lower-case are displayed as graphics characters, you can turn the graphics off with this command:

: <tt>echo -e "\017"</tt>
or
: <tt>echo ^V^O</tt>
where one types Control-V and then Control-O*.
*Note that Control-V allows a normally nonprinting control character to be entered without the control character taking effect. For example, entering ^V^C into an editor will not quit the editor but allow you to insert the control character instead

* If you can type things but want to clear the screen, press <tt>^L</tt> or run the "<tt>clear</tt>" command.

* If your terminal settings are still not correct, try running the "<tt>reset</tt>" command.

* You can also try <tt>echo -e "\\033c";tput is2;stty sane line 1</tt>

Talk:Tar

2005-05-11T11:34:49Z

Dysprosia: reply

why would you use tar to copy files?
: <tt>cp -r</tt> is broken on older systems - using tar is thus portable. [[User:Dysprosia|Dysprosia]] 19:14, Aug 30, 2004 (EDT)

Is it only possible to extract all files, or can single files be extracted?

: I don't know how good the Linux man pages are, but <tt>man tar</tt> on my 'BSD machine says: "-x Extract files from archive. If any files are named on the command line, only those files will be extracted from the archive." [[User:Dysprosia|Dysprosia]] 07:34, May 11, 2005 (EDT)

Malloc

2005-05-10T23:32:25Z

Dysprosia: unmanpageify

The '''<tt>malloc</tt>''' utilities in the C standard library are used to achieve dynamic memory allocation. Normally, in C, memory is created and released with the stack -- that is, a fixed block of memory can be allocated when one enters a function, but is released and must be released when the function returns. This form of memory management however is somewhat inflexible, and dynamic memory allocation with utilities such as malloc alleviate this necessity.

The <tt>malloc</tt> function is used to return a [[pointer]] to the block of memory dynamically allocated. It takes one argument -- the size of the block of memory in bytes to allocate. It returns a <tt>void *</tt>, that is, a raw pointer to memory, and must be cast to the correct type of pointer when used. Since one includes the stdlib.h header when one wishes to use malloc, the cast is done automatically.

For an example of typical usage, consider the following example

#include <stdio.h>
#include <string.h>

int
main(void)
{
char str[20];

strcpy(str, "Hello!");
printf("%s\n", str);

return 0;
}

can equivalently be written
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int
main(void)
{
char *str = malloc(sizeof(char)*20);

strcpy(str, "Hello!");
printf("%s\n", str);

return 0;
}

Note that some data type may not take up one byte exactly, so it is a common idiom to give the size argument to <tt>malloc</tt> in terms of <tt>sizeof(type)*no_of_type</tt>.

If malloc fails to allocate memory, it will return NULL.

There are other dynamic memory allocation functions available, such as
* [[realloc]], which can grow or shrink a chunk of memory as needed
* calloc, which can zero a chunk of memory (or, one can use malloc and memset in tandem)

Malloc

2005-05-10T23:32:05Z

Dysprosia: unmanpageify

The '''<tt>malloc</tt>''' utilities in the C standard library are used to achieve dynamic memory allocation. Normally, in C, memory is created and released with the stack -- that is, a fixed block of memory can be allocated when one enters a function, but is released and must be released when the function returns. This form of memory management however is somewhat inflexible, and dynamic memory allocation with utilities such as malloc alleviate this necessity.

The <tt>malloc</tt> function is used to return a [[pointer]] to the block of memory dynamically allocated. It takes one argument -- the size of the block of memory in bytes to allocate. It returns a <tt>void *</tt>, that is, a raw pointer to memory, and must be cast to the correct type of pointer when used. Since one includes the stdlib.h header when one wishes to use malloc, the cast is done automatically.

For an example of typical usage, consider the following example

#include <stdio.h>
#include <string.h>

int
main(void)
{
char str[20];

strcpy(str, "Hello!");
printf("%s\n", str);

return 0;
}

can equivalently be written
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int
main(void)
{
char *str = malloc(sizeof(char)*20);

strcpy(str, "Hello!");
printf("%s\n", str);

return 0;
}

Note that some data type may not take up one byte exactly, so it is a common idiom to give the size argument to <tt>malloc</tt> in terms of <tt>sizeof(type)*no_of_type</tt>.

If malloc fails to allocate memory, it will return NULL.

There are other dynamic memory allocation functions available, such as
* realloc, which can grow or shrink a chunk of memory as needed
* calloc, which can zero a chunk of memory (or, one can use malloc and memset in tandem)

Chkconfig

2005-05-10T23:19:25Z

Dysprosia: if i wanted the manual i'd man chkconfig, as would any other user

<tt>'''chkconfig'''</tt> is a [[Linux]] tool to view and modify information about runlevel configuration files, viz., maintaining the /etc/rc[0-6].d directory hierarchy by relieving system administrators of the task of directly manipulating the numerous symbolic links in those directories.

The Linux version directly manages the symlinks in /etc/rc[0-6].d. This leaves all of the configuration information regarding what services [[init]] starts in a single location. <tt>chkconfig</tt> has five distinct functions: adding new services for management, removing services from management, listing the current startup information for services, changing the startup information for services, and checking the startup state of a particular service. When chkconfig is run without any options, it displays usage information.

{{stub}}

BeOS

2005-05-10T23:14:14Z

Dysprosia: clean up and clarify

BeOS was an operating system developed by Be, Inc in the early 1990's. It was ahead of its time in many areas, and some of its more futuristic attributes (i.e. detailed file metadata, 64-bit filesystem) are only now starting to show up in mainstream operating systems. Unfortunately, it never attracted enough consumer interest to remain a viable commercial product.
A free version known as BeOS Personal Edition, which can be started from within Windows and Linux is still available, and a dedicated community continues to release patches, software and and driver updates.

BeOS features a POSIX compatibility layer, but is not based on Unix.

== External links ==
* http://www.BeBits.com.

Programming in X

2005-04-01T04:59:18Z

Dysprosia: ++

Programming in X, due to having several facets and aspects in its operation, can be complex.

== Concepts ==
Some basic X concepts include:
*The [[X Window System]] behaves by acting as a "server" for X-enabled applications, called "clients".
*X is a network based system - clients can "draw" on another X server across a network.

== Libraries ==
The [[X Window System]] is known for providing basic window drawing and graphics management routines, however, X on its own provides no capabilities to draw typical utilities such as scrollbars. Libraries however exist that make use of the basic facilities that X provides to create extra graphical functionality.

