Command

Commands Area

Command

Description and/or Example

daemons kill -9 PIDnumber

Kills the process PIDnumber that we want to (it stops running) kill -HUP PIDnumbe does the same. Kill -STOP PIDnumber Stopis until a new command the NumberPID process. Kill -CONT PIDnumber Resumes the numberPID process that we stopped before.

daemons killall processname

Kills processname.

daemons ps aux

Lists the aplications that are now running with his PID(Process IDentifier). ps aux | more Pauses between screens. Very useful to get information to kill a running process.

daemons top

Shows the processes sorted by CPU use on real time, also free RAM and used SWAP.

daemons xkill

Kills on X-windows the process that we select by clicking it with the mouse. It's the same as kill but on graphical mode. Hotkey: Ctrl+Alt+ESC

files

alias ls='ls --color=tty'

When you type ls you'll see color output but only if the output goes to screen (not a file) you could insert this line in ~/.bash_profile to always do it.

files

dd if=/dev/fd0 of=diskimagename

Makes a disk image and saves it on diskimagename file.

files

dd if=diskimagename of=/dev/fd0

Saves the diskimagename file to a floppy disk.

files

df

Shows free disk space.

files

du -c files

Shows the total size used by the files.

files

du -s directory

Shows the directory size.

files

echo $PATH

Shows the current path.

files

emacs filename

Edits the filename Ctrl+X Ctrl+S (save), Ctrl+X Ctrl+C (quit).

files

find /directory -name 'filename'

Searches from directory the specified filename.

files

for x in $(ls /directory) do echo $x done

A little bash script to loop on the files in a directory.

files

grep

Searches for a string on a file. cat file.txt | grep stringtolookfor

files

joe filename

Text editor.

files

less file

I'ts like a better more, allows to go up and down and doesn't load the all the entire file when you call it.

files

ln -s /mnt/cdrom/Mame/roms /usr/games/lib/xmame

Makes a soft link to the cdrom roms directory as if it was /usr/games/lib/xmame (xmame must not exist)

files

mke2fs /dev/hda2

Formats the second partition from the first hard disk using the Linux format (ext2).

files

more filename

Shows filename on screen (it's lik: type | more on msdos) .

files

mount /dev/hda1 /mnt/c -t vfat

Mounts fat32 partition.

files

pico filename

A basic text editor. Needs It's size in bytes is very low.

files

rm -rf directory

Deletes the directory and all the files within. No confirmation requiered.

files

sed

Changes a string for another one on a file (used with pipes).

files

sed 's/stringA/StringB/' filename Changes the first occurrence of stringA on filename > newfilename for stringB and saves it in newfilename.

files

sed 's/stringA/stringB/g' filename Changes all the occurrence of stringA on filename for > newfilename stringB and saves it in newfilename.

files

tail -f filename

Shows only the last lines of filename (good to follow on real-time log files).

files

tar -zcvf filename.tar.gz directory

Compresses in tarball the directory and all subdirectories into filename.tar.gz

files

tar -zxvf filename.tar.gz

Decompress filename.tar.gz

files

wc filename

Line count, word cound and byte count for the file.

files

whereis filename

Finds filename and says where it is using the internal data base, that must be updated. updatedb updates it.

files

zip -r targetfilename directory

Compress directory and all its folders on ficherodestino.zip

files

zip -r zipfilenameyouwant.zip desiredirectoryname

Compresses using zip the desiredirectoryname and all the subdirectories.

image

convert -resize 640x480 original.jpg modified.jpg

Converts image to 640x480

image

mplayer videoyouwant.avi -vo aa Plays the video on ascii art.

network /etc/network/interfaces

Edit this file to change IP on Debian

network ifconfig

Shows your IP also is used to configure your network card.

network ncftp

An improved ftp client for console

network netstat -lnp --ip

If you type it being root, will display current running daemons.

