Announcement

**Qqmike** · Jun 08, 2011, 01:14 PM

Re: Commands at Konsole: Beginners: 3 parts

Part 2 Using Commands at Konsole
text files, file/folder commands, backups, ownership & permissions, mounting, flash drive problems

... in three parts Part 1; Part 2: Reply #1; Part 3: Reply#2

>>> Please post questions in the regular forum (i.e., not here) – Thanks

Contents:
-- Create a text file
-- Create a directory
-- Command Summary table: mv, mkdir, cp, rm
-- Making folder backups with cp -r
-- Copying hidden folders (and files): shopt -s dotglob
-- Navigating is the key: Use cd to get there; then use ls to see what's there
-- Ownership & permissions: the rules
-- chown & chmod: Setting ownership & permissions; diagnosing &fixing problems
-- Mounting filesystems /media, /etc/fstab, mount -a, /etc/mtab
-- Mounting in an emergency: Using a Kubuntu Live CD
-- Flash drive problems: mounting, ownership, permissions, unmounting
- - - - - - - - - -

Create a text file and directory: Practice

Create a text file
In Konqueror or Dolphin, to create a text file, right-click in a blank area and select Create New > Text file. Or, Edit > Create new > Text file.
To do it at Konsole, type
kate
Type some stuff in the empty text file opened by kate; then File > Save, specify the name TestFile and save it in /home/your_name/Desktop, then File > Quit. See it in GUI using Konqueror or Dolphin. See it in CLI using cd ~/Desktop, then list files using ls, as we do next:

The mv command: move; rename
Change directory into your Desktop (and remain there as your working directory). Then rename the file TestFile to myFile using the “move” command mv:
cd ~/Desktop
ls
mv TestFile myFile
The move command mv:
In a sense, you “move” the file into another name; you can use mv to rename directories; mv is also used to actually move files.

The mkdir command
While still in your ~/Desktop directory, using the “make directory” command mkdir, create a directory Folder1, then move myFile into it:
mkdir Folder1
mv myFile Folder1
Make another directory BigFolder and move Folder1 into it:
mkdir BigFolder
mv Folder1 BigFolder
The absolute pathname of myFile is
/home/your_name/Desktop/BigFolder/Folder1/myFile.

The cp command, cp -r
Backups:
Copy BigFolder and all its contents to a folder called BigFoldercopy:
cp -r BigFolder BigFoldercopy
This command also creates the new directory BigFoldercopy;
the -r means “recursively” and it ensures that the folder AND everything in it are copied.
BigFoldercopy is a “backup” copy of BigFolder. You may make up any folder name in place of BigFoldercopy; e.g., BigFolder_backup1. It's also useful to include the date in the folder name.
To ensure that hidden files and folders are copied, use it this way:
cp -RT BigFolder BigFoldercopy
=>
Hidden folders and files:
Copying hidden folders (and files): See below!

Commands: remove rm; remove directory rmdir
Finally, remove (delete) BigFolder using the “remove” command rm. (Make sure you are in the Desktop directory: cd ~/Desktop).
rm -r BigFolder
Again, -r ensures that the folder and everything in it are removed.
If BigFolder were already empty, you could use the “remove directory” command instead, as follows:
rmdir BigFolder
If you were not in the Desktop directory when you performed the remove rm command, but were somewhere else in the directory tree, use the full pathname of BigFolder:
rm -r /home/your_name/Desktop/BigFolder
If you were at the /home level (cd ~), you could do:
rm -r your_name/Desktop/BigFolder
with no leading slash in front of your name.
See what's left:
cd ~/Desktop
ls

SUMMARY of file/directory COMMANDS
cp, mv, rm, mkdir
(use man pages to see more; e.g., man cp)

>>> Practice these: change to your home or Desktop (cd ~ or: cd ~/Desktop), create some text files and some directories (file1, dir1, dir2/file2, etc.), practice each command. Use ls to see the results, and/or see it using Konqueror or Dolphin.

-- Copy files & directories cp
cp file1 file2 or cp -i file1 file2
copies file1 to a file called file2; if file2 already exists, it is overwritten by file1 contents; if file2 doesn't exist, it is created with the contents of file1;
option -i: interactive mode (you will be informed/asked).
cp file1 dir1
copies file1 into directory dir1 (the new file in dir1 is called file1, and so: dir1/file1);

Hidden folders and files:
Copying hidden folders (and files): See below!

Folder copying: cp -R dir1 dir2 (or cp -r dir1 dir2)
copies directory dir1 into directory dir2 (and so yields /dir2/dir1); if dir2 doesn't exist, it is created with the name dir2 and the contents of dir1 (NOT dir1 itself); the -R or -r = recursive and ensures that all the contents of dir1 are copied down to the lowest level subfolders and files.

Copy recursively, INCLUDING hidden folders and hidden files:
cp -RT dir1 dir2
This always copies the contents of dir1 into dir2 INCLUDING hidden files and hidden folders..
If dir2 does not exist, it will be created with the contents of dir1.
The statement
cp -r dir1/* dir2
will copy hidden folders and files if
shopt -s dotglob
is used (as a command or in ~/.bashrc), like this:
shopt -s dotglob
cp -r dir1/* dir2

See below for Wildcard and Copying hidden folders (and files).

Wildcard (see Part 3): * means zero or more characters. So dir1/* means all file/foldernames in directory1.
Assume dir2 exists:
cp dir1/* dir2
will only copy files in dir1 (at the top level) into dir2; it will not copy subfolders of dir1; it will not copy dir1 itself.
cp -r dir1/* dir2
copies everything inside dir1, down all levels of subfolders, into dir2; it will not copy dir1 itself.
cp -r dir1 dir2
copies the folder dir1 itself and all its subfolders and files into dir2, so the result is dir2/dir1.

Hidden folders and files: use of *
Copying hidden folders (and files): See below!

Backups
To make a backup of dir1, use: cp -r dir1 dir1_backup.
Then dir1_backup will be created and will have the same contents as dir1 and will be the backup of dir1. You can make up any name instead of dir1_backup.
-- Caution: If dir1_backup already exists (e.g., you did mkdir dir1_backup), and you do: cp -r dir1 dir1_backup, then you'll have a copy of dir1 inside dir11_backup: dir1_backup/dir1; that's OK, as long as you understand this.

To ensure that hidden files and folders are copied, use it this way:
cp -RT dir1 dir1_backup

Hidden folders and files:
Copying hidden folders (and files): See below!