* [[GNOME]], http://www.gnome.org/ - GNOME is a desktop environment for Linux, Unix, and other compatiable operating systems. It uses the GTK+ Toolkit and a [[Window Manager]] called Metacity.
** [[GTK|gtk+]], http://www.gtk.org/ - The GIMP Toolkit. GTK+ is a multi-platform toolkit for creating graphical user interfaces.
* [[KDE]], http://www.kde.org/ - Another [[Window Manager]] that provides a toolkit but this one is based on qt.
** [[Qt]], http://www.trolltech.com/ - A cross platform c++ GUI/API. Free for open source use but to develop commercial applications you need a license
* Motif, http://www.opengroup.org/motif/
* wxWidgets, http://www.wxwindows.org/ - An open source c++ GUI framework.
* XLib provides a C based interface to the basic graphic routines described above.

=== Qt ===
Qt is unique in that it uses the idea of signals and slots. What does this mean? Say you create a button [[widget]] to quit you program called "close_btn" you would then connect that signal to close().

connect(quit_btn, SIGNAL(clicked()),
this, SLOT(close()) );

The above code creates a connection between the button "quit_btn" and the close() slot. Specifically, when the quit_btn emits a clicked() signal the program does the slot close().

There is more to qt than just signals and slots and if you want to find more information, there is a good book called "C++ GUI Programming with Qt3" by Jasmin Blanchette and Mark Summerfield which is part of Bruce Perens' Open Source Series. There are also a number of tutorials on trolltech's, the maker of Qt, site: http://www.trolltech.com/.

=== XLib ===
* http://www.ac3.edu.au/SGI_Developer/books/XLib_PG/sgi_html/, Information on the X standard
* http://www.ac3.edu.au/SGI_Developer/books/XLib_PG/sgi_html/ix01.html, more specific information

Programming in X

2005-04-01T04:57:01Z

Dysprosia: triedto clean up, needs more

Programming in X, due to having several facets and aspects in its operation, can be complex.

== Concepts ==
Some basic X concepts include:
*The [[X Window System]] behaves by acting as a "server" for X-enabled applications, called "clients".
*X is a network based system - clients can "draw" on another X server across a network.

== Libraries ==
The [[X Window System]] is known for providing basic window drawing and graphics management routines, however, X on its own provides no capabilities to draw typical utilities such as scrollbars. Libraries however exist that make use of the basic facilities that X provides to create extra graphical functionality.

* [[GNOME]], http://www.gnome.org/ - GNOME is a desktop environment for Linux, Unix, and other compatiable operating systems. It uses the GTK+ Toolkit and a [[Window Manager]] called Metacity.
** [[GTK|gtk+]], http://www.gtk.org/ - The GIMP Toolkit. GTK+ is a multi-platform toolkit for creating graphical user interfaces.
* [[KDE]], http://www.kde.org/ - Another [[Window Manager]] that provides a toolkit but this one is based on qt.
** [[Qt]], http://www.trolltech.com/ - A cross platform c++ GUI/API. Free for open source use but to develop commercial applications you need a license
* Motif, http://www.opengroup.org/motif/
* wxWidgets, http://www.wxwindows.org/ - An open source c++ GUI framework.
* XLib provides a C based interface to the basic graphic routines described above.

=== Qt ===
Qt is unique in that it uses the idea of signals and slots. What does this mean? Say you create a button [[widget]] to quit you program called "close_btn" you would then connect that signal to close().

connect(quit_btn, SIGNAL(clicked()),
this, SLOT(close()) );

The above code creates a connection between the button "quit_btn" and the close() slot. Specifically, when the quit_btn emits a clicked() signal the program does the slot close().

There is more to qt than just signals and slots and if you want to find more information, there is a good book called "C++ GUI Programming with Qt3" by Jasmin Blanchette and Mark Summerfield which is part of Bruce Perens' Open Source Series. There are also a number of tutorials on trolltech's, the maker of Qt, site: http://www.trolltech.com/.

== XLib ==
* http://www.ac3.edu.au/SGI_Developer/books/XLib_PG/sgi_html/, Information on the X standard
* http://www.ac3.edu.au/SGI_Developer/books/XLib_PG/sgi_html/ix01.html, more specific information

Bc

2005-02-21T14:56:12Z

Dysprosia: == See also == * dc

'''bc''' is a language that supports arbitrary precision numbers with interactive execution of statements. There are some similarities in the syntax to the [[C]] programming language. A standard math [[library]] is available by [[command line]] option. If requested, the math library is defined before processing any files. bc starts by processing code from all the files listed on the command line in the order listed. After all files have been processed, bc reads from the [[standard input]]. All code is executed as it is read. (If a file contains a command to halt the processor, bc will never read from the standard input.)

== See also ==
* [[dc]]

Talk:Bc

2005-02-21T14:54:38Z

Dysprosia: : Regardless of copyrights, man pages are absolutely unsuitable. ~~~~

Looks like a rip from the man page. How are we on the copyrights? [[User:Crazyeddie|Crazyeddie]] 21:15, Feb 17, 2005 (EST)
: Regardless of copyrights, man pages are absolutely unsuitable. [[User:Dysprosia|Dysprosia]] 09:54, Feb 21, 2005 (EST)

Objdump

2005-02-04T05:32:15Z

Dysprosia: clean up

'''<tt>objdump</tt>''' is a tool to work with [[binary]] [[object file]]s. It is part of the [[GNU]] [[binutils]].

<tt>objdump</tt> can be used for disassembly, with the <tt>-d</tt> flag, eg.
objdump -d executable

If the executable has been compiled with debugging information, the <tt>-S</tt> flag will intermix source and disassembled code.

The <tt>--syms</tt> flag shows symbol information.

Nohup

2005-02-04T05:26:46Z

Dysprosia: clean up. don't describe shell details in the article

'''<tt>nohup</tt>''' is a command used to run a [[process]] and have it continue to run regardless whether you log out and close the connection to a server.

When you are connected to a server and wish to log out, a hangup ([[SIGHUP]]) signal is sent to all the processes you have run. Using <tt>nohup</tt> to run a program causes this signal to be ignored.

For example, you might want to download some files with <tt>[[wget]]</tt>, and be able to log out and have these files still download for you. One could use
nohup wget --quiet http://www.example.com/some_large_file &
to have wget download these files in the [[background]], and continue to do so even after you log out. The quiet flag is set because while wget is in the background, the job will suspend if it creates any output to the terminal.

The use of <tt>nohup</tt> is not restricted to remote logins, however, one can use it for example in [[X]], with an <tt>[[xterm]]</tt> open, one can nohup a process and have it run even if the xterm is closed.

