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[References] Master Linux Command Reference

Discussion in 'Open Source' started by Satissh S, Feb 28, 2006.

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  1. Satissh S

    Satissh S New Member

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    Master Linux Command Reference

    Ok, You've installed linux, Gr8! Here is a free cookie.
    But learning and using linux will be meaningfull with the knowledge of the following ESSENTIAL *nix commands and their PRACTICAL applications.IMHO Here are a few commands which we'll be using typically for routine work as well as system administration of linux. Of course this guide is meant to be no where near comprehensive that's why i request our friends to add new commands which they think will be ESSENTIAL and USEFUL. Thanks a lot!

    Addendums

    Addendum 1: bash cheatsheet
    Addendum 2: copypasting within terminal
    Now to the command reference,
    1 . Mount :
    Mount command is used to mount a filesystem. To mount a FS we use the mount command followed by mount point or device file name as shown here,
    the syntax is,
    Code:
    # mount something somewhere
    
    1.
    Code:
    mount /mnt/cdrom
    
    This commands mounts the device with a pre-defined mount point of /mnt/cdrom in FSTAB(/etc/fstab) which is the cdrom drive /dev/hdc or /dev/cdroms/cdrom0 which is a symlink to /dev/hdc by the way.

    2.
    Code:
    mount /dev/hdc /mnt/cdrom
    
    This command mounts the device /dev/hdc in /mnt/cdrom. The device needs to be specified if it's not pre-defined in FSTAB.

    Popular Parametres:-
    a. -t
    One of the most important param to mount command is -t which specifies the filesystem type,
    For example, if one wants to mount a ntfs FS
    Code:
    mount -t ntfs /dev/hda1 /mnt/win_c  
    
    This command mount the ntfs partition /dev/hda1 in /mnt/win_c
    You can specify different FS's such as reiserfs, fat32 etc along with -t . Msdos formatted floppies use 'msdos' filesystem. if you are unsure abt the partition use '-t auto' to try making the shell guess the mount point.

    b. -r
    The -r param helps you to mount stuff in a read-only filesystem or mount stuff as readonly.

    c. -w
    The -w param helps to mount the filesystem with write option. Special case for us is that knoppix livecd usually mounts the hdd's partitions as readonly as default. You use this option to mount partitons using write permission just in case you need to trouble shoot a boot loader config.

    d. -o loop
    The -o loop option parametre is used to mount ISO disk images to another directory and view the contents of the ISO.
    For example you want to view the contents of a D/L'ed ISO
    Code:
    mount ubuntu-breezy-5.10-i386.iso /mnt/image -o loop
    
    2. Umount :
    The umount command helps to unmount filesystems. You can invoke this with,
    Code:
    umount /dev/hda2 (device name) or 
    umount /mnt/win_c (directory mounted)
    
    Popular Parametres:-
    a. -f
    This -f parametre forcefully umounts a network filesystem or an unreachable filesystem.

    b. -l
    Force unmount the filesystem. We especially use this command when we come out of a chrooted partition and wan't to unmount that filesystem,(IME usual problem with knoppix) it would be busy. We can use lsof command to check which programs are accesing the filesystem and unmount it.

    3. fdformat :
    This command performs a low-level floppy disk format
    Code:
    fdformat /dev/fd0
    
    4. mkfs :
    Using the mkfs command you can create any supported filesystem on an accesible diskvolume. This is high-level formatting and data lost is lost forever.
    For example, if we wan't to create a windows boot floppy quickly, all you have to do is
    Code:
    mkdosfs /dev/fd0
    
    This command is also used to create filesystems on large partitions
    Code:
    mkreiserfs /dev/hda3
    mke2fs -j /dev/hda3
    mkswap /dev/hda3
    mke2fs /dev/hda3
    mkjfs /dev/hda3
    
    where /dev/hda3 being the targeted partition. There is another way to do the above however,
    Code:
    mkfs -t reiserfs /dev/hda3
    
    does the same job as well.

    5. cp :
    As the name suggests, copies files from here to there.
    Code:
    cp $LINUX/i386/boot/bzimage /boot/bzimage
    
    copies the file bzimage from one folder to another.

    Popular parametres:-
    a. -a
    The -a parametre is used to archive a directory to another location, maybe as a backup also i saves file permissions and symbolic links status. Used for backing up file WITH permissions, so that you can replace if something gets screwed up.

    b. -b
    Ths -b param instructs the cp to make backup of any file with the same name in the destination directory as the copyied file so that the command doesn't explicitly ask you to what to do.

    c. -f
    This param instructs the command to forcefully replace any exixting file with the same name as the copyied file.

    d. -r
    Copies files and folders again and again recursively.

    e. -i
    Asks for confirmation b4 replacing any existing file.