-- Move, rename files & directories: mv
mv file1 file2 or mv -i file1 file2
file1 is renamed file2; but if file2 already exists, its contents are replaced by the contents of file1; option -i: interactive mode (you will be informed/asked)
mv file1 file2 dir1
move files file1 & file2 into directory dir1 (dir1 must already exist)
mv dir1 dir2
moves dir1 into dir 2 (and so /dir2/dir1) assuming dir2 already exists; if dir2 doesn't exist, dir1 is renamed dir2;

-- Remove files & directories: rm rmdir
rm file1 file2 or rm -i file1 file2
deletes file1 and file2; option -i: interactive mode (you will be informed/asked)
rm -r dir1 dir2
removes directories dir1 and dir2 and all their contents (-r = recursive => all their contents)
rmdir dir1 dir2
removes dir1 and dir2 assuming they are empty;

-- Create (make) a directory mkdir
mkdir dir_name
creates a directory called dir_name

Hidden folders and files, use of *: shopt -s dotglob
Copying hidden folders (and files)

Consider the statement
cp -r dir1/* dir2
which copies the contents of directory dir1 into directory dir2.
To ensure that the wild card * includes ALL files, including HIDDEN files and HIDDEN folders, you might run it this way:

shopt -s dotglob
cp -r dir1/* dir2

Or, edit your file
~/.bashrc to include the following:

# This ensures that * includes hidden folders and files
shopt -s dotglob

(Then File > Save, File > Quit)

Another way:
cp -RT dir1 dir2
has exactly the same end result as
shopt -s dotglob
cp -r dir1/* dir2

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Navigating is the key: cd and ls

Very important: Every command you issue takes effect relative to your current working directory. Your prompt (following the colon sign ( : ) or the command pwd (print working directory) both tell you where you are (= your current working directory).

Example: /home/your_name/folder1/folder2/file1 (= ~/folder1/folder2/file1)
-- To delete file1, you must be in folder2: use cd to get there. Let's say you are at home (~). Then
cd your_name
then
cd folder1
then cd folder2
Then to delete file1:
rm file1
-- To delete folder2, you must be in folder1: use cd to get there.
If you are in folder2, get to folder1 using
cd ..
(your working directory would be folder2 and the parent directory would be folder1; so cd .. means change directory to the parent directory = folder1; two dots = the parent directory of the working directory)
To delete folder2:
If it is already empty (i.e., file1 is deleted), then do: rmdir folder2.
If it is not empty, then first delete file1(see above), then do: rmdir folder1,
Before deleting folder2, regardless of where you are in the directory tree, you can get to folder1 using this absolute path:
cd /home/your_name/folder1

>>> Using list files ls: a very handy tool. (See man ls)
Each time you use cd to change into a directory, use ls to see the files and folders in that directory. Then you can work on files you see there, or use cd to change into a subdirectory.

Summary: Use cd to get there. Then use ls to see what's there.
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Ownership and Permissions Use ls -l to see them; chown & chmod to change them.

For every file, there are three classes of users:
The Owner (or User) of the file; The Group that owns the file; and Others--everyone else.
For a file, and for each of the three classes (owner, group, others), three file permissions are defined: read (r), write (w), and execute (x). Since a directory is a special type of file, everything here applies to directories also.
r, read
for a file, you can open it and read it; for a directory, you can list its contents (ls);
w, write
file: you can modify it, but can not change its name unless its parent directory has write permission; directory: you can add, delete, and rename files in that directory;
x, execute
for a file that is a program (or script), you can run the program; for a directory, you can enter it (change into it using cd) but can not list its contents unless it also has the read permission r.

Owner: By default, whoever creates a new file or directory is the Owner.
ls -l: list files, use a long listing format => shows ownership and permissions
Example: Create myFile as we did above (“Create a text file”), navigate to it, list it:
cd /home/your_name/Desktop
ls -l
-rw-r--r-- 1 mike mike 17 2008-12-17 05:37 myFile

The first 10 symbols are -rw-r—r--

The leftmost symbol tells you the type of file. This is a regular file indicated by the “-”.
(- means a “regular file”; d means directory; l symbolic link; c character device file; b block device file; you can see some of these is you cd /dev and do ls -l)

The next 3 symbols are read-write-execute permissions for the Owner; then 3 symbols for the Group; and 3 symbols for Others.
The Owner has rw-: read, write, but not execute; The Group has r--: read, not write, not execute; Others has r--: read, not write, not execute.
Then mike:mike means the Owner is mike (the leftmost mike); Group is mike (the rightmost mike).
The file size: 17 bytes. Then the date & time the file was modified. File name: myFile.

Setting ownership and permissions in GUI
Open Konqueror or Dolphin as root (kdesudo konqueror), navigate to the file or directory, right-click, Properties, Permission, make changes, OK. In Konqueror/Dolphin, click the Advanced Permissions button to see all nice choices owner, group, others and read, write, execute. Experiment with this, using a test text file you make. Check it at CLI using ls -l (after you navigate to its directory, like cd ~ or cd ~/Desktop) and in GUI using Konquero/Dolphin, right-click Properties > Permissions.

Setting ownership and permissions in CLI at Konsole: Use chown & chmod

Permissions – numerical mode
There are 8 possibilities (2*2*2) for read (on or off) - write (on or off) - execute (on or off) permissions on a file or directory (2*2*2 = 8 ). The octal equivalents for these binary numbers are:

0: ---; 1: --x; 2: -w-; 3: -wx; 4: r--; 5: r-x; 6: rw-: 7: rwx

Examples:
777 means that everyone (left-to-right: owner, group, others) can do anything (read, write, execute: rwx).
740: Owner can do anything, Group can only read, Others can do nothing.
755: Owner can do anything; Group & Others may read and execute (a program) but can not change it (can not write).
750: Owner can do anything (read, write, execute); Group can read and execute but not write; Others can do nothing.
754: Owner can do anything (read, write, execute); Group can read and execute but not write; Others can read but not write and not execute.