{{stub}}

Nohup

2005-02-04T05:17:34Z

Dysprosia: don't sign articles, first of all

'''Nohup''' is a command used to allow processes to execute while ignoring any hangup requests.

For example, you may have an executable file you compiled as <tt>my_executable</tt>. If you want this executable to run even if you log out of the computer (or receive any other hangup request), you can do so with the following command.

nohup my_executable

You can also add an ampersand (&) at the end of the previous command to assign the process to the background. If <tt>my_exectuable</tt> sends data to the standard output, you can redirect this output to a file called <tt>my_output</tt>.

nohup my_executable > my_output &

Sometimes the executable in question requires a <tt>./</tt> to specifically denote your desire to execute the given command.

nohup ./my_executable > my_output &

You can always check to see if your process is still running with the [[ps]] command.

{{stub}}

Ed

2005-01-16T13:23:42Z

Dysprosia: unpre. pre is bad

'''ed''' is one of the most noted original editors on Unix and Unix-like systems written by Ken Thompson. Ed is a line editor unlike the newer screen oriented editors [[vi]] or [[emacs]].

It is noted for its extreme terseness, and has been the subject to Usenet humor, such as the post below.

It is the default command-line based editor in the [[Plan 9]] [[operating system]], apart from [[acme]] and [[sam]].

==To use ed==
$ed

a ''(To add or append text)''
Type something here.
. ''(Signals end of input. Will not show up in file)''
w foo ''(Write to file named foo)''
q ''(To quit ed)''
$ cat foo
Type something here.
$

It is important to remember that ed is a line editing tool. This means that it deals with the text of a file one line at a time or as groups of lines. When this is understood the basic usage of ed becomes fairly simple. The file is loaded into a buffer which is independent from the copy on the disk until you write it out. ed is also a modal editor. This means it has separate command and input modes much like [[vi]].

===Basic Commands===

a -- append a new line after the current line.
i -- insert a new line above the current line.
d -- delete the current line.
p -- print the current line.
n -- print the current line preceded by it's line number.
u -- undo the last command (a second u undoes the undo).
w -- write the buffer to disk.
q -- quit.

h -- expand on last error ?.

Note on the '?' for an error. If you want to know what the error dealt with you can enter the command 'h' and it will give you a "slightly" better error message.

===Usage===

If you refer to the first example given you see a clear guide of usage. When you first enter ed you are in command mode. If you have loaded a pre-existing file, ed will print the number of bytes loaded and wait for your command. It automatically starts you with your current line equal to the last line of the file so you can easily start appending text.

Almost all of ed's commands can take a line number or a range of lines as an option. For example, to print the first 10 lines of a file you would enter:
1,10p

To delete the 5th line from a file all you need to do is enter:
5d

Movement is also very easy. You just enter the line number you wish to go to. To get the the start of a file after you load it, simple enter:
1

There are some other little shortcuts to know about when dealing with lines. A '$' (dollar sign) refers to the last line of the file. A '.' (period) refers to the current line. This is very useful because you can use these before any command to give a range for it to work on. To delete every line from the current line to the end of the file, you would enter:
.,$d

What happens frequently is you will enter a command and not see your expected result. There is no error (?) just complete silence. In almost every instance of this you are in input mode and not command mode. To exit input mode you need to enter a '.' on a line by itself. What follows is an example editing session. The comments (everything after the ;) are not supposed to be typed in.

$ed
5432 ''; The number of bytes loaded.''
. ''; This prints the current line.''
What a funny line to end a file with.
.= ''; Print the current line number.''
132
130,$p ''; Print the last three lines.''
This is weird.
A fake little file.
What a funny line to end a file with.
d ''; delete the current line''
a ''; add new text.''
This is a much better final line.
p
''; ??? Why didn't this show our new line?''
''; Because we are still in input mode.''
. ''; exit input mode''
p ''; print the current line''
p ''; it is our 'p' we accidentally added''
d ''; delete the current line''
p ''; print our new current line''
This is a much better final line.
w ''; that is good so save the file''
5428 ''; the number of bytes saved''
q ''; quit''

Knowing these simple commands and understanding how they effect the file can often save you if you are unable to use a different editor. ed is actually a very nice little editor with some built in power which might surprise you. The man page is highly recommended reading and it never hurt anyone to spend 15-20 minutes experimenting with this editor. [http://www.freebsd.org/cgi/man.cgi?query=ed&apropos=0&sektion=0&manpath=Red+Hat+Linux%2Fi386+9&format=html ed man page]

==Jargon File on ed==
“ed is the standard text editor.” Line taken from the original Unix manual page on ed, an ancient line-oriented editor that is by now used only by a few [[Real Programmer]]s, and even then only for [[batch]] operations. The original line is sometimes uttered near the beginning of an [[emacs]] vs. [[vi]] [[holy war]] on [[Usenet]], with the (vain) hope to quench the discussion before it really takes off. Often followed by a standard text describing the many virtues of ed (such as the small memory footprint on a Timex Sinclair, and the consistent (because nearly non-existent) user interface).

(from the [[Jargon File]])

== Usenet humor about ed==



----- Begin included message -----
From: patl@athena.mit.edu (Patrick J. LoPresti)
Message-ID: <1991Jul11.031731.9260@athena.mit.edu>
Sender: news@athena.mit.edu (News system)
Subject: The True Path (long)
Date: 11 Jul 91 03:17:31 GMT
Newsgroups: alt.religion.emacs,alt.slack
Organization: Massachusetts Institute of Technology
Lines: 95

When I log into my [[Xenix]] system with my 110 baud [[teletype]], both [[vi]]
*and* [[Emacs]] are just too damn slow. They print useless messages like,
'C-h for help' and '"[[foo]]" File is read only'. So I use the editor
that doesn't waste my VALUABLE time.

Ed, man! ![[man]] ed

ED(1) UNIX Programmer's Manual ED(1)

NAME
ed - text editor

SYNOPSIS
ed [ - ] [ -x ] [ name ]
DESCRIPTION
Ed is the standard text editor.
-----

Computer Scientists love ed, not just because it comes first
alphabetically, but because it's the standard. Everyone else loves ed
because it's ED!

"Ed is the standard text editor."

And ed doesn't waste space on my Timex Sinclair. Just look:

-rwxr-xr-x 1 root 24 Oct 29 1929 /bin/ed
-rwxr-xr-t 4 root 1310720 Jan 1 1970 /usr/ucb/vi
-rwxr-xr-x 1 root 5.89824e37 Oct 22 1990 /usr/bin/emacs

Of course, on the system *I* administrate, vi is symlinked to ed.
Emacs has been replaced by a shell script which 1) Generates a syslog
message at level LOG_EMERG; 2) reduces the user's disk quota by 100K;
and 3) RUNS ED!!!!!!