    6. mv :
    As the name suggests moves files from here to there and as the name doesn't suggest it also renames files.
    Code:
    mv /home/user/file1 /home/user/files/file1 <moves file1 >
    mv /home/user/file1 /home/user/file2 <renames file1 to file2>
    
    The parametres for cp also apply to mv.

    7. rm :
    This command coressponds to delete
    Code:
    rm /home/user/garbage1 <where garbage1 is the deleted file>
    
    for directories however,
    Code:
    rm -R /home/luser <where /home/luser is the deleted directory>
    
    A similar command is rmdir
    Always re-check a rm command because a file rm'ed is pretty much deleted. The params of cp and mv also applies to rm.

    8. ln :
    There are two types of links, hardlinks and symbolic links. Hardlinks refer to link for the same file with two or more directory entry. That is say a file called file1 resides at /home/user and we create a link for this file1 to /home/user/files/file1 then the file resides on both and is deleted only when both the references are deleted. Symbolic links are softlinks that refer to the file, like a pointer from another location. We can use ln or cp command to create hard as well as symbolic links. We use
    cp -l to create hard links and cp -s to create symbolic links. However my favourite method is ln.
    Code:
    ln /home/user/file1 /home/user/files/file1 <hard link>
    ln -s /home/user/file1 /home/user/files/link1 <symbolic link>
    
    Application:
    If you get hold of software binaries, you can simply copy the directory to a conventional location, say for azureus to /opt and create a symlink pointing to /usr/bin so that you need not cd into the azureus directory and start it with ./azureus.
    Code:
    ln -s /opt/azureus/azureus /usr/bin/azureus
    
    Now you can type azureus in run dialog to run azureus.

    9. ls :
    Using ls to view the file contents is one of the fun parts of linux, practically when ls is combined with switches and sequences you don't even need a graphical file manager.
    The following ls command is used to view the contents of the folder with permissions.
    Code:
    ls -l
    
    use ls with ordinarily to view the folder contents is quite efficien for small folders but when you want to view the particular files starting with x we add the following sequence.
    Code:
    ls /etc/X11/x*
    
    this command will list all the files in /etc/X11/ directory starting with 'x'.
    Using [tab] autocompletion along with these neat tricks makes bash one of the most favourite shells for users.

    10 cd :
    Change into a directory from another directory.
    Code:
    cd /usr/local
    
    changes the current working directory to /usr/local.
    you can use pwd to view the current working directory.

    11 mkdir :
    Create a new directory within the current directory or another directory anywhere else.
    Code:
    mkdir shared (make a directory shared within the current /usr/local directory)
    mkdir /usr/local/bin (make a directory bin within /usr/local)
    
    12 chmod :
    Change the permissions to files or directories.
    To check permissions of a 'new' directory you can use the following command
    Code:
    ls -ld new
    drwxr-xr-x <owner> <group> <modified time>
    
    this specifies the permissions as
    {file-type} {owner} {group} {others}
    <directory><read-write-execute> <read-xxx-execute> <read-xxx-execute>
    to change em'
    Code:
    chmod 700 new
    
    Permissions cheat sheet:
    changes the permissions to rwx------ meaning no access to group as well as others and full access to the owner.
    There are several numbers denoting file permissions as modes. The popular is 700 which gives full access to the owner.
    Popular Parametres:
    A most used parametre is -r to recursively change permissions to direcotries and files within them. for example,
    Code:
    chmod 700 -r new
    
    changes permissions to all files and folders within new to 700

    13. chown :
    Change the ownership to files or directories
    to change the owner for a 'new' file or folder to a new owner.
    Code:
    chown user1 new
    
    changes the ownership of new to user1.
    Normally we use the this command recursively with -r option to change recursively the ownership of directories.
    Code:
    chown -r user1 new
    
    A similar command is chgrp which changes the group similarly.