Diagnose PROBLEMS -- Folder & file problems

--- My directory (folder) is owned by root and/or with wrong permissions: I can't use it!
Suppose the folder is folder1 (and suppose folder1 is an absolute pathname starting at root (/) or is a folder in your ~ (home) directory (working directory)).
Ownership: change owner and group to mike
sudo chown -R -v mike:mike folder1
sudo is needed because until the command executes, root is the owner of folder1. The -R option means “recursively” so ownership is changed for the directory AND its contents. To see it work, use the verbose option -v. Afterwards, run “ls -l folder1” to see owner:group changed.
Permissions: If there's a problem with permissions, too:
chmod -v -R 770 folder1
changes the entire folder1 directory (including all its contents) to rwxrwx--- (for the owner mike, the group mike, and others).
--- Your file is owned by root. Change owner & group to mike:
sudo chown -v mike:mike /home/mike/my_file
Change permissions, as needed: chmod -v 770 home/mike/my_file
(no need for -R for a file; only with a directory)
--- You are owner (& group) of folder1, it contains file1, but you can't change the name of file1.
You need to change permissions on the folder to allow “write” (so you can change names of files & folders contained in it):
chmod -v 770 /home/mike/folder1
We don't use -R because we are only changing permission on the folder, not its contents (i.e., not on files in it); you don't need sudo because you own the folder.
--- You are owner (& group) of folder1, it contains file1, but you can't change file1.
You need to change permissions on file1 to allow “write”:
chmod -v 770 /home/mike/folder1/file1
--- Make a file executable: to make a file executable: chmod +x program_filename
(See tuxfiles for this “symbolic” mode)
--- Change group (to group1): chgrp group1 file_or_directory

Ownership & permissions
FIXING PROBLEMS -- SUMMARY Suppose file1 is contained in folder1.
-- To list the contents of folder1 (ls -l folder1), you must be in a class (owner, group, others) that has read permissions on folder1.
-- To change into the folder1 directory (cd folder1), you must be in a class (owner, group, others) that has execute permissions on folder1.
-- To change the name of file1, you must be in a class (owner, group, others) that has write permissions on folder1.
-- To read (open) file1 contents, you must be in a class (owner, group, others) that has read permissions on file1.
-- To change file1 contents, you must be in a class (owner, group, others) that has write permissions on file1.
-- If you do not own a file or folder, to mess with it you must use sudo: sudo chown; sudo chmod.

-- Project management
If you manage a project to read and change some files, one way is this: Put the files in a folder (or folders). Make yourself the folder owner; put the team members in the folder's group. On the folder, give yourself read, write, execute permissions (rwx); give the group read, NOT write, execute permissions (r-x) (so they can cd into the folder but can't change names of files or folders in it). Put the files in the folder. On the files, give yourself read, write, execute (rwx) permissions; give the group read, write, execute permissions (rwx) (so they can work with the files AND change them). Or, give group r-x (not write). Give “others” no permissions on the folder and files (---).
So, chmod on the folder: 750. On the files: chmod 770 or 750 (your choice).
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Mounting filesystems (/media, /etc/fstab, mount -a, /etc/mtab)

You can use the command line to mount and unmount devices, such as disk drives and flash drives, and when performing repairs/rescues using a Kubuntu Live CD.

For example, to write to a flash drive, it must be “mounted.” That means you must “attach” the flash drive's filesystem to a directory (folder) in your Kubuntu filesystem. When you open the Kubuntu directory, you will see the files on the flash drive and can work with them. That Kubuntu directory (folder) is called the mount point for the flash drive's filesystem. Mount points that are already made are in /media. The filesystems that are automatically mounted for you (by default) when you boot into Kubuntu are in the special file /etc/fstab (fstab = filesystem table). To make (force) your system to mount the filesystems in fstab, type the command mount -a or reboot. The filesystems that are actually mounted right now when you are working in Kubuntu are in the special file /etc/mtab. Good news: You can edit /media and /etc/fstab to suit you--adding or removing mount points in /media and in /etc/fstab.

GUI: To see how directories are mounted
Right-click on any directory (folder) in Konqueror/Dolphin, select Properties, and study the panel that pop up to see the mount point in the Kubuntu filesystem for that directory.

CLI: To see how directories are mounted
mount, cat /etc/mtab, cat /etc/fastb, df -hT
Have a look. Open Konsole, type
ls -al /media
Use Kate to look at fstab and mtab (then do: File>Quit), like this:
kate /etc/fstab
kate /etc/mtab
You can also see mtab by typing
mount
Another way to see your mount points:
df -h -T

To mount a device on the directory dir, the command is:
mount -t type [options] device directory
You may have to use sudo:
sudo mount -t type [options] device directory

Example: To mount a flash drive
mount -t ext3 /dev/sdc1 /media/flashdrive
or, use sudo (which is usually the case):
sudo mount -t ext3 /dev/sdc1 /media/flashdrive
(There are no options used in that command. The command mounts the flash drive's directory--partition 1 (sdc1)--on the folder /media/flashdive in the Kubuntu directory tree. The “t” means type of filesystem, which in this case is ext3.)

You can often omit the -t, options, type and write simply:
mount device dir
(e.g., mount /dev/sdc1 /media/flashdrive)

=> See man page for mount:
man mount
(very informative)

Important:
The folder /media/flashdrive must already exist before you issue the mount command. If it does not, then simply create a mount point for the flkash drive in media as follows:
sudo mkdir /media/flashdrive
(You must use sudo to create a (sub-)directory in the system directory /media. You can call the mount point anything you want; we called it flash drive, but you might use flash1 or usbFD1, etc.)

Mounting in an emergency: Using the Kubuntu Live CD

Let's say you must fix the GRUB boot menu file /boot/grub/menu.lst so your PC boots correctly, but you can't boot into Kubuntu to do that. Using the Kubuntu Live CD, open Konsole, type
sudo fdisk -lu
to see your drives. Suppose Kubuntu is the partition /dev/sdb3. Let's mount it, then open menu.lst in Kate:
sudo mkdir /media/sdb3Kubuntu
sudo mount /dev/sdb3 /media/sdb3Kubuntu
Thus, in your Live Kubuntu session, when you open the directory /media/sdb3Kubuntu (in Konqueror, Dolphin, or in Konsole), you will see and can access the entire Kubuntu filesystem on partition sdb3.
Open the boot menu, menu.lst, in Kubuntu on sdb3:
kdesudo kate /media/sdb3Kubuntu/boot/grub/menu.lst
(After editing, File > Save, File > Quit)
Then safely unmount the Kubuntu partition; note the spelling of umount:
sudo umount /dev/sdb3 /media/sdb3Kubuntu
Exit the Live Kubuntu session, re-boot your PC to see if you can boot into Kubuntu on sdb3.