"Ed is the standard text editor."

Let's look at a typical novice's session with the mighty ed:

golem> ed

?
help
?
?
?
quit
?
exit
?
bye
?
hello?
?
[[eat flaming death]]
?
^C
?
^C
?
^D
?

---
Note the consistent user interface and error reportage. Ed is
generous enough to flag errors, yet prudent enough not to overwhelm
the novice with verbosity.

"Ed is the standard text editor."

Ed, the greatest [[WYGIWYG]] editor of all.

ED IS THE TRUE PATH TO NIRVANA! ED HAS BEEN THE CHOICE OF
EDUCATED AND IGNORANT ALIKE FOR CENTURIES! ED WILL NOT CORRUPT YOUR
PRECIOUS BODILY FLUIDS!! ED IS THE STANDARD TEXT EDITOR! ED MAKES THE SUN
SHINE AND THE BIRDS SING AND THE GRASS GREEN!!

When I use an editor, I don't want eight extra KILOBYTES of worthless
help screens and cursor positioning code! I just want an EDitor!!
Not a "viitor". Not a "emacsitor". Those aren't even WORDS!!!! ED!
ED! ED IS THE STANDARD!!!

TEXT EDITOR.

When IBM, in its ever-present omnipotence, needed to base their
"edlin" on a UNIX standard, did they mimic vi? No. Emacs? Surely
you jest. They chose the most karmic editor of all. The standard.

Ed is for those who can *remember* what they are working on. If you
are an idiot, you should use Emacs. If you are an Emacs, you should
not be vi. If you use ED, you are on THE PATH TO REDEMPTION. THE
SO-CALLED "VISUAL" EDITORS HAVE BEEN PLACED HERE BY ED TO
TEMPT THE FAITHLESS. DO NOT GIVE IN!!! THE MIGHTY ED HAS SPOKEN!!!

--
Miquel van Smoorenburg | Our vision is to speed up time,
miquels@cistron.nl | eventually eliminating it.

----- End included message -----

Whoami

2004-12-17T09:06:30Z

Dysprosia: rewrite

The [[command]] '''whoami''' simply outputs the username of the currently logged in user. If your username is "foo", then, for example:
$ whoami
foo
$

This command is useful to remind you of which user you are, say, if you are connecting to several machines, or you are using [[su]] to substitute a different user than your own, or in other circumstances. For this reason, most shell prompts have the capability of placing the username in the prompt (as well as the [[hostname]]), for example
foo@somehost $

The command can also be useful for scripting purposes.

User-Mode Linux

2004-12-13T10:48:11Z

Dysprosia: clean up

'''User-Mode Linux''' (UML) is a specially compiled Linux [[kernel]] which runs on another Linux kernel system. It enables you to test software, kernels and [[distribution]]s, without affecting your current system. The kernel can be assigned virtual resources, including a root filesystem and swap space, and can have a hardware configuration entirely separated from that of the host.

User-Mode Linux has become a part of the mainstream 2.6 Linux kernel and allows you to run Linux on top of Linux. This tool could be very useful when learning Linux as it allows new users to potentially destroy their Linux installation and replace it quickly with a fresh one, after taking a backup.

Often, operating systems make a distinction between the kernel and the programs that the kernel manages, creating two seperate "spaces", user-mode and kernel-mode. The system is termed "user-mode" because the system is running as another user program, and is seperate from the actual kernel space.

==See also==
*[[Emulators and virtual machines]]

==External links==
*[http://www.usermodelinux.org/ usermodelinux.org]
*[http://user-mode-linux.sourceforge.net Project on Sourceforge]

===UML hosting providers===
*[http://www.usermodelinux.de/ usermodelinux.de]
*[http://www.bytemark.co.uk/ bytemark.co.uk]
*[http://www.linode.com/ linode.com]

----
''This article is a [[LQWiki:stub_articles|stub]] and needs to be finished. [[LQWiki:plunging_forward|Plunge forward]] and [[LQWiki:How_to_edit_a_page|help it grow]] !''

User-Mode Linux

2004-12-13T10:48:01Z

Dysprosia: clean up

'''User-Mode Linux''' (UML) is a specially compiled Linux [[kernel]] which runs on another Linux kernel system. It enables you to test software, kernels and [[distribution]]s, without affecting your current system. The kernel can be assigned virtual resources, including a root filesystem and swap space, and can have a hardware configuration entirely separated from that of the host.

User-Mode Linux has become a part of the mainstream 2.6 Linux kernel and allows you to run Linux on top of Linux. This tool could be very useful when learning Linux as it allows new users to potentially destroy their Linux installation and replace it quickly with a fresh one, after taking a backup.

Often, operating systems make a distinction between the kernel and the programs that the kernel manages, creating two seperate "spaces", user-mode and kernel-mode. The system is termed "user-mode" because the system is running as another user program, and is seperate from the actual kernel space.

==See also==
*[[Emulators and virtual machines]]

==External links==
*[http://www.usermodelinux.org/ usermodelinux.org]
*[http://user-mode-linux.sourceforge.net Project on Sourceforge]

==UML hosting providers==
*[http://www.usermodelinux.de/ usermodelinux.de]
*[http://www.bytemark.co.uk/ bytemark.co.uk]
*[http://www.linode.com/ linode.com]

----
''This article is a [[LQWiki:stub_articles|stub]] and needs to be finished. [[LQWiki:plunging_forward|Plunge forward]] and [[LQWiki:How_to_edit_a_page|help it grow]] !''

Talk:Mount - What to do when umount doesn't work

2004-12-13T10:44:12Z

Dysprosia: This pagename is horrible. It needs to be moved somewhere. I'll do this tomorrow if need be. ~~~~

This pagename is horrible. It needs to be moved somewhere. I'll do this tomorrow if need be. [[User:Dysprosia|Dysprosia]] 05:44, Dec 13, 2004 (EST)

Mount

2004-12-03T11:57:57Z

Dysprosia: tidy up a bit, this needs some work still...

'''Mount''' refers to both an action and a command. Linux and other Unix-like operating systems deal with disks and file systems in a different manner than some operating systems such as Linux. Instead of assigning a drive letter to each drive, operating systems such as Linux instead deal with a single hierachy, known as a unified [[filesystem]]. A drive (represented by a [[device]], listed under <tt>/dev</tt>) is ''mounted'', and the files on the drive are made accessible as a directory under this single hierachy. The <tt>mount</tt> tool is used to mount a device.