    14. df -h :
    The df command is used to view info abt all mounted partitions.
    Use df -h to find the used and free space of your hard disk volumes.
    Code:
    df -h
    
    It will display as output, like for example
    Code:
    Filesystem            Size  Used Avail Use% Mounted on
    /dev/hda4             7.1G  4.5G  2.6G  64% /
    udev                  505M  168K  505M   1% /dev
    /dev/hda1              21G   18G  2.5G  88% /home
    /dev/hda2             9.9G  2.3G  7.1G  25% /backup
    /dev/hda3             266M   16M  237M   7% /boot
    none                  505M     0  505M   0% /dev/shm
    
    15. pciutils :
    Pciutils are a set of utils to make the life of a *Nix system admin easier
    1. lspci:
    View your pci devices. This displays all the devices connected via pci. Normally we either use grep to search the output and display the ones we want.
    For example,
    Code:
    lspci | grep VGA <outputs your VGA device>
    01:00.0 VGA compatible controller: nVidia Corporation NV40 [GeForce 6800 GT] (rev a1)
    
    similarly,
    Code:
    lspci | grep audio <outputs your audio device>
    00:1f.5 Multimedia audio controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) AC'97 Audio Controller (rev 02)
    
    Or, you can pipe the entire thing view it using more or less, or you can save it as a log and view using your editor.
    Code:
    lspci | more
    lspci >> log
    
    2. lsmod :
    Displays the loaded modules,
    Code:
    lsmod
    Module                  Size  Used by
    snd_intel8x0           30944  0
    snd_ac97_codec         91900  1 snd_intel8x0
    snd_ac97_bus            2944  1 snd_ac97_codec
    nvidia               4086128  12
    
    You can pipe them out similarly.

    3. lsusb :
    Displays the CONNECTED usb devices.
    Code:
    lsusb
    Bus 005 Device 001: ID 0000:0000
    Bus 004 Device 001: ID 0000:0000
    Bus 003 Device 001: ID 0000:0000
    Bus 002 Device 001: ID 0000:0000
    Bus 001 Device 001: ID 0000:0000
    
    4. lsof :
    This program displays informations on open files, used devices etc.,
    Code:
    lsof | grep /mnt/cdrom
    
    Use this command to see if a umount fails with device busy quote.

    5. dmesg :
    Displays the kernel output messages while boot time.
    Code:
    dmesg | less
    
    The same can be used with | or >> to save.

    16. du :
    The du command displays the disk usage by partition by partition basis. For example,
    Code:
    du /usr <displays how much space each directory in /usr is consuming>
    
    Don't use this command without this --max-depth=n option or you'll find your self having to wait a while ;) This option limits du to n directory depth.
    For example,
    Code:
    du --max-depth=1 /opt <outputs>
    11283   /opt/xpde
    12      /opt/libreadline-java
    10432   /opt/eclipse-extensions-3.1
    10789   /opt/opera
    15397   /opt/RealPlayer
    89309   /opt/blackdown-jdk-1.4.2.03
    5511    /opt/eclipse-extensions-2
    10927   /opt/eclipse-extensions-3
    21928   /opt/firefox
    28961   /opt/thunderbird
    20278   /opt/sunbird
    1248    /opt/netscape
    72972   /opt/sun-jre-bin-1.5.0.06
    55232   /opt/blackdown-jre-1.4.2.03
    400     /opt/blackdown-java3d-bin
    354677  /opt
    
    Again you can pipe out the output if you can view it in the terminal.

    17. stat :
    This command displays information about files like ls -ld with permissions, ownership etc.,
    But with several other tasty stuff.
    Code:
    stat /opt <outputs>
    File: `/opt'
      Size: 568             Blocks: 1          IO Block: 131072 directory
    Device: 304h/772d       Inode: 108         Links: 17
    Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
    Access: 2006-02-12 13:06:18.000000000 +0530
    Modify: 2006-02-28 05:03:43.000000000 +0530
    Change: 2006-02-28 05:03:43.000000000 +0530
    
    18. uptime :
    This command returns the uptime of the system. useful for knowing uptime of servers.
    Code:
    uptime <outputs>
    20:50:00 up  2:10,  4 users,  load average: 0.00, 0.00, 0.00
    
    19. free :
    This command lists the memory usage of the system.
    Code:
    free <outputs>
                total       used       free     shared    buffers     cached
    Mem:       1032792     447436     585356          0      79380     140872
    -/+ buffers/cache:     227184     805608
    Swap:            0          0          0
    
    20. who and finger :
    the commands who and finger provide information abt users logged in to the system.
    Code:
    who <outputs>
    sathya   :0           2006-02-28 18:40
    sathya   pts/0        2006-02-28 18:40
    sathya   pts/1        2006-02-28 18:56
    sathya   pts/2        2006-02-28 19:55
    
    Code:
    finger <outputs>
    Login     Name       Tty      Idle  Login Time   Office     Office Phone
    sathya              *:0             Feb 28 18:40
    sathya               pts/0    2:11  Feb 28 18:40
    sathya              *pts/1    1:10  Feb 28 18:56
    sathya              *pts/2          Feb 28 19:55
    
    As you can see finger provides some additional information.