(Notes: sudo is required to make a directory (mkdir) in the system directory /media and to mount or unmount the device /dev/sdb3 on that directory; we made up the directory sdb3Kubuntu to be the mount point, and we made it in the /media directory; we use kdesudo to open Kate because to edit the system file menu.lst we must use root; Kate is a graphical application (you can see it in GUI), so instead of sudo, we use kdesudo; we gave kate the full, absolute pathname for menu.lst file: start at /media/sdb3Kubuntu, which is the Kubuntu partition, then navigate in the Kubuntu root filesystem from root (/) to boot to the directory /grub and then to the file menu.lst)

Other command forms
-- You can shorten the umount command using:
sudo umount /dev/sdb3 or sudo umount /media/sdb3Kubuntu.
-- A more proper and complete mount command is:
sudo mount -t ext3 /dev/sdb3 /media/sdb3Kubuntu
The -t is “type of file” = filesystem type of /dev/sdb3; here type=ext3. You can use various commands (at Konsole in the Live CD) to find file type:
df -hT
blkid # and look for “Type=”

Exercise: Try this with your Live CD. Print this how-to, or use Konqueror web browser in Live CD to navigate here for these instructions. Do NOT actually edit your menu.lst though! Just look, then File > Quit.

Mount in GUI: In 8.04 and 8.10, there are also ways in Konqueror and Dolphin to mount filesystems (e.g., devices /dev/sdax). For example, right-click > Mount.

APPLICATION: Flash Drives
Flash drive problems: Ownership, permissions, unmounting

--- My flash Drive is owned by root and/or with wrong permissions for me!
(I can't add a folder or file to it or change a file on it.)
Suppose the flash drive is (mounted as) /media/sdc1.
(To see how it is mounted, use mount or cat /etc/mtab.)
To see who own it:
ls -l /media

Ownership: change owner and group to mike
sudo chown -R -v mike:mike /media/sdc1
sudo is needed because until the command executes, root is the owner of the folder sdc1. The -R option means “recursively” so ownership is changed for the directory sdc1 AND its contents. To see it work, use the verbose option -v.
Check it:
ls -l /media
(or do: cd /media and ls -l)
***=> If you are unable to change ownership as indicated, change ownership of the CONTENTS of the folder /media/sdc1:
sudo chown -R -v mike:mike /media/sdc1/*

Permissions: change to rwxrwx---
sudo chmod -v -R 770 /media/sdc1
changes the entire sdc1 directory (including (recursively -R) all its contents) to rwxrwx--- (for the owner mike, the group mike, and others).
Check it:
ls -l /media
(or do; cd /media and ls -l)
Unmounting: When done, unmount the flash drive:
umount /media/sdc1
***=> If you are unable to change permissions as indicated, change permissions of the CONTENTS of the folder /media/sdc1:
sudo chmod -v -R 770 /media/sdc1/*

-- My flash drive won't mount
In GUI, try to right-click on its icon, the Mount.
In CLI, at Konsole, try:
sudo mount -a
then see if it's mounted. Or, as above, create a mount point for the flash drive and use mount; assume it is seen as /dev/sdc1 in Kubuntu, then:
sudo mkdir /media/flashdrive
sudo mount -t ext3 /dev/sdc1 /media/flashdrive

-- My flash drive won't unmount; I get some scary error message!
Assume you are in your home directory(cd ~). Look in mtab to see how the flash drive is mounted:
cat /etc/mtab
Example:
/dev/sdd1 /media/usbdisk-1 ext2 rw,nosuid,nodev 0 0
Looks like it is mounted as /media/usbdisk-1. Try to unmount it:
umount /media/usbdisk-1
umount: /media/usbdisk-1 is not in the fstab (and you are not root)
Ooops, I better try this as root:
sudo umount /media/usbdisk-1
Then in GUI select “Safely Remove.” => Done!

Note:
To see how the flash drive is mounted, you could also use
df -h -T
or
mount

Note: mount -a
To mount all devices listed in your filesystem table /etc/fstab, issue this command:
mount -a
or
sudo mount -a

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End of Part 2 Using Commands at Konsole

Part 3: See Reply #2 below --> ...

**Qqmike** · Jun 08, 2011, 01:14 PM

Re: Commands at Konsole: Beginners: 3 parts

Part 3 -- Neat Stuff and Methods

Commands at Konsole
... in three parts Part 1; Part 2: Reply #1; Part 3: Reply#2

>>> Please post questions in the regular forum (i.e., not here) – Thanks

Contents
-- Linux directory tree: man hier
-- History: command history; Up & Down Arrow
-- Alias: make your own command alias name='command'
-- Checksums: md5sum filename

-- Wildcards: * ? [...] {...}
-- Using * in cp, rm: hidden directories (shopt -s dotglob)
-- Removing files and directories: rm, rm -r or rm -R, rmdir
-- Copy files and directories cp, cp -r or cp -R
-- Example: Copy GRUB files using cp
-- Example: Backing up your home data using cp

-- Type of file: file
-- Finding files and folders: cd / && sudo find -name name_of_file
-- Stop the running command (process): Control+C
-- Running processes: top
-- Troubleshooting: dmesg
-- Re-start or turn off computer sudo shutdown -r [-h] now
-- Superblock of filesystem: sudo dumpe2fs -h /dev/sdxn

-- Grep: Search through text for a string
-- Using more than one command at a time: ; && || and pipe |

-- Extract files from an .iso without burning the CD
-- Initrd -- opening
-- Tar files: Viewing the contents
-- Chroot into a partition
-- Environment Variables printenv; echo $PATH
-- Example: Working at a prompt: a gparted screenshot
-- NEW (added): Tab completion saves time & typing
-- NEW (added): Empty Trash (at Konsole)

NEW:
-- APT Commands A Summary Sheet

REFERENCES

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Linux directory tree
Command:
man hier
See: Filesystem Hierarchy Standard: http://www.pathname.com/fhs/

Command History
Command:
history
Also, hit Up & Down Arrow keys
To repeat the recent commands you issued, press the Up Arrow key. Use Up & Down Arrow keys to scroll commands; stop and press Enter to execute the command or edit the command and press Enter to execute it.
To list all past commands you used at Konsole, use the history command:
history
I got 503 lines. Line 502 was
502 man whatis
To execute command 502:
!502
To Clear History in Konsole, use Edit (tab at top).

-- Example: Using history Up Arrow with Tab completion to save typing.
Suppose in your current working directory, you have two folders to delete, folder1xy6zdir7g-1 and folder1xy6zdir7g-2. One way to do it:
List the files in the working directory to them:
ls
rm -r fol<Press the Tab key now>
That returns:
rm -r folder1xy6zdir7g
and you then finish it with:
rm -r folder1xy6zdir7g-1
and press Enter to remove that folder and all its contents (-r = recursively).
Then press the Up Arrow key and you'll see your prompt change to its history one command in the past:
rm -r folder1xy6zdir7g-1
Before pressing Enter, edit that to read
rm -r folder1xy6zdir7g-2
and press Enter to delete that folder.
Note that
rm -r folder<Press the Tab key now>
uses Tab-completion (see toward the end of Part 3 below). It means: type the letters “fol” and press the Tab key (do not type the symbols < or >) and BASH will continue typing for you.