scp Copies the file vmlinux remote from the host network [email protected]:/boot/vmlin 192.168.201 via ssh to current directory. ux . network

wget -c --passive-ftp ftp://filename

network wget -c http://filename

Downloads the file or continues the download using FTP passive mode. Downloads the requested filename or continues the download if the connection was lost.

network wget -rl 4 http://domainname

Downloads the website and all files on it until level 4

sound

mpg123 -q /directory/*.mp3 &

Plays in background from the shell the .mp3 music files allocated on the directory.

system

/sbin/hdparm -d 1 /dev/hda

Sets using_dma bit to 1 to enable Ultra-DMA access to disk.

system

/sbin/hdparm -tT /dev/hda

Performs a timing benchmark on device reads.

system

/sbin/hdparm /dev/hda

Shows hard disk configuration parameters.

system

bash

sh Extension.

system

bc

Is a text mode calculator.

system

chs

C shell.

system

dpkg -i package.deb

Installs package.deb (Debian).

system

if [ -x /path/to/dnetc ]; then echo The file /etc/rc.d/rc.local is like autoexec.bat from ms"Starting Distributed.net dos and we cand add this lines on it. If it's not running, Client..." /path/to/dnetc -quiet fi will start dnetc application.

system

ksh

Korn shell, combines sh and csh.

system

last

Show list of last logged in users (reads /var/log/wtmp).

system

ltrace elfexecutable

Traces an elf executable program (nice hacking tool)

system

nohup scriptname &

Runs scriptname in background and keeps running even if you close the window shell.

system

pdksh

ksh Extension.

system

rpm -e rpmname

Uninstalls rpm previous isntalled package (the rpmname must be obtained from rpm -qa and without .rpm).

system

rpm -qa |grep ftp

List current installed ftp servers.

system

rpm -qpl package.rpm

Shows what files are on the package.

system

rpm -Uvh package.rpm

Upgrades an installed package with the new one or installs it.

system

setterm -blank 0

Turns off console blank screensaver (that is On by default), you can put it on /etc/rc.local

system

sh

Changes to bash shell (Unix standard).

system

shutdown -h now

Shutdowns the computer. The same as halt

system

shutdown -r now

Reboots the computer. The same as reboot.

system

strace -s 200 executable

Intercepts system calls which are received by a process -s 200 is for string size 200 (nice hacking tools)

sytem

rpm -qi rpmname

Querys about version, complete description and more info for the package.

time

at 7:00 cdplayd

Sets the computer to play the cd at 7:00.

time

atq

Lists the automatic programmed jobs.

time

atrm 8

Deletes automatic job number 8.

time

date

Shows system date and time.

time

date -s "04/25/05" +"%D"

Changes sytem date to April, 25th 2005 .

time

date -s "15:00:00" +"%T"

Changes system time to 15:00.

time

Edit this file to memorize a job: etc/crontab

Ex: 00 00 20 10 * echo 'The winter is here' >/dev/null (this last command is to not send a mail to root). On the next directories you could copy applications or scripts that will run every time period. /etc/cron.hourly/ /etc/cron.daily/ /etc/cron.wee

time

rdate -p ntp.nasa.gov

Shows the server date and time.

time

rdate -s ntp.nasa.gov

Synchronizes your time and date with the server.

time

time application

Runs the application and when it's finished shows the running time.

time

uptime

Shows the total time since the computer was turned on.

users

/usr/bin/gpasswd -a user group

Asign that user to that group.

users

chmod mode file

Changes the file permissions

users

chown user:group file

Changes the file user and group owner.

users

gpasswd -d user group

To remove users from a group. The same is to edit: /etc/group

users

groups username

Shows groups that username is on

users

id username

Shows user identification and groups where he is on.

users

su

You become root until type: exit.

users

su -

Becomes root and reads root user's environment.

users

usermod -G group1,group2 user Asign groups to a user.

X

setxkbmap

Try if your AltGr keys doesn't work on X mode.

X

switchdesk desktoptype

Changes the default desktop to anther (gnome, kde, wmaker, etc...).