Here are some commands for Linux :
COMMAND LIST :
ac – Print statistics about the time they have been connected users.
adduser – See useradd.
alias – Create shortcuts to commands, list current aliases.
apt- get – Tool actualizacón / remote installation packages in debian based systems.
arp – Lets get / manipulate the list of MAC / IP addresses that the system sees.
arping – Sends ARP REQUEST to other computers on the network.
arptables – Firewall functions similar to control iptables but arp protocol traffic.
at – Work program, commands, scripts for later execution.
atq – List scheduled jobs pending execution by the at command.
awk – Analysis and processing patterns in files and listings.
basename – Delete the path name of a file.
bc – Calculator and mathematical language, very powerful.
biosdecode – BIOS information.
blkid – Displays attributes of block devices (disks, usb, etc..) Such as LABEL and UUID, among others.
bzcat – Uncompress files using bzip compressed or packaged.
bzip – Compressor / decompressor files.
bzmore – View the archive contents or packaged using bzip.
lime – Displays a calendar.
cat – Displays the contents of files and concatenates files.
CD – Change directory.
cfdisk – Disk partitioning tool, mainly used on Debian systems.
chage – Change the information (expiration, revocation, etc.) of a user’s password.
chattr – Change extended attributes of files and directories
chfn – Change the information used in finger.
chgrp – Changes the group of a file (s) or folder (s).
chkconfig – Controls / query how services are running or not on startup.
chmod – Change the permissions of a file (s) or folder (s).
chown – Changes the owner of a file (s) or folder (s).
chpasswd – Upgrade passwords or passwords in batch mode. Passwords can update user groups.
chroot – Execute commands in a restricted shell root to a directory and its subdirectories.
chsh – Change your default shell or login shell.
cleanlinks – Cleans symlinks unrelated and also removes empty directories.
clear – Clean the terminal.
cmp – Compares two files byte by byte.
convertquota – Converts from old formats quota.group quota.user and new formats and aquota.group
cpio – Copy, create, and extract compressed files in different formats and between teams or locally.
crontab – Manage files and cron for root users.
curl – Allows you to download or transfer url’s.
cut – Removes sections (columns mainly) of each line of a file or files.
date – Displays / sets the date and time.
dc – Interactive Calculator.
dd – Convert and copy files and file systems.
ddate – Displays the date in calendar format jarring.
df – Displays space usage of hard drives or partitions.
diff – Search and show differences between files.
dig – Props for querying DNS servers.
dircolors – Color setup for ls.
dirs – Allows you to display, manipulate the list of directories used in the stack. (See popd and pushd)
dmesg – Displays messages system startup (boot).
dmidecode – List of computer hardware BIOS directly. (Also: lshw)
dosunix – Converts files from MS- DOS to Unix format / Linux.
du – Displays space usage of files and directories.
dump – Allows creation of backups for the file systems ext and ext.
ECHO – Prints a line of text, variables, or content to a file.
edquota – Manages disk quota control user and group.
egrep – It’s like the ‘grep- E’, to use regular expressions.
eject – Unmount and eject removable media such as CD- ROMs.
env – Run a program in a modified environment.
ethtool – Allows you to display or change values of a network card.
exit – Exits the current shell or terminal.
expect – Create sequences and dialogues with other interactive sessions programmed commands or scripts.
export – Exports the value of a variable.
exportfs – Maintains a list of file systems NFS type which have been exported.
expr – Mathematical expression evaluator.
factor – Find the primes of a given number.
fc – List, edit and reejecuta previously executed commands.
fdisk – Disk partitioning tool, common to almost all distros.
fgrep – It’s like ‘grep- F’ to use regular expressions in file searches and listings.
file – Determines the file type.
find – File search, multiple search options.
findfs – Find a filesystem by UUID or LABEL (label).
findsmb – List information about computers that respond to SMB packets. List a Windows network. (Part
finger – Displays information about the system users.