''alias'': make up your own command
The alias command lets you define a new command. Example: ls -alr means list all files in long form and in reverse order. Define a command, say lm:
alias lm='ls -r'
Then, you may use the command lm as you would use ls -alr.

Checksums: md5sum filename
After downloading a file (e.g., Kubuntu iso), run the following command to compute the MD5sum:
md5sum filename
Compare the result to the md5sum posted at the site.
-- Example: GParted Live CD
I downloaded the iso file gparted-live-0.3.9-13.iso to folder /home/mike/Desktop/gpartedCD
Change into that directory and run the md5sum command:
cd /home/mike/Desktop/gpartedLiveCD
md5sum gparted-live-0.3.9-13.iso
Output:
dd63e0bf1c6b71add7e5b40656ec84c4 gparted-live-0.3.9-13.iso
Compare to the value at the GParted site:
MD5SUMS dd63e0bf1c6b71add7e5b40656ec84c4 gparted-live-0.3.9-13.iso
They match => the download is good.
If they did not match, you should return to the site and download the file again.

Wildcards * ? [...] {...}
A wildcard is a special character you can use in a filename.
* means zero or more characters.
? means exactly one character; ?? means two characters; etc.
[characters] means exactly one character listed:
A character may be a letter (a-z, A-Z) or a numeral (0-9).
You can use a range, like d-k or 2-5.; or a list like [defghijk] or [2345].
[!characters] means any character that is not listed.
[!0] means any nonzero character.
{word1,word2,word3} means exactly one word listed.
-- Example: cd ~/Desktop && ls K*[0-9]
means change to your Desktop directory, THEN list all files that start with a K and end with a numeral between 0 and 9.
-- Examples: See Removing files and Copy files below:

IMPORTANT:
Using * in cp, rm: hidden directories (shopt -s dotglob)
To ensure that the wild card * includes HIDDEN folders and files, include the following statement in your file ~/.bashrc:
shopt -s dotglob
Or, use it like this:
shopt -s dotglob
cp -r dir1/* dir2
Or, use this statement (which has the same end result):
cp -RT dir1 dir2
(to copy ALL contents of dir1 into dir2).

Removing files and directories: rm, rm -r (or rm -R), rmdir
cd dir1
rm *
means change into directory dir1 and remove every file. It will not remove any subdirectory of dir1.
rm -r *
means remove all files and (sub)directories recursively: it will empty ALL contents of dir1; but it does not remove dir1 itself. Thus dir1 still exists but is empty.

-- To remove dir1 itself:
After issuing cd dir1 and rm -r *, then dir1 is empty, so you can change to its parent directory and remove dir1:
cd ..
rmdir dir1
The command to remove directory, rmdir, works only if the directory to be removed is empty.
-- To remove dir1 and all its contents in one step, you must first be in its parent directory, then issue
rm -r dir1
That removes dir1 and all its contents (files and subfolders and their contents) from the filesystem.

Copy files and directories cp, cp -r (or cp -R)
cp -r folder1/* folder2
means copy all the contents of folder1 into folder2 but NOT folder1 itself.
cp folder1/k*.txt folder2
means copy all files in folder1 that begin with a “k” and have the .txt extension into folder2.
cp folder1/*kubuntu* folder2
means copy all files in folder1 that have the word “kubuntu” in their filename into folder2.

> You can use wildcards with other commands (e.g., mv, ls) just as we did with rm and cp.

Example: Copy GRUB files
In Kubuntu, the (13 or so) GRUB files are at /boot/grub. Suppose you wish to set up /boot/grub in another directory called targetdir. Assume targetdir is either an absolute path or that it is in your current working directory. E.g., targetdir may be the first partition of a flash drive mounted as /media/sdc1. So the goal is: targetdir/boot/grub (with all the GRUB files copied into this new grub directory). Here's how.
(Assume you own the flash drive and have all permissions; if not, you must use sudo in front of commands.)

Solution #1: The safe way.
mkdir targetdir/boot
mkdir targetdir/boot/grub
cp /boot/grub/* targetdir/boot/grub
copies all the files in /boot/grub (of Kubuntu) into the directory targetdir/boot/grub.
Note: Change directory (cd) and list files (ls) to check your results, like this:
cd targetdir/boot
ls
cd grub
ls

Solution #2
Create a boot directory in the targetdir and copy the grub folder and all its contents into it:
mkdir targetdir/boot
cp -r /boot/grub targetdir/boot
(or cp -r /boot/grub/ targetdir/boot)
The result will be targetdir/boot/grub (and all the files in grub). Since there is no grub directory in targetdir/boot, a directory called grub is created, and the grub files (from /boot/grub in Kubuntu) are copied into it. The recursive option -r means to copy the folder grub and its contents.

Caution: Subtleties
If you omit mkdir targetdir/boot, and then do: cp -r /boot/grub targetdir, you will get targetdir/grub (and the GRUB files copied into it)--you will NOT get targetdir/boot/grub! Also:
cp -r /boot/grub grub
will create a new folder called grub (in the working directory) and copy grub files into it; however,
cp -r /boot/grub boot/grub will NOT create boot and then create boot/grub!

=> Make up some text & directory files in your /home or Desktop and practice!

Example: Backing up your home data using cp
-- Assume your OS is messed up and you will re-install it or delete it; but your /home/your_name is in the same partition as Kubuntu. Use a Live CD; if Kubuntu is mounted as /media/sdb2 and your flash drive as /media/sdc1, to copy your home to a flash drive:
sudo cp -r /media/sdb2/home/your_name/* /media/sdc1/
(/dev/sdc is also correct, without the ending slash)
-- If you are able to boot into Kubuntu, to copy all directories and files in your home to a flash drive (sdc1):
cd /home/mike
cp -r * /media/sdc1

Type of file: file filename (the command is file; the argument is filename)
Tells you the type of file that filename is.
Examples of file types: ASCII text, data, application, JPEG image data, C program text, block special, data, x86 boot sector, Linux/i386 ext2 filesystem, x86 boot sector, extended partition table, Linux/i386 swap file.