    21. top :
    This is such an essential command which is very hard to ignore. This is more of a utility than a command
    Code:
    top <outputs>
    top - 20:56:16 up  2:16,  4 users,  load average: 0.00, 0.00, 0.00
    Tasks:  83 total,   1 running,  82 sleeping,   0 stopped,   0 zombie
    Cpu(s):  0.0% us,  0.0% sy,  0.0% ni, 100.0% id,  0.0% wa,  0.0% hi,  0.0% si
    Mem:   1032792k total,   447580k used,   585212k free,    79624k buffers
    Swap:        0k total,        0k used,        0k free,   141036k cached
    < c o m m a n d l i n e  to execute stuff within top ----------------->
      PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
     5616 root      16   0 60820  49m 3844 S    0  4.9   1:31.47 X
        1 root      16   0  1460  516  448 S    0  0.0   0:00.69 init
        2 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/0
        3 root      34  19     0    0    0 S    0  0.0   0:00.00 ksoftirqd/0
        4 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/1
        5 root      34  19     0    0    0 S    0  0.0   0:00.00 ksoftirqd/1
        6 root      10  -5     0    0    0 S    0  0.0   0:00.09 events/0
        7 root      10  -5     0    0    0 S    0  0.0   0:00.00 events/1
        8 root      10  -5     0    0    0 S    0  0.0   0:00.00 khelper
        9 root      11  -5     0    0    0 S    0  0.0   0:00.00 kthread
       12 root      10  -5     0    0    0 S    0  0.0   0:00.00 kacpid
       86 root      10  -5     0    0    0 S    0  0.0   0:00.01 kblockd/0
       87 root      10  -5     0    0    0 S    0  0.0   0:00.00 kblockd/1
       90 root      10  -5     0    0    0 S    0  0.0   0:00.00 khubd
      182 root      20   0     0    0    0 S    0  0.0   0:00.00 pdflush
      183 root      15   0     0    0    0 S    0  0.0   0:00.04 pdflush
    
    Notice the command line, there we execute severel commands for working with processes.
    As you can see x consumes a lot of memory and is displayed in the top.
    Commands:
    Top Cheat sheet:
    22. Process manipulation :
    ps and pstree commands are used to deal with processes. ps outputs processes info and pstree outputs tree like info structure.

    1. ps
    Code:
    ps <outputs>
     PID TTY          TIME CMD
     6030 pts/2    00:00:00 su
     6033 pts/2    00:00:00 bash
     6156 pts/2    00:00:00 ps
    
    2. pstree
    Code:
    pstree <outputs>
    initacpid
         6*[agetty]
         cron
         dbus-daemon
         dbus-launch
         dcopserver
         events/0
         events/1
         gam_server
         gconfd-2
         gdmgdmX
                    startkdekwrapper
                               ssh-agent
         gpm
         2*[jfsCommit]
         jfsIO
         jfsSync
         kaccess
         kded
         kdeinitartsd
                  kio_file
                  klauncher
                  konqueror
                  konsolebashemacs
                  konsolebashsubashpstree
                  kwin
                  mozilla-launchefirefox-bin2*[{firefox-bin}]
         kdesktop
         khelper
         khpsbpkt
         kicker
         kio_uiserver
         kirqd
         klipper
         knotify
         korgac
         ksmserver
         ksoftirqd/0
         ksoftirqd/1
         kswapd0
         kthreadaio/0
                  aio/1
                  ata/0
                  ata/1
                  kacpid
                  kblockd/0
                  kblockd/1
                  khubd
                  kseriod
                  2*[pdflush]
                  reiserfs/0
                  reiserfs/1
                  xfsbufd
                  xfsdatad/0
                  xfsdatad/1
                  xfslogd/0
                  xfslogd/1
         migration/0
         migration/1
         sshd
         syslog-ng
         udevd
         xinetd
    
    as you can see pstree displays the initiated process with the root process, all providing us tasty info.

    3. nice and renice
    nice and renice commands are used to start a process and set process with different priorities.
    Code:
     
    nice <option> <command>
    
    renice
    Code:
    renice -2 -p [i]nnnnn[/i]
    
    the above command changes the priority of process with ID nnnnn to -2. giving it precedence over others.

