Beberapa Command dasar LInux

mau belajaran linux nih… mumpung ada alatnya… jadi tadi sempet cari2 di google… nemu deh command linux paling dasar..

sementara masih pake bahasa inggris, nanti di edit atu atu… biar rada familiar ma orang indo gitu :D…

ok langsung COPas Aja.

Getting Help

man – Look at manual page, do this to see almost any command’s options – example: “man ls” – DO THIS WITH MOST OF THESE COMMANDS!!!

Listing and Moving Files and Directories

ls – LiSt files – “-a” lists all files, “-l” give a long DOS-dir-like output – example: “ls -la”

cp – CoPy – copy file(s) from one location to another – example: “cp *.c another_directory/”

mv – MoVe – move file(s) from one location to another, same as cp except it removes files afterwards

rm – ReMove – delete files – example: “rm *.o”

cd – Change Directory – example “cd /tmp”

mkdir, rmdir – MaKe DIRectory and ReMove DIRectory

ln – LiNk – make a link to a file – two types of links, normal and symbolic – example: “ln -s original newlink”

Special Directories – ‘.’ is current, ‘..’ is current’s parent, ‘~’ is home, and ‘/’ is the root (or top) of all directories

Redirection and Shell Stuff

| – Pipe, one of UNIX’s best features, used to send output from one program to be input to another – example: “ls -l | grep uzi”

>, >>, < – Redirect output of a program to a file, append output to end of a file, and get input from a file – example: “./a.out < input > ouput”

*, ? – Wildcards – used to specify any number (including zero) of any character for ‘*’, and any one character for ‘?’ – example: “ls *.?”

$var – An environment variable, where “var” is the name and a value can be seen using “echo $var”

set, setenv – used to set environment varibles, depending on shells.

Managing File Permissions

Sample “ls -l /bin/ls” output: -rwxr-xr-x 1 root root 29980 Apr 23 1998 /bin/ls
– First ten characters are the file’s permissions. First is file type, ‘-‘ for normal, ‘d’ for directory, ‘l’ for symlink, etc.
– Three sets of three characters of “rwx”, or Read, Write, Execute permission – first for owner, then group owner, then everyone.
– Then we have number of links to file, owner of the file, group owner of file, file size, date it was last modified, and the file’s name.

chmod – Change a file’s mode or permissions – one way is to use octal numbering – example: “chmod 751 /bin/ls” for rwxr-x–x

chgrp – Change a file’s group – example: “chgrp users /bin/ls”

chown – Change a file’s owner – example: “chown uzi /bin/ls”

umask – Set default file permissions (generally, do the opposite, or “777 minus what you want”)

Process Management

ps – Get a listing of running “processes” or programs – example: “ps -aux”

kill – Kill a running process – example: “kill -CODE PID”, where CODE is an optional kill code, and PID is the process ID #.

& – Run a program in the background – example “netscape &”

CTRL-Z – Suspend a running program

CTRL-C – Kill a running program

fg, bg – Put a suspended program in the foreground or background

jobs – List running programs of this terminal – each has a number that can be refered to as %#, or %1 for number one (useful with fg, bg and kill)

nice – Make a program use less computer time

nohup – Let a program run after you log out (NO Hang-UP)

Viewing Text Files

cat – Concatinate and display files, used to output a file’s contents without pausing – example: “cat textfile”

more – Like cat, but pauses every screen-full – example: “more prog.c”

less – Like more, but more powerful

head, tail – View the beginning or ending of a file, given a number option with display that many lines – example: “tail -25 /var/spool/mail/uzi”

wc – Get statistics of how many lines, words and characters in a file – example: “wc file.txt”

Searching and Comparing

find – Find a file, second argument is where to search from – example: “find . -name ‘*.c’ -print”

grep – Look for text in a file – example: “grep variable *.c”

cmp – Compare two files – example: “cmp file1 file2”

diff – Output difference between two files – example: “diff prog.c.orig prog.c > prog.c.diff”

Printing – Depending on which Unix you’re using (BSD type, SYSV type) is which you may be using

lpr, lp – Print a file -examples: “lpr -P printer file” or “lp -d printer file”

lpq, lpstat – Get statistics on a printer(s)

lprm, cancel – Cancel a print job

Finding and Communicating with other Users

finger – Get information on another user on the system – example: “finger uzi”

w, who – Find out who else is on a system

write – Write a message to a user (user CTRL-D to stop) – example: “write uzi”

talk – Talk to a user (CTRL-C to stop, and there’s also “ytalk” which is an enhanced version) – example: “talk uzi”

mesg – Use “mesg y” or “mesg n” to allow or disallow others to write and talk to you

Remote Commands

telnet – Open a connection on another system – example: “telnet”

ftp – Retrieve files with the File Transfer Protocol – example: “ftp”

rlogin – Similar to telnet, but if you have a “.rhosts” file with allowed machines, you can log in without a password

rsh – Also using “.rhosts”, lets you run one command on another machine without logging in

rcp – Another that uses “.rhosts” and lets you copy files from another machine


alias – Aliases can be used to make a shortcut for a common command – example: “alias dir ‘ls -l'” or “alias dir=’ls -l'”, depending on shell

at – Lets you have a program run “at” a certain time

crontab – Schedule regular programs to run at certain times (some let all users have their own crontab file)

cal – Print a calendar for a given month – example: “cal 8 1976” or just “cal” for this month

date – Print current time and date

df – Find out how much free disk space is available – example: “df -k .” for current directory in kilobytes

du – Find out disk usage of a file or directory – example: “du -ks ~” for size of your entire home directory

echo – Repeats or echoes the argument – example: “echo hello” prints “hello”

tar – Tape ARchive – allows you to pack many files together – example: “tar -xvf file.tar” to extract

gzip, gunzip – Compress or uncompress *.gz files – example: “gzip file.tar”

passwd – Change your password on a system

spell – Spellcheck a text file against system dictionary – example: “spell paper.txt”

sort – Sort contents of a file

time – Get runtime of a program – example: “time ls -l”

uname – Get info on a machine – example: “uname -a”

uptime – Get how long a machine has been up

which, whence, where – File out which program you’ll be running, or where all occurences of a program is in your path – example: “which ls”

vi, pico, emacs, jed, joe – Text editors

pine, elm, mutt, mailx, mail – Email programs