Very Useful:
Finding files and folders (see the symbol && below)
Command:
cd / && sudo find -name name_of_file
Ex: cd / && sudo find -name device.map
Output: ./boot/grub/device.map
(the leading dot means “working directory” = root = / (since we did changed into root using cd /))
Specify a directory to search by placing the directory name after "find" and before "-name":
Ex.: cd / && sudo find /boot -name stage1
Output: /boot/grub/stage1

Stop the current running command
Ctrl-c: Stop the current running command
You can use this if you started a command running for a lonmg time and you wish to terminate it AND you know it is safe to do so and will not mess up your system.

Running processes: top
Command top shows the running processes in descending order of resource usage. Leave that window running. When the system "hangs," top shows the resource hogs.

Troubleshooting (e.g., kernel panic): dmesg
dmesg > reportfile
will print the results to the test file reportfile in the working directory.
Here's another:
tail -20 /var/log/dmesg
will print the last 20 lines of the log dmesg to the screen;
tail -20 /var/log/dmesg > mesg_report.txt
will print the last 20 lines of the log dmesg and redirect the output to a text file called mesg_report.txt.

Re-start or turn off computer
sudo shutdown –h now (for power off, halting)
sudo shutdown –r now (for rebooting)

Superblock of filesystem: sudo dumpe2fs -h /dev/sdb3
To check the superblock of filesystem on sdb3, mount history, block size, etc.

Using more than one command at a time
semicolon ; && || and pipe |

command1 ; command2
means to execute command1 then execute command2.
command1 && command2
means to execute command1; if and only if command1 executes successfully, then execute command2.
Example: see “Finding files and folder” above.
command1 || command2
means execute command2 only if command1 fails.
Note: the symbol | is above the “\” symbol on your keyboard (vertical “pipe” symbol); here, you need two of them: || . (So: Shift+|)

Pipe |
When you need the output from command1 for the input into command 2, then you would use the pipe operator '|'. You can send the output of a command to be the input of another command using a pipe symbol | , and doing so is called “piping.” The syntax for piping:
command1 | command2
-- Example:
To print the Master Boot Record of drive sda to the screen:
dd if=/dev/sda bs=512 count=1 | hexdump -C
The standard output of the dd command is the input for the hexdump command (see man hexdump).
See “Example: Piping, grep -i, cat, redirection >” below.

Search through text for a string: grep
Command: grep "some string" somefile
-- Example: grep "Linux" /home/mike/testfile
will search for the string Linux in the file testfile. Command grep examines each line of data it receives from standard input and outputs every line (to standard output = the screen) that contains a specified pattern of characters. See man grep.
See next Example.

Example: Piping, grep -i, cat, redirection >, less
See Part 1 for redirection > and cat and less
-- Exercise:
Navigate to your Desktop (cd ~/Desktop), and use Kate to make a file (see Part 2) called MyFile.txt, and include, say 15 or 20 lines (press Enter after each line) of any text you wish to type, but include the word Dog on two lines, the word dog on one line, and the word DOG on one line. You are still in /home/your_name/Desktop.
Use cat to see the file:
cat MyFile.txt
Use less to see it (then press q to quit):
less MyFile.txt
The command grep is used to search a file for a string of text that you specify (see man grep). Let's display your file on the screen and pipe that output (standard output) to become the input to the command grep, and we'll use grep to search for the word dog:
cat MyFile.txt | grep dog
(I got 1 line

dog is king
Now search for Dog:
cat MyFile.txt | grep Dog
(I got 2 lines

Dog is here now!!!
Dog is also here at the same time
Search for DOG:
cat MyFile.txt | grep DOG
(I got 1 line

DOG is in this line of text

Command grep is case sensitive!
You can use the option -i to make grep case insensitive as it searches your file for various forms of dog:
cat MyFile.txt | grep -i dog
This time I got all 4 lines:
dog is king
Dog is here now!!!
DOG is in this line of text
Dog is also here at the same time

-- Pipe: redirect to a text file
To have a text file copy of your search results, you can redirect the output of grep to a file in your Desktop (since that's the working directory) called, say, dogFile:
cat MyFile.txt | grep -i dog > dogFile
(In place of dogFile, you could specify any path, like an absolute path to /Folder1/Folder2/myDogFile:
cat MyFile.txt | grep -i dog > /Folder1/Folder2/myDogFile)
=> See Part 1 for redirection >.

Extract files from an .iso: Access iso files without burning the CD
Here's how, using an example.
The goal is to copy some files off an iso file WITHOUT having to burn the iso to make a Live CD.
Download the iso file to your Desktop folder.

(=> If it's a tar.gz file or similar, get the iso by right-click, Extract Here, or use ARK under K > Applications > Utilities > Archiving Tool (ARK).)

Example: Let's say the file name is kubuntu-8.10-desktop-i386.iso and it's in my Desktop folder:
/home/mike/Desktop/kubuntu-8.10-desktop-i386.iso

Make a directory /media/test for your mount point
sudo mkdir /media/test

Mount the iso on the directory /media/test: this is the KEY command!
sudo mount -t iso9660 -o loop /home/mike/Desktop/kubuntu-8.10-desktop-i386.iso /media/test

You may change directories (cd /media/test) and list all the files (ls -a) to see what's there.
Or, use the absolute path: ls -a /media/test
Now you may copy (cp or cp -R) files and folders in /media/test.
Assume you copy them into a new directory /tmp/new_folder. (Using mkdir & cp)
Then change the ownership so you (mike) can have these files and then unmount it:
sudo chown -R mike:mike /tmp/new_folder
Unmount /test:
sudo umount /media/test
If you have to invoke root, use sudo (as I have above, when it was necessary).
Now you (the owner) may do whatever you wish with the files & folders in /tmp/new_folder.

Initrd--opening

Sometimes you may have to examine or even patch the important file initrd, especially if doing work with bootloaders, kernels, building flash drives or live CDs and live USBs. Here's how to open an initrd.gz file. To avoid working as root directly with your files under /boot (including initrd), let's illustrate this by working safely on your Desktop. Sometimes, initrd may be under a Casper directory (e.g., on a live CD). As an example, you may first open an iso file, then access an initrd contained in a folder of the iso. See topic above for opening an iso.
Tip: As you go along, use your GUI and file manager to see what's happening after each command.
Note: In this example, initrd.gz represents your initrd file. For example, initrd.gz may be initrd.img-2.6.24-23-generic.
Caution: Be real careful messing with the important system file initrd! You can easily break your system.

> Create a safe place to work.