    4. kill
    This kill command is used to kill a process with a -s signal and process id.
    Code:
    kill -l (use this to display the list of signals)
    kill -s [i]signal[/i] pid[...]
    
    23. grep :
    Search and limit output using grep
    The grep command is used to search and limit the output, like we did when using lspci utilities.
    For example, if you want to view screen information for your screens in XORG.Conf(/etc/X11/xorg.conf)
    Code:
    more /etc/X11/xorg.conf | grep Screen <outputs>
    Screen      0  "Screen0" 0 0
    Section "Screen"
            Identifier "Screen0"
    
    24. slocate :
    Use this security enhanced version of locate to get files and folders info.
    First you need to create a directory index
    Code:
    slocate -u
    
    This wud take sometime to finish.
    then search for files
    For example,
    Code:
    slocate xorg.conf <outputs >
    /etc/X11/xorg.conf.example
    /etc/X11/xorg.conf
    /usr/share/man/man5/xorg.conf.5x.gz
    /usr/portage/app-emulation/vmware-linux-tools/files/4.5.2/xorg.conf
    /usr/portage/app-emulation/vmware-linux-tools/files/5.0.0/xorg.conf
    
    25. echo :
    The command echo is used to print stuff in the standard output.
    for example,
    Code:
    echo hello world <outputs>
    hello world
    
    However, its most useful use is you can redirect it to file.
    for example,
    Code:
    echo \
    > GENTOO_MIRRORS="http://mirror.phy.olemiss.edu/mirror/gentoo"\
    > >> /etc/make.conf
    
    The above commands add the line GENTOO_MIRRORS="http://mirror.phy.olemiss.edu/mirror/gentoo" to /etc/make.conf.
    But watchout though! i ended up totally cleaning my /etc/make.conf by using >param which deletes the contents of the file and adds the echoed stuff. So always make sure you use >> .

    So that ends things up., but let this thread be used by all of us to add the commands that we think will be useful for a new linux user to learn and implement. Lets start linuxing, shall we?

    Credits :
    1. Linus, RMS and friends for creating this awesome OS.
    2. All programmers, coders and hackers.
    3. Esr and friends of 'OpenSource' movement.
    4. All MAN page and document writers of those excelent projects.

    License :
    This document and its derivatives are licenced under the GNU free document license. (any version)
    www.gnu.org

    Request :
    To err is human, Please point out any errors, typos in commands in the document, thanks. If you notice any italics tags within code, please notify me. Thanks.

    Edit History:
    Last edited at 25-6-2006 21:18 pm, edited four times in total.
    => A minor mistake corrected.
    => Altered document in accordance with changing times.
     
    Last edited: Jun 25, 2006
  2. nach p

    nach p New Member

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    Nice Thread .Surely help a lot For Newbies like me and also to otheres to venture into GNU/Linux. :) :)
     
  3. desertwind

    desertwind New Member

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    Nice tut there Satya.

    I'll add to it later, when I get time.
     
  4. vignesh

    vignesh New Member

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    Great post there Satissh....
     
  5. mediator

    mediator New Member

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    Real nice post...I hope this will be made sticky!
     
  6. OP
    OP
    Satissh S

    Satissh S New Member

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    Here are a few more,

    26. tar :
    This is a very essential command in a way that it compresses and decompresses files. There are a lot of options to this command and it's difficult to list everything here, so i will list the one which most linux users will most probably use and their functions as well as where to use them. For more read man tar This tar command actually calls seperate commands for seperate file type, for example to compress a .tar.bz2 it calls bzip2 command.
    Usually, you get the following compressed archive .tar.bz2, .tar.gz, .tgz.
    Use the c option to create an archive and x option to extract from an archive.
    Options Cheetsheet
    Common Uses
    1. To extract a bzip2 file,
    Code:
    tar xkvjpf file.tar.bz2
    
    2. To extract a gz file,
    Code:
    tar kxvzf file.tar.gz
    
    3. To archive files,
    Code:
    tar cvjfp yumbackup.tar.bz2 /var/cache/yum
    as you can see, this backs-up all your yum downloads in to bzip2 format which has a better compression than gz.
    