Fortune – Prints a random adage.
fping – Lets send ICMP packets (pings) to multiple computers on a network and determine if they are
alive or not.
free – Shows the used and free space of RAM and Swap.
fsck – Tool to verify / repair file systems.
fuser – Identify processes using files or connections (sockets).
gawk – Analysis and processing patterns in files and listings. (Gnu version)
gcc – C compiler and GNU C + +.
gedit – GNOME text editor.
gpasswd – Enables management of the file / etc / group
gpg – Tool generation encryption and security certificates (opengpg).
grep – Look for patterns of strings within files.
groupadd – Create a new group in the system.
groupdel – Deletes a group in the system.
groupmod – Modifies a group on the system.
groups – Prints the groups to which a user belongs.
gzip – Compresses / expands files.
halt – Turn off the computer.
hdparm – Sets and displays features on the hard drives.
head – Displays the first lines of a file.
help – Help on bash internal commands.
history – Displays the user’s command history.
host – Utility consulting DNS server host.
hostname – Displays the computer name.
htpasswd – Manage files of user / password for basic authentication of Apache.
hwclock – Displays / Sets the date / time changes or hardware. (Date / Time System to date)
id – Displays the UID (User ID) and GID (Group ID) of the user
ifconfig – Displays / Configures the system’s network interfaces.
ifstat – Small utility that allows to observe statistics of network interfaces in real time.
init – Initialization control ejecucción level.
insmod – Modules inserted in the kernel.
ipcalc – Perform simple calculations on IP addresses.
ipcount – Identifying ranges of network, IP’s calculation.
iptab – Displays an IP address table prefix according to CIDR
iptables – Firewall configuration tool for Linux.
iptraf – Network traffic analyzer in text mode.
iwconfig – Set up a wireless network card.
iwlist – Gets details of a wireless card.
jobs – Displays user jobs in suspension or background.
kate – KDE Text Editor.
kill – Terminates processes, more correctly sends signals to processes.
killall – End processes with the same name or group.
last – Displays information from past users logged.
lastb – Displays information from the previous failed attempts to login.
less – Displays the contents of an archive, searchable and movement back and forth.
ln – Create links (shortcuts) soft and hard files and directories.
locale – Specific information about the local environment variables.
locate – Indexes and searches files. Slocate safer to use.
losetup – Defines and controls devices such as ‘loop’.
lpq – Sample documents for printing in the print queue.
lpr – Add a document to the print queue.
ls – List files and directories.
lshw – List of computer hardware BIOS directly. (Also: dmidecode)
lsmod – Displays the status of the modules in the kernel.
lsof – Displays open files in ejecucción program, or a user, process, etc.
lspci – List PCI devices in the system.
lsusb – List system usb devices.
mail – Send and receive email.
man – Command displays the manual indicated.
mc – Handler archvivos with mouse support in text mode, not every distro I have.
mcedit – Mc text editor.
mdsum – Check (and creates) files with md signature certification.
mkdir – Create directories.
mkfs – Build a Linux file system.
mkpasswd – Password generator. (Software Package ‘expect’).
modinfo – Displays information about kernel modules.
modprobe – Tool to add / remove kernel modules.
more – Pager similar to but less funcioanal less as it comes forward and retocede.
mount – Monta storage partitions enabled devices listed.
mtools – Set of utilities to access DOS disks from Linux.
mv – Moves files and directories.
netstat – Network Utility showing connections, routing tables, interface statistics, etc..
nice – Run a program with a priority other than normal ejecucción.
nohup – Runs a program immune to hangups and without access to a terminal.
openssl – Control, management, security certificate generation.
partprobe – Tells the operating system to the changes mentioned in / etc / fstab
passwd – Changes the specified user’s password.
ping – Send an ECHO_REQUEST (echo request) to a computer on the network.
pkill – Send signals to processes based on their attributes.
popd – Removes entries (directories used) from the list of directories used in the stack. (See dirs and
pr – Format or convert text files for printing.
ps – Displays system processes or user or both.
pstree – Displays processes as a tree.
pushd – Adds entries (directories used) in the directory list (stack or stack). (See dirs and popd)
pwck – Check the integrity of the file / etc / passwd
pwconv – Add shadow protection or sets the file / etc / passwd.
quota – You can see the use of user fees.
quotacheck – Create, verify, manage disk quota systems
quotaoff – Deactivates disk quotas.
quotaon – Active control disk quotas for users and groups.
rdesktop – Open graphics terminals has? Ia Windows computers.
reboot – Restart the computer.
renice – Changes the priority of a process or program ejecucción.
repquota – Report use of disk quotas.
resolveip – Solve the ip or host domain indicated.
rev – Reverses the lines of a file.
rm – Deletes or removes files.
route – Displays / changes the IP routing table.
rpm – Program installation / update / removing packages, redhat based distros.
runlevel – Displays the current run level and previous system.
scp – Copy files between computers, part of the package openssh (encrypted communication
screen – Virtual terminal manager.
thirst – Editor online file filters and transforms.
service – Run / stop services manually.
set – Displays or sets the environment variables for the user actuual.
shasum – Check (and creates) files sha signature certification.