Log in to your working Kubuntu operating system.
On your Desktop, create a folder to work in, say work_here:
Right-click on Desktop, Create New > Folder, and type work_here for “Enter folder name.”
Alternatively, do this at Konsole, at your home directory prompt:
mkdir /home/your_name/Desktop/work_here

> Copy the initrd file to work_here
You can do this in GUI or at Konsole. You may want to create a backup for the original initrd file, call it initrd.gz.backup.
At Konsole:
cp /path/to-initrd/initrd.gz /home/mike/Desktop/work_here
(e.g., cp /boot/initrd.img-2.6.24-23-generic /home/mike/Desktop/work_here)

> Open Konsole and get ready to work.
K > System > Konsole. To become root, type
sudo su
Navigate to the folder work_here:
cd /home/mike/Desktop/work_here

> Extract initrd.gz (it is a compressed file and has been compressed by the algorithm called gzip).
Type the following command to do this:
gzip -dc initrd.gz | cpio -i

Now if you look in the folder work_here, you'll see all the extracted files and folders.
(You can do so in GUI or at Konsole by typing ls -al )

> Edit the broken file that's causing the problem.
You should still be in the folder work_here. Suppose that file is /somefolder/somefile.
Open the file in kwrite (or kate):
kwrite somefolder/somefile
Make your changes to somefile, then File > Save, File > Quit.

> Zip the new initrd.gz file.
Still at Konsole, you should still be in the folder work_here. Issue this command at Konsole:
find . | cpio -o -H newc | gzip -9 > initrd.gz
(Note This reads as follows: find then space then a period then space then the vertical pipe bar etc--don't omit the "dot" after find then space)

> Put it back together in its original location.
cp initrd.gz /path/to-initrd/initrd.gz

(Note: You should still have a root prompt, and you MAY need it because you are modifying initrd in some boot folder (or Isolinux or Caper folder). Again, to see what's going on or if you get stuck on something, you can always check things in GUI, starting by opening Konqueror as root in another instance of Konsole by typing the command kdesudo konqueror, or if you wish, kdesudo dolphin.)

References
cpio
http://www.gnu.org/software/cpio/manual/cpio.html
gzip
http://www.gnu.org/software/gzip/man...ip.html#Sample

[End of topic: Initrd -- opening]

Tar files: Viewing the contents
Software is often distributed as a gzipped tar file compressed with gzip. (Linux/Unix: “tar” = “tape archive”). These files have extensions tar.gz or .tgz. To view the directory of such a file:
tar -tzvf name_of_file.tar.gz | less
For more info: man tar
Example: Super Grub Disk source code
tar -tvf public_super_grub_disk_source_code_0.9774.tar.bz2 | less
(For bz2, don't use the option z) We piped the output to less.
To navigate less output:
Use Page Up, Page Down, Up, Down
G (go to the end of the file)
1G (go to the beginning)

Chroot
To “chroot into a partition” is to enter the partition with root privileges (“as root”). (The root directory is set equal to the partition.)
Here's how:
Let's say Kubuntu is in partition sda2, something is broken there, and you need to use your Kubuntu Live CD to chroot into sda2 and fix the problem. From the Live Kubuntu CD at Konsole:
sudo mkdir /media/fixthings
sudo mount /dev/sda2 /media/fixthings
sudo chroot /media/fixthings
=> Now you are “in” sda2 “as root” and can work from there as if you were actually booted into it. The command prompt is a root prompt “... :/#” You can enter the commands you will use to fix the problem in sda2. When done, type exit to leave the root prompt:
exit
Now the prompt is a regular, non-root prompt “... :~$”
To be safe, unmount the partition:
sudo umount /dev/sda2 /media/fixthings
=> CAUTION Do not use chroot unless you know what you aredoing; you can damage your Kubuntu filesystem if you make a mistake while using chroot.

Environment Variables printenv; echo $PATH
Environment variables are used by various processes running while you are logged into your Kubuntu account. To see yours, type
printenv
and you will notice many familiar environment variables, such as PWD (present working directory), HOME (your home), USER (you), etc. Notice SHELL=/bin/bash, which tells you that the bash program is in directory /bin.
An important environment variable is PATH; mine says:
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
You can also see PATH by typing
echo $PATH
PATH specifies the places the system looks when you try to run a program (an executable file). The system starts from the left, /usr/local/sbin, and works to the right until it locates the program you are trying to execute. Open Konqueror/Dolphin, have a look at these places. For example, navigate to /bin where you can see bash and a bunch of familiar commands (executable programs, indicated by a blue gear). The command date is one such program.
Run (execute) date in two ways (in Konsole):
date
/bin/date
Because (the small utility) date is in your environment variable PATH, you can type simply “date” (and not /bin/date) to execute it.
=> If you are unable to execute a program you KNOW you have (and get “Command Not Found”), it is because the location of the program is not included in your PATH environment variable.
Changing Path, adding /new/folder/here to it:
PATH=/$PATH:/new/folder/here

Working at a prompt in an application: a gparted screenshot example

Now and then, in an application, you'll find you need a command line to do something. Here's an example. Suppose in GParted Live CD or in gparted (from Kubuntu), you need a screenshot. While in GParted, take the screenshot following directions there, and it will be saved in /root for you. That is the /root within the GParted program (on disk or in RAM), NOT in your Kubuntu filesystem. Here's a way to get the screenshot onto your flash drive:
In GParted, click Terminal icon. You get a prompt, like this:
root@debian:~#
Make sure you are in root and ls files to see the screenshot (called gparted.jpeg):
cd /
ls
Output: gparted.jpeg
Plug a flash drive into a USB port and make GParted see it:
GParted (tab at top left) > Refresh Devices (and check the drop-down list at upper right of GParted screen). Suppose the flash drive is sdc1. Make a directory for mounting the flash drive:
sudo mkdir /root/flashdrive
sudo mount /dev/sdc1 /root/flashdrive
Copy the screenshot into the flash drive:
cp gparted.jpeg flashdrive
Check that it is in the flash drive:
cd flashdrive
ls
gparted.jpeg
Unmount the flash drive:
sudo umount /dev/sdc1 /root/flashdrive
When you exit GParted, the screenshot will be on your flash drive as the file gparted.jpeg.