    27. mkisofs :
    You dont need k3b to burn cd's in linux. For command line junkies, here is how you can burn using commandline. The mkisofs command creates an iso file that you can burn using cdrecord. This command has a lot of options, but i'll list only the main ones here. So you can use man mkisofs to learn more.
    Basic usage for creating an iso is,
    Code:
    mkisofs -r -J -T -o /backup/backup.iso /home
    
    as you can see this command creates a backup.iso in the current directory which creates a backup of /home.
    Options Cheatsheet
    28. cdrecord :
    This command is used to burn the cd we created using mkisofs. As with any linux app, this has a lot of options but i'll be reviewing only the most useful ones here.
    Code:
    cdrecord -v -tao speed=40 dev=/dev/hdx /backup/backup.iso
    
    as you can see, this command burns the backup.iso we created to the empty cd in /dev/hdx with the following options.
    cdrecord cheetsheet
    You can also use -multi to enable multisession mode. This needs to be used for all subsequent sessions.

    PS: I request the friends here in the digit opensource community to continue in the command number so that we can use the command number as a reference when giving to new users. Thanks :)

    Edit History :
    Corrected a minor mistake. ;)
     
  7. Ramakrishnan

    Ramakrishnan The Researcher

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    Wow, what a post
     
  8. vignesh

    vignesh New Member

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    Here .. the du command can also be used with the -s option to just get the total size of a directory without displaying the size of each file..

    Code:
    du -s ./
    ways to get to your home directory

    Code:
    cd 
    
    cd ~ 
     
    cd /home/user
    
    cd $HOME
    
    directory..

    . points to current directory

    .. previous directory


    Info about yourself...

    id to see your username,group(primary and secondary)

    echo $USER to print your username

    groups

    The groups you belong to..

    set list all the variables that can be set in the shell and enviroment

    env to see environment variables only

    you can set them just type the variable name= new value

    Personalize your system....

    /etc/issue Message at login prompt

    /etc/motd Message of the day, message that will be displayed after you login

    alias set an alias to a command that you find easy to remember...

    Code:
    alias c='clear'
    alias bye='logout'
    
    add your aliases to your. .bashrc file so they are permanent.

    to unset an alias for the current session use the unalias option.

    change your prompt...

    Code:
    
    PS1='[\u in \w]' add this also to .bashrc if you want to be permanent
    
    
    cheat codes

    /u username
    /t time
    /w working dir
    /W full path
    /h hostname


    @Satissh

    The tar command can be also like this without so many parameters

    tar cvf file.tar file Create a tar

    tar jcvf file.tar file Create a tar and compress it with bzip2

    tar zcvf file.tar file Create a tar and compress it with gzip

    tar xvf file.tar To extract

    with bzip2 tar xjvf file.tar.bz2

    with gzip tar zxvf file.tar.gz

    I am a vi fan ...so will compile a list of shortcuts and then paste it...Since I am on dialup I can`t type it all now... :D
     
  9. OP
    OP
    Satissh S

    Satissh S New Member

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    A few more :)

    29. Chroot :
    The chroot command, 'change root' changes your root directory to the directory specified. For a temporary sesion, you can type exit to come out of it. We usually do this to repair a broken install or repair some mal-functioning in the system.

    where, the /xxx/xxx is the directory you want to make your temporary root directory.

    Chrooting the world:
    To chroot to your system, from within a live-cd,
    1. Mount all the partitions.
    2. Enable swap if you have one.
    3. Mount the proc filesystem after mounting the root, this is important!!
    Code:
    mount -t proc none $PATH/proc
    where $PATH is the path to where root partition is mounted.
    4. Now execute,
    Code:
    chroot $PATH /bin/bash

    30. Rmdir:

    The rmdir is a command to delete a directory, similar to rm command but it deletes the directory only. So if you try to delete a directory with rmdir that has files you'll get an error that the opeartion can't be performed. So rm -r is more effective.
    anyways,

    will delete the directory unlucky in your home directory.
     
    Last edited: Jun 25, 2006
    nach p likes this.
  10. JGuru

    JGuru Well-Known Member

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    Great Job Satish. I think you can add a few more there to make it a one stop
    reference. Including Copying, moving files ( using Terminal Window), chown,
    Some administration commands, the basic commands etc., That will help the
    users migrating from Windows to Linux.
     
  11. OP
    OP
    Satissh S

    Satissh S New Member

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    Well, i've added those in the first post, command number 5,6,8,12,13 :)
    We'd love if this was a wiki wont we?? , we can edit easily, make up for navigation. etc.,
     
  12. chesss

    chesss mera kutch nahi ho sakta

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    Thanks there, this post was very useful for me :)
     
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