Linux and other Unix-based operating systems, however, can deal with disks and devices in multiple formats. Consider trying to mount a [[CD-ROM]]. We need to know the following information:
* the [[device name]],
* the format
* where you want the files to appear ([[mount point]]).

For example, [[CD-ROM]] disks use the [[ISO9660]] format, and the device name is <tt>/dev/cdrom</tt>. There is a directory available for mounting [[CD-ROM]] disks, and that is <tt>/mnt/cdrom</tt>, so we might use this command to mount a CD-ROM disk:
mount -t iso9660 /dev/cdrom /mnt/cdrom

In general, you can call mount directly from the [[command line]], using the following general [[syntax]]:
mount [options] [device] [dir]

During the installation process, most linux [[distribution]]s create a file called [[fstab|/etc/fstab]], the [[filesystem]] table. This file contains mount settings for the [[volume]]s installed in your system. This means that we can avoid having to type in the [[device name]], format, etcetera, if we merely want to mount a CD. For example, if line did not exist already, you could add the following line in your [[fstab|/etc/fstab]] file for your cdrom drive (the first line here is just a helper for you; only add the /dev/cdrom line to [[fstab|/etc/fstab]]):
(device name) (mount point) (filesystem types) (options) (usually 0 0)
/dev/cdrom /cdrom iso9660 ro,user,noauto 0 0

Then, when you want to mount a new CD, you would just type <tt>mount /cdrom</tt>.

By default, many linux distributions will require you to [[go root]] to mount and [[umount|unmount]] volumes (this is signified by the lack of an option "user" or "users" on the line). Example of a root-only-mountable device:

/dev/floppy /mnt/floppy auto noauto,defaults 0 0

To change [[fstab|/etc/fstab]] so that any user can mount (and unmount) his or her own devices, make sure there's an option "user" in the list of options (the fourth thing on the line between filesystem type and the two 0's at the end of the line) for that device {the "user" option is so user mike can mount his cdrom and then only he can [[umount|unmount]] it}.

To make it so that any user can mount any device or [[umount|unmount]] any device, add the options "users" to the list of options for that device {the "users" option is so that mike can mount the cdrom but he or any other regular user can unmount it at any time}. Examples:

/dev/floppy1 /mnt/floppy1 auto noauto,defaults,user 0 0

/dev/floppy2 /mnt/floppy2 auto noauto,defaults,users 0 0

For more information on the mount command, type man mount at any shell prompt.

== Mounting an ISO image from an ordinary file ==

Sometimes it is useful to mount an [[ISO image]] file that you made or have downloaded to be able to access or check the contents. In Linux, this is known as ''loopback mounting'' and is done by using the loopback device.
This is possible with the following command:

mount -t iso9660 -o ro,loop=/dev/loop0 NameOfISOFile MountPoint

Other Unix-like systems may provide other means.

== See Also ==

* [[umount]]
* [[fstab|/etc/fstab]]
* [[Making an ISO from CDROM]]

LQWiki:Sandbox

2004-12-03T11:55:22Z

Dysprosia: {{sandbox}}

{{sandbox}} 
Kaffiene

http://images.freshmeat.net/screenshots/42710_thumb.png

<math> \sum_{n=0}^\infty \frac{x^n}{n!} </math>

Template:Sandbox

2004-12-03T11:54:56Z

Dysprosia: +hr

{| border=1
|
This page is called the '''Sandbox''', and it is simply a page for trying out/testing your Wiki markup. (For more information on Wiki markup itself, see the [[LQWiki:Wiki markup|Wiki markup guide]]). To use this page, simply click on the '''Edit tab''' link above - then - type in the markup/content that you want to test out, then click on the '''Show preview''' button below the edit box to see what the markup produces.
|}
----

Template:Sandbox

2004-12-03T11:54:28Z

Dysprosia: use preexisting sandbox message

Talk:LinuxQuestions.org Wiki:Sandbox

2004-12-03T11:53:19Z

Dysprosia: #REDIRECT LQWiki talk:Sandbox

#REDIRECT [[LQWiki talk:Sandbox]]

LinuxQuestions.org Wiki:Sandbox

2004-12-03T11:52:51Z

Dysprosia: #REDIRECT LQWiki:Sandbox

#REDIRECT [[LQWiki:Sandbox]]

LinuxQuestions.org Wiki:Sandbox

2004-12-02T10:48:39Z

Dysprosia: {{sandbox}}

{{sandbox}}

Ddd

2004-12-02T10:48:02Z

Dysprosia: tidy

'''ddd''' ('''D'''ata '''D'''isplay '''D'''ebugger) is a graphical wrapper for [[gdb]] and other [[debuggers]], using [[motif]]. It can be much easier to use than most regular debuggers as you don't need to be familiar with the commands or tools needed to operate them.

It provides other features that can be advantageous over using the command line interface for the debuggers, such as visualization of data structures, and point-and-click setting of breakpoints or watches.

==External links==
*[http://www.gnu.org/software/ddd/ ddd Homepage]

Gdb

2004-12-02T10:46:04Z

Dysprosia: tidy up

'''gdb''' ([[GNU]] Debugger) is a software [[debugger]]. It can be used to diagnose software runtime errors, such as segmentation faults, or other errors that are not easily detectable or diagnosable at runtime. It can perform typical debugger functions such as breakpoints, watching, stepping, and so on.

As with most [[Unix_philosophy|UNIX style]] programs gdb has a [[command line]] interface. [[ddd]] is a graphical wrapper for gdb, as well as some other debuggers.

==See also==
*[[Debuggers]] for a list of debuggers.

==External links==
*[http://www.gnu.org/software/gdb/gdb.html gdb Homepage]

Debuggers

2004-12-02T10:43:17Z

Dysprosia: Debuggers moved to Debugger

#REDIRECT [[Debugger]]

Template:Sandbox

2004-12-02T10:39:59Z

Dysprosia: add template

This is the '''LinuxQuestions.org sandbox''', where you can experiment with editing here, before you try editing the other articles, where no one will scream at you for messing things up.
----

LinuxQuestions.org Wiki:Sandbox

2004-12-02T10:39:02Z

Dysprosia: {{sandbox}}

User talk:Crazyeddie

2004-11-28T01:41:35Z

Dysprosia: Just noticed you signing personal comments. Does this mean LQ is not averse to opinion as say, Wikipedia would be?