NEW, Added:

Tab Completion – Typing made easy while navigating

When typing file and directory names, you can sometimes use tab completion to make typing easy and fast.
Suppose you have the following directories:
/home/your-name/Desktop/xyzTest-Folder.21t-D3.26linux/whyld47yt-69.3G
along with many other files & folders in the Desktop folder. To “drill down” to the file or folder whyld47yt-69.3G, try using tab completion:
Starting at your home (cd ~),
cd Desktop
and list files to see what's there:
ls
where you see the folder xyzTest-Folder.21t-D3.26linux
To change directory into the folder xyzTest-Folder.21t-D3.26linux, try this:
cd xyz<Press Tab key now>
(but do not type the symbols < or >)
You should see that the rest of the folder name is automatically completed for you after you hit Tab.
To accept it, press Enter. To see what's in the folder xyzTest-Folder.21t-D3.26linux, list files again:
ls
You'll see all the files and folders contained in xyzTest-Folder.21t-D3.26linux, including the folder whyld47yt-69.3G, so again type
cd wh<Press Tab key now>
and see the Tab-completion take place automatically:
cd whyld47yt-69.3G
and press Enter to accept it.

Tab-completion choices
Suppose two files (or folders) have similar names; e.g., whyld47yt-69.3G and whyld47yt-610.3G.
If you type
cd why<Press the Tab key>
you'll get:
cd whyld47yt-6
at which time you may type either 9 or 10 and press Tab again to complete the name.

Editing Tab-completion entries
After using Tab-completion, you may edit the name that results before pressing Enter to accept it. You may also use Tab-completion more than once—even repeatedly—to “get” the full name you are after in a command line.

Navigating: Thus, use cd, ls, and tab completion to navigate quickly and easily through the filesystem.

NEW, Added:

Empty Trash
It sometimes happens that you are unable to “Empty Trash Bin.” Or, you delete something, but it doesn't appear in the Trash Bin. Such items are here:
/home/your_name/.local//share/Trash
where you will see two folders: files and info. The directory called files contains deleted folders/files; and info contains information about such deleted items.
You can manually empty files and info as follows:
cd /home/your_name/.local//share/Trash
ls
files info
sudo rm -r files/*
sudo rm -r info/*

In fact, you may remove the entire folders files and info and they will be re-created as they are needed; i.e., as you delete items:
sudo rm -r files
sudo rm -r info

NEW ADDED:

APT: Advanced Packaging Tool

-- APT Commands -- A Summary Sheet

Help:
apt-get help
man apt-get

Root: Run the APT commands below using root; i.e., by first typing sudo.

Sources (of packages)
/etc/apt/sources.list –> where to look for and get packages
http://packages.debian.org/stable/allpackages.html∞ – all Debian packages

All packages on your system: dpkg -l
Print this list to a file: dpkg -l > MyListDebian.txt

apt-get update
Run this after editing source.list and before using apt-get.
Run this before running apt-get install.

More on searching for packages and version information
> Run apt-get update, then:
> Search: apt-cache searchname_of_package
> find out which packages have new/newer versions (first install apt-show-versions):
apt-show-versions -u
> list of all packages, that contain or address "Kubuntu" is obtained by:
apt-cache search kubuntu
> for more information on a particular package, you can use:
apt-cache show name-of-package
> All installable versions of a package (they depend on your sources.list) can be listed by typing:
apt-cache policy name-of-package

General

First:
apt-get update
Search:
apt-cache search package_name
Install:
apt-get install package_name
Remove:
apt-get remove package_name
apt-get --purge remove package_name
(--purge: deletes config files, too)
Clean:
apt-get clean
(cleans /var/cache/apt/archives where packages are first downloaded)
apt-get autoclean
(removes old package files, out of date, no longer useful)
Find:
> Start at root:
cd / && sudo find -name name_of_file
> Start at directory dir:
cd / && sudo find -name dir name_of_file

.deb packages
Installing .deb packages that are already downloaded to you:
dpkg -i package.deb

- - - - - - - - - -
Repair APT

This may be a “best” choice:
apt-get -f install

There are two separate commands:
dpkg –configure or dpkg –configure -a
(configures unconfigured packages)
dpkg-reconfigure or dpkg-reconfigure -a
(reconfigure already configured packages)
-a option
with the -a option, both commands will configure all packages that meet the criteria
(NOTE: dpkg-reconfigure -a may take a while)

Usual scenarios where you want to use them:
dpkg --configure -a
When upgrade has been interrupted by errors or crash, to complete the installation of packages
dpkg-reconfigure package_name
When you want to change the package behavior, it will ask debconf questions (again)
so you can change your answers and modify the configuration

sudo apt-get update
This refreshes the package list and info from the repositories

sudo apt-get upgrade
this finds, and lists the available updates.

Adept/apt-get repair, another approach:

Close all windows that have anything to do with installing packages, close Adept, open your Konsole, and enter 3 commands:
sudo dpkg --configure -a
sudo apt-get update
sudo apt-get install

Others to use:
sudo apt-get autoclean
sudo apt-get -f install This may be a “best” choice (?)
sudo apt-setup

dpkg
Damaged or Interrupted (when using apt-get):
At Konsole, run sudo dpkg --configure -a

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

End of Part 3

REFERENCES

Tuxfiles: http://www.tuxfiles.org/
Psychocats: explains “Running sudo graphically” using kdesu/kdesudo;
http://www.psychocats.net/ubuntu/graphicalsudo
Nice links:
https://help.ubuntu.com/community/CommandlineHowto
https://help.ubuntu.com/community/Ad...mmandlineHowto
Advanced, neat commands: Command Line Kung-Fu:
http://www.commandlinefu.com/command.../sort-by-votes
More References:
Bash Reference Manual
http://www.gnu.org/software/bash/manual/bashref.html

File Management
http://polishlinux.org/console/file-...ment-in-linux/

- - - - - - - - - - - - - - - - - - - -

Addendum:

A permissions calculator for the chmod command

Permission calculator
http://www.robolink.co.uk/calculators10.htm

You don't really need this, of course, but it's sorta fun; and you can mess with it to see some common combinations. (Of course, if you use Firefox with NoScript, make sure NoScript is set to "temporarily allow" the site, so it can recalculate for you as you enter checkmarks in the boxes.)
=> Learning exercise: Use the tool to make your own table of permissions in OOo Writer.

**Qqmike** · Jun 08, 2011, 01:15 PM

Re: Commands at Konsole: Beginners: 3 parts

Under Construction: Not ready until this line is removed.

(reserved space)

**Qqmike** · Jun 08, 2011, 01:16 PM

Re: Commands at Konsole: Beginners: 3 parts

Under Construction: Not ready until this line is removed.
(reserved space)

Announcement

Commands at Konsole: Beginners: 3 parts

Commands at Konsole: Beginners: 3 parts

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