shopt – Enables or disables variables shell optional behavior.
shred – Delete files securely and unrecoverable.
shutdown – Turn off or restart your computer.
sort – Sort lines of files and playlists
ss – Props like netstat but basic socket set fast listings.
ssh – Secure remote login program, openssh package program (encrypted communication protocol).
startx – Log X.
his – Change the current user indicated.
sudo – Allows user runs indicate that root commands.
sync – Forza memory blocks to disk, update the super block.
tac – As cat shows and / or concatenated files in reverse.
tail – Displays the end of a file.
tailf – Synonym tail- f command, lets you see in real time the end of a file, ie as you type, useful for
tar – Tool packer / compressor files.
testparm – Check samba smb.conf file for errors or corrections.
time – Returns the time that you ran the command or program indicated.
top – Displays system processes interactively and continuously.
touch – Create empty files, change access dates and / or modification of files.
tput – Change values or terminal capabilities, based on terminfo.
traceroute – Prints the route network packets to the destination.
tty – Print the name of the terminal on which this.
tzselect – Set an area or zone.
umask – Set permissions mask when creating directories and files.
umount – Unmount file systems.
unalias – Removes alias command, created with the alias command.
uname – Displays system information.
uniq – Omits or reports on repeated lines in a file or listing.
units – Converter units from one system to another, supports dozens of metrics.
update – Upgrade Tool / remote installation package (used in redhat, centos).
uptime – Shows how long has turned on the computer.
urpme – Urpmi package program to uninstall or remove packages.
urpmi – Upgrade Tool / remote installation packages, rpm based distros (used in mandriva).
useradd – Add users.
userdel – Removes users.
usermod – Modifies user information.
users – Displays the user names of all users currently connected to the system.
vi – Display visual editor, text editor, you find in all Linux distros.
vim – Same as vi but improved.
visudo – Editor for the configuration file / etc / sudoers sudo.
vmstat – Provides information on virtual memory.
w – Shows who is connected to the system and you are doing.
wall – Send a message to all terminals.
warnquota – Configure / etc / warnquota.conf to complement messages for disk quotas.
wc – Account words, lines, characters from a file or listing.
wget – File Downloader from the Internet and not interactive.
whatis – Short description, in a line of a command or program.
whereis – Locate the binary, source and / or libraries, and documentation of a comado.
Which – Shows the full path of a command.
who – Shows who is connected to the system.
whoami – Displays the current user.
xhost – Access control for X sessions
xkill – Mata or ends to an X client, ie a graphics program.
yes – Prints a string repeatedly until terminated or killed the command.
yum – Upgrade Tool / remote installation packages, rpm based distros (used in fedora, redhat and
zcat – Unzip / sample files compressed with gunzip (identical to gunzip- c)
zenity – Displays various types of dialogues in X from a terminal.
zless – Displays the contents of compressed files.
zmore s – Displays the contents of compressed files.
More Commands :
list: list. It shows the contents of the folder we indicate later. For example. If we want to show us what’s in / etc:
# Ls / etc
If we do not interpret anything what we want to see is the contents of the folder where we are today:
To display all files and folders, including hidden:
To display the files and folders along with the rights you have, what occupies, etc:
If we wanted to display the files in the same way as before, but also showing the hidden:
change directory: change directory. We can use it with absolute or relative paths. On the whole we indicate absolute path from the root (/). For example, wherever we are, if we write in console …
# Cd / etc / apt … we take that folder directly.
# Cd / … send us to the root of the filesystem.
Relative paths are relative to something, and that something is the folder where we are now. For example if we are on / home and want to go to a temporary folder called within our personal folder.
# Cd tu_carpeta / temporal
We avoided the / home early because otherwise we introduce draws on the directory where you are.
What this does is it takes you directly to your personal folder and wherever we are, is really very practical, very simple and that not everyone knows.
————————————————– ————– mkdir
make directory: make directory. Create a folder with the name that you indicate. We may use absolute and relative paths. We can tell you the whole path that precedes the directory we want to create, or if we are in the folder that will contain just enough to put the name:
# Mkdir / home / your_account / cucumber
If we are in / home / your_account …
# Mkdir cucumber
remove: delete. Clears the file or folder that you indicate. As before you can enter the full path and file name. This from now we will ignore, I think it has become clear with the two previous commands.