Hello. Curious to know why you haven't tried Gentoo. Coming from slack, and showing interest in LFS, you may find Gentoo a decent middle ground between the two. I think it's a great distro...if you don't mind the long install. And their forums are one of the better forums out there. Anyway...back to the wiki.
[[User:Dkaplowitz|Dkaplowitz]]

----
I've heard of it, but haven't [had a chance|taken the time] to look at it. Slack just happend to be the first distro I was introduced to, and I found the lack of a package manager to be limiting. I'm working on LFS more for education purposes than anything else. As for other distros, I liked Mandrake 9.1 a lot, but I've heard bad things from a friend of mine about 9.2. After a bad week of cleaning malware off windows boxes, I decided to take an amble down the path of righteousness, and installed Debian. Like I said in the main page, Debian did somethings in the startup files that I didn't particullarly like. The default settings were perfectly alright, but I wanted it to do it my way. After some fumbling around I realized that I needed to know more about the inner workings of Linux, hence the LFS.

[[User:Crazyeddie|Crazyeddie]] 04:50, Mar 27, 2004 (EST)

----

Thanks for the update, I'll try and contact some of the MediaWiki developers and see if they can post to your mailing list, or contact Jeremy directly. [[User:Dori|Dori]] 21:07, Jul 5, 2004 (EDT)

----
Re [[Chown]], the point about dot files is important, but I think we should keep it just at [[Dot file]] ;) [[User:Dysprosia|Dysprosia]] 05:13, Aug 3, 2004 (EDT)

Fair enough. Somebody asked about it in the chown talk page so that's why it's there. [[User:Crazyeddie|Crazyeddie]] 15:14, Aug 3, 2004 (EDT)
----
Dan, might be an idea to remove this Redirect page you've just created - always handy to have them spelt correctly first :)

http://wiki.linuxquestions.org/index.php?title=Desktop_enviornment&redirect=no

Also - you have to manually note down what you've deleted in the deletion log --[[User:Skyline|Skyline]] 16:52, Aug 3, 2004 (EDT)

#yeah, it does help when you spell it right...
#okay, I'll go in and do that.
[[User:Crazyeddie|Crazyeddie]] 17:30, Aug 3, 2004 (EDT)

----

Howdy! I appreciate your contributions to the wiki!

Is there a different wiki we can put the hacker's jargon dictionary onto?

I feel like it's enough OffTopic that it shouldn't be here. I believe that there should be a wiki for it, or to complement the authoritative version, but I don't think it should be here.

-- LionKimbro

AFAIK, no. I originally planned to trim it down to just what I thought was on topic, but then I noticed a handful of LQwiki articles written on topics I had discarded. I'll lay off it for a while. A little bit of OTness doesn't hurt, just so long as it doesn't overwhelm the rest of the wiki. But it ''is'' getting close to that point. (One of the reasons I'm doing the [[Linux Documentation Project]] incorporation is to balance out all the OTness I'm inflicting on this wiki.) Dang thing is addictive though. If you find a particular article ''really'' offtopic, I'd guess you could nominate it for deletion... just as soon as we figure out a way to do that :-/[[User:Crazyeddie|Crazyeddie]] 18:34, Aug 4, 2004 (EDT)

Heh. Yes, it ''is'' addicting.

You might want to read some of the ideas we've had over on [http://communitywiki.org/ CommunityWiki] about how to work [http://communitywiki.org/ThePublicWeb the public web.]

I think that with time, there will be a "proper place" for just about everything. (See [http://communitywiki.org/TooFewWiki TooFewWiki] and [http://communitywiki.org/WikiProliferation WikiProliferation.])

Perhaps one of the most important developments for the wiki world would be [http://wikifeatures.wiki.taoriver.net/moin.cgi/NameSpacesForPages easy namespaces for pages.]

[[User:LionKimbro|LionKimbro]]

Well, I think hacker folklore has a place on this wiki, since programming, Linux, and hacking is interleaved. But this wiki shouldn't be ''only'' about hacker folklore. I do plan on eventually incorporating the entire File here, but we need to focus on our main mission first.

Wikis are great, because it allows users to contribute back to the community without much more knowledge than how to work a web browser in the first place. The main thing holding them back, as far as I can tell, is the lack of PHP coders to maintain the back end. (Plus people willing to pay for the hardware and bandwidth...)

I'm not so sure encouraging more NameSpaces is a good idea. I think they are good for keeping "administrative" areas of wikis seperate from the actual content, but any direct organization of wikis should be kept to a bare minimum. My experience with the [[Hardware Compatability List]] suggests that organizational schemes are the product of one or a few minds. Wikis naturally grow more organically, and one of the great things about wikis is the ability to random walk using the links (or, sometimes, the random page feature). Categories and other hierarchial organizational schemes are just too much work.

But maybe I misunderstand what you're trying to say. (Or I'm just plain wrong :-)). [[User:Crazyeddie|Crazyeddie]] 16:27, Aug 6, 2004 (EDT)

----
Hi Eddie. Yeah, I use this site as an information dump of sorts. Every time I do something that I don't think I'll remember next time I need it, I'll post it here. I read that you are also a debian user :-) I think Debian was the second distro I ever installed, it was potato. I've used many distros since but I always crawl back to debian. I'm currently working on a debian project. You might want to chek it out [[Installing woody|here]]. Well, anyways, thanks for the welcome! - [[User:Koody|Koody]] 08:45, Aug 8, 2004 (EDT)

----
I've just restructured [[LQWiki:Forums]] a little. It's just to keep Talk pages for discussion, and I've moved the preexisting archive to a dedicated archive subpage. Thanks [[User:Dysprosia|Dysprosia]] 02:46, Sep 1, 2004 (EDT)

Groovy [[User:Crazyeddie|Crazyeddie]] 17:32, Sep 1, 2004 (EDT)
----
Dan, the [http://wiki.linuxquestions.org/wiki/BullDog Bulldog] article has been edited in accordance with our ''Manual of style'' (as usuall..) - helps with consistency - btw, good work on TLDP email - thanks --[[User:Skyline|Skyline]] 08:21, Sep 4, 2004 (EDT)

Thought I got it right that time... [[User:Crazyeddie|Crazyeddie]] 12:21, Sep 4, 2004 (EDT)

----
== On copyright and intellectual property ==

Hi Dan, thanks for your advice on [[User talk:Sdrubble]] on Oct. 1. Got it only right now, and will do my best to keep it in mind from now on.

To be honest I feel sad about this kind of stuff. I don't personally believe on intellectual property [that's a spiritual discussion which does not belong here]; moreover, I was born and raised in a country where copyright laws do exist but are not taken seriously by common folks. A large corporation usually enforces this kind of stuff internally, but average Joes do not think twice before going to the copy shop next door (one or two on every block, believe me) and cloning a whole book or paying US$3 for a CD with Win XP for their home computer.

So in this particular Wiki case (where I can see that this kind of concern is taken VERY seriously) the effect it will have on me is that I won't feel as compelled as I was before to research bits of info and make it available here. I will certainly NOT spend my time emailing webmasters and requesting permissions to spread info that they themselves obviously want to spread.

However I also accept that the law is the law and should [... not 'MUST' ...] be followed, no matter what silly consequences might arise from that. So I'll keep my rebel lines of thought to myself and not materialize those onto unlawful actions (not on LQ, at least).

As a side note I personally believe that an approaching social evolution [you might read 'spiritual' instead of social, and 'revolution' instead of evolution] will soon turn all copyright, patent, intellectual property and similar concepts into curiosities from the past. Time should tell.

Keep your advice coming. It will be welcomed by the brain even when rejected by the heart.

Cheers

Sdrubble

----

Please write in the about section of wiki.lq.org what wikisoftware is used.
We use zope and I personaly do not like the usage of that software.
If this software supports ldap we could change to it...
--[[User:Phobie|Phobie]] 16:21, Oct 26, 2004 (EDT)

[[User:Jeremy|Jeremy]] is the one you'll have to talk to about that. Me and code don't get along so good. [[User:Crazyeddie|Crazyeddie]] 16:42, Oct 26, 2004 (EDT)

---------
Hi Dan, just now I saw your msg on [[User talk:Sdrubble]] on Oct 23. I'm not that a frequent visitor around here . . . :)

I'm from Brazil, and relax - no offense taken at all. It's a known fact that the Emperor of the US is the self-appointed Protector of the rest of world, although you don't usually find that statement in such a clear written form.

I'd not add anything to your list - as a matter of fact I'd just remove all items. ;) As the future Emperor of Planet Earth I will decree that all intellectual products are received from a Source higher than men's minds, and therefore the concept of IP is an aberration and an attempt at illegal appropriation.

Of course, no copyright laws shall remain after that, as well as no profitable software companies and also . . . uh oh, better stop right here.

Thnx for your answer, but you shouldn't bother replying to this anarchist any further . . . :))

Cheers

[[User:Sdrubble|Sdrubble]] Nov. 22, 2004
---------

Just noticed you signing personal comments. Does this mean LQ is not averse to opinion as say, Wikipedia would be? Is there some official guidelines/policy/arrangements about this? I am weakly in disagreement with personal opinion, but I'm not completely averse to it... [[User:Dysprosia|Dysprosia]] 20:41, Nov 27, 2004 (EST)

Text editor

2004-11-28T01:37:34Z

Dysprosia: alphabetise

A '''text editor''' is an [[application]] that is used to write and edit plain text. Text editors under Unix and Unix-like operating systems such as Linux are much more sophisticated than the default editors in other operating systems, in that these editors allow for more efficient editing, with extra features. These editors are not intended to be as simple or lightweight as the editors under Windows such as Notepad. However there are basic editors with a minimum of features if the extra power seems intimidating.

Under Unix and Unix-like operating systems, most system development and administration is done with text editing tools. Because of this there are many advanced editors available for Linux, which have a steeper learning curve for complete mastery. However, there is also a great number of simpler editors available for less advanced uses. Since so much of system administration is done by editing text files, your editor is one of your most important tools, along with your [[shell]].

As has been stated, their is a wide variety of editors available for Linux, to the point where it seems like every coder has created one at least once.

Many [[holy wars]] are fought over text editors. This is partially because they take time to learn, and when people invest that much time in something, they develop strong feelings about it. If this prospect dismays you, never fear because, as is almost always the case with Linux, choice abounds and very simple user-friendly editors are also available.

==Specific applications==

===CLI text editors===
* [[ed]]
* [[emacs]]
* [[joe]]
* [[nano]]
* [[pico]]
* [[vi]] and its derivatives

[[Keyboard shortcuts at a glance]]

===GUI text editors ===
* [[bluefish]]
* [[emacs]]
* [[kate]]
* [[kwrite]]
* [[Gedit]]
* [[gvim]]
* [[NEdit]]
* [[Composer]] (Comes with Mozilla)

==See also==
*[[Text Processing]]
*[[Word Processor]]
*[[WYSIWYG]]

Console

2004-11-28T01:35:22Z

Dysprosia: dont' make reference to people here

A console is a command line interface to a computer. All input and output to the computer is textual.

In the early days of UNIX, a console was a physical device a person would use to access a central computer. At first this was just a keyboard and basic line printer, screens came later. These devices were called ''teletypewriters'', or more comonly ''teletypes'' or ''tty''s. In those days UNIX was used on university [[minicomputers|minicomputers]], with several consoles connected. Below is a link to a picture of a [[PDP]]-7, where UNIX started life:

[http://www.faqs.org/docs/artu/graphics/pdp7.jpg PDP7]

The basic teletype of the late sixties influenced UNIX design principles in ways we see in [[GNU/Linux]] today. When you have a finite roll of paper to work on you want output to be terse, so UNIX programs say nothing instead of printing 'no output'. There are other reasons for this design decision - it makes the output form one program easier to parse as input to the next - but hardware limitations were certainly a factor.

Because in UNIX all devices are files, reading from a tty keyboard is the same as reading text from a file, writing to it is like writing to the file. This allowed technology of the day to be loosely coupled to the UNIX architecture, and more easily replaced when newer hardware came along. When monitors replaced printers as the main output device only a little software had to be rewritten because the programs did not rely on hardware specifics. To this day Linux calls the consoles tty, and the same files exist for reading or writing to them. Even if you never use them, there are files in <tt>/dev</tt> to support many teletypes, the command <tt> $ ls /dev | grep ^tty -c </tt> will output how many.

Fast forward to the present, the '''console''' (<tt>/dev/console</tt>) is just the tty that the system was booted from. Nowadays, it means the same thing as "[[terminal]]" (although there is also a <tt>tty</tt> command which reports back which tty you're currently logged in on). You can usually access teletypes one to six of a local machine (/dev/tty1 - /dev/tty6) by pressing Ctrl-Alt-Fn where Fn is F1, F2 etc.

On a typical machine running the [[debian]] stable [[Linux]] distribution, the first serial port is <tt>/dev/ttyS0</tt>. Many computers also have /dev/ttyUSB0 through /dev/ttyUSB15, a terminal may be connected in many ways and take many forms because the programs which use it do not rely on hardware specifics.