To delete a file: # rm filename
To delete an empty folder: # rm foldername
To delete a folder containing files and / or other folders:
# Rm-r foldername
Other options: “-f” does not ask for confirmation to delete or “-v” shows what clears.
copy: copy. Copy the file indicated where you say. Here we can also play with routes for both the source file, as in the destination. You can also put the name you want to give the copy. For example, if we were in / etc/X11 and would like to make a backup of xorg.conf in our personal folder:
# Cp xorg.conf / home / tu_carpeta / xorg.conf.backup
move: move. Same as above, only instead of making a copy, directly drives the file as you indicate, can be other than the original:
# Mv / etc / pepino.html / home / tu_carpeta / ese_pepino.html
Another very practical use that can be given is to rename a file. Simply indicate the new name in the second argument with the same path first. In this example we assume that we are in the folder that contains:
# Mv pepino.html ese_pepino.html
find: find. Find the file or folder that you specify:
# Find /-name cucumber
The above command would look everywhere folders and files called cucumber. If we were confident that is located at / var eg it indicaríamos:
# Find / var-name cucumber
If we’re not sure of the name can indicate it with wildcards. Suppose we seek name contains “Pepi” in the same folder as before:
# Find / var-name * pepi *
You have other options. For example we can tell you find the files / folders over 1500 KB:
# Find /-size +1500
Or the files / folders containing the name “Pepi” and have less than 1000 KB:
# Find /-name *-size pepi * -1000
clear: clear. Clears the screen / console.
Process Status: status of processes. It shows us what we want to know about the processes running on your system. Each process is identified by a number called PID. If we place …
… Will show a listing of all processes, their PID to the left and to the right name. If you want more information:
# Ps aux
kill: kill. Eliminates the process we indicate with PID:
Sometimes the process does not “die” at all, but you can force the system to safely kill him as follows:
# Kill -9
super-user do: do as root. The user account in Ubuntu is relatively normal. Have administrator rights to half. I mean, it does, but every time you do something important and systemic risk, it must be done by the prefix “sudo” and then typing the password.
For example, something we have done many times in the tutorials is to make a backup of the xorg.conf file. It is located in the / etc/X11 and that any user can change or delete anything if you are not an administrator or have rights as such, thanks to sudo. So we always did:
# Sudo cp / etc/X11/xorg.conf / etc/X11/xorg.conf
Whenever we need to make a apt-get/aptitude update or install and actions of this kind, we have to put before the “sudo”.
password: password. This command can change the password for our account. First we asked the current password as a security measure. Then prompts you to enter twice the new password.
super-user: root. By “their” we loguearnos as root. After writing it will ask for the root password and we as administrator.
This command also allows you to login with a different account. For example, imagine we have another account, besides root and ours, called “guest”. To login as such would be sufficient to:
# His guest
and then enter the password for that account.
Thanks to the combination of these two commands you can change the root password (the super-user).
# Sudo passwd
manual: manual.’s another powerful commands in linux. Program or command is normally comes with a complete help file on their use and their arguments. When desconozcáis how it is used and what arguments have a command or application you only have to type in console:
# Man named
Sometimes the information you provide us man can become excessive. Almost all commands and applications accept the argument “- help” to display more summarized some help. For example with aptitude:
# Aptitude – help
EXPLORING THE FILE SYSTEM
The file system is a collection of files and the directory hierarchy of your system. Among the main directories are:
/ Bin stands for binaries or executables. It is home to most of the essential system. Most (if not all) of the files in / bin with an asterisk (*) appended to their names. This indicates that they are executable files.
The files in / dev are known as device drivers (device drivers) and are used to access system devices and resources such as hard drives, modems, memory, etc..
/ Etc contains a number of system configuration files. These include / etc / passwd (the user database), / etc / rc (system initialization scripts, etc.).
/ Sbin is used to store essential system that will use the same administrator
/ Home contains the users’ home directories. For example, / home / user is the user directory. On a newly installed system, there is no user in this directory.
/ Lib contains the shared library images. These files contain code that share many programs. Instead of each program containing its own copy of the shared routines, they are stored in a common place in / lib. This makes executable files smaller and saves space on disk.
proc is a “virtual file system”. Files that are stored in memory contains, not on disk. They refer to various processes running on the system, and allow you to get information about which programs and processes are running at any given time.
Many programs have a need to generate some information and store it in a temporary file. The location for these files is / tmp
/ Usr directory is very important. It contains a number of subdirectories in turn contain some of the most important and useful programs and configuration files used in the system.
The directories described above are essential for the system to be operational, but most of the things that are in / usr are optional for the system. Anyway, are those optional things that make the system useful and interesting.
/ Var contains directories that often change their size and tend to grow.