==See Also==
* [[CLI]]
* [[TV Typewriters]]

User talk:M00t00

2004-11-28T01:27:29Z

Dysprosia: greets/tip

Hi, welcome to the LinuxQuestions wiki. I'd just point out to you as a tip that you needn't (and shouldn't) sign articles, as your contributions are always listed in a page's history. Thanks [[User:Dysprosia|Dysprosia]] 20:27, Nov 27, 2004 (EST)

Proc

2004-11-28T01:26:40Z

Dysprosia: rm sig and tweak intro

The [[Linux]] operating system provides a pseudo-filesystem that provides an interface to kernel information, and to recieve information from a user or process.

The /proc filesystem started out as a way to find information about processes, but now it is used by just about everything for which implementing a system call would be a waste.

The filesystem is not itself on a disk, rather, it is in kernel memory, where the kernel and its modules control what is inside these files. When a file in /proc is read, a function or handler is looked up (from a table within the kernel), and that function will output information. Likewise, when a file is written to in /proc, a bit of the kernel will handle reading it in.

Some examples of /proc usage are /proc/cmdline, and /proc/config.gz. These provide two peices of information about the kernel, the "command line" (the parameters passed to the kernel at boot), and the configuration file. Of course there is also loadavg, partitions, swaps, version, uptime, and so on.

Also of interest is /proc/apm and /proc/acpi, for thier respective power management systems. Each one reports information about the state of power management, to be gathered by various programs/monitors. /proc/acpi is a directory, divided into subdirectories for each power device (fan, battery, button, and so on). Each subdirectory gives information about its device. /proc/apm is a 'file' which has information about the power, such as charge, the state of the ac-adapter, and time untill battery charged/drained.

The /proc filesystem is also used by many parts of the kernel for input and output.

GRUB howto and troubleshooter

2004-10-28T23:32:11Z

Dysprosia: #REDIRECT GRUB - keep information at the one place, please

#REDIRECT [[GRUB]]

Readelf

2004-10-28T05:06:22Z

Dysprosia: clean up

'''readelf''' lets you examine information about an [[ELF]] binary or object file. It however does not perform disassembly, use [[objdump]] for this purpose.

== Example usage ==
readelf -sW myobject.o | more

See also: [[Programming-related Commands]]

{{stub}}

ELF

2004-10-28T05:04:26Z

Dysprosia: rework

'''ELF''' ('''''e''xecutable and ''l''inking ''f''ormat''') is a format for storing binary executable or object data. It is very common, some Unix and almost all Unix-like operating systems (including Linux) support it natively.

==See also==
* [[Library-related Commands and Files]] - for more information on shared libraries.
*[[compile]]
*[[compiler]]
*[[source]]
*[[readelf]]

==External links==
http://www.theparticle.com/cs/bc/os/elfpecoff.html

Sysfs

2004-10-28T05:01:19Z

Dysprosia: spit it out

'''Sysfs''' can refer to the:
*[[sysfs file system]]
*[[sysfs system call]]

{{msg:disambig}}

Find

2004-10-27T06:33:29Z

Dysprosia: clean up some more. needs a description of the options and it's simple use also

'''<tt>find</tt>''' is a tool which allows primarily for the searching of files in a directory hierachy. It allows for versatile search criteria, for
formatted output, and for custom commands to be
run on search-results

==Examples==
If one wants to find and delete all old backup files from your vi or emacs edit sessions, but save directories that happen to end in a tilde

As root:

find / -type f -name "*~" -exec rm {} \;

That's it

Another example, if you wanted to perform a simple recursive grep:

find . -exec grep -H "searchtext" {} \;

Find also works well with [[xargs]]. Using xargs minimizes the number of times that [[grep]] or [[rm]] is run, speeding things up. The last commands could have been:

find / -type f -name "*~" | xargs rm
find | xargs grep "searchtext"

==External links==

*[http://man.linuxquestions.org/index.php?query=find&section=0&type=2 find man page]
*[http://www.gnu.org/software/findutils/findutils.html findutils web page]

Disk partitioning

2004-10-27T06:31:40Z

Dysprosia: clean up

'''Disk partitioning''' is the act of dividing a hard drive or other storage media into seperate sections, each behaving as if each section were on a seperate disk entirely. The BIOS of the computer is informed of the partitioning through a special area near the beginning of the hard drive called the partition table.

From an end user's point of view, partitioning is important because it can be used to create dual-boot systems and give older hardware access to more of the storage on newer hard drives. For example, a simple dual-boot partitioning scheme might have an NTFS partition containing Windows XP, a partition for a Linux root directory, a third partition for home directories, and a Linux swap partition.

On many systems, there is a maximum limit of four primary partitions. It is possible for each primary partition to be divided into numerous logical partitions, but this process can be tricky.

==See also==
* [[Disk and tape drive commands]] partitioning tools and techniques .

Partitioning

2004-10-27T06:30:22Z

Dysprosia: Partitioning moved to Disk partitioning

#REDIRECT [[Disk partitioning]]

Nice

2004-10-27T06:29:20Z

Dysprosia: ..

[[Category:Priorities]] [[Category:Tuning]]

Operating systems such as Unix and Unix-like systems such as Linux allows appling attributes known as ''[[priority|priorities]]'' which control how much time is given to a certain program in proportion to others.

Users can control priorities via the '''<tt>nice</tt>''' utility, that reports or sets the priorities, which is an integer between -20 and 19. It is called "nice" since the number that is given to a process determines how willing a task is to step aside and let other tasks monopolize the processor.

<tt>nice<tt> is used when a command is first run. For example, <tt>nice -n 19 setiathome</tt> would run [[setiathome]] with the lowest possible priority. Privileges are required to run a command with negative priority. To change the priority of a currently running process, use [[renice]].

Nice

2004-10-27T06:29:11Z

Dysprosia: use categories, not that silly member of thing

[[Category:Priorities]] [[Categories:Tuning]]

Operating systems such as Unix and Unix-like systems such as Linux allows appling attributes known as ''[[priority|priorities]]'' which control how much time is given to a certain program in proportion to others.

Users can control priorities via the '''<tt>nice</tt>''' utility, that reports or sets the priorities, which is an integer between -20 and 19. It is called "nice" since the number that is given to a process determines how willing a task is to step aside and let other tasks monopolize the processor.

<tt>nice<tt> is used when a command is first run. For example, <tt>nice -n 19 setiathome</tt> would run [[setiathome]] with the lowest possible priority. Privileges are required to run a command with negative priority. To change the priority of a currently running process, use [[renice]].