Friday, September 7, 2007

Linux BASH

alias  Create an alias
apropos  Search Help manual pages (man -k)
awk  Find and Replace text, database sort/validate/index
break  Exit from a loop
builtin  Run a shell builtin
bzip2  Compress or decompress named file(s)

cal  Display a calendar
case  Conditionally perform a command
cat  Display the contents of a file
cd   Change Directory
cfdisk Partition table manipulator for Linux
chgrp  Change group ownership
chmod  Change access permissions
chown  Change file owner and group
chroot Run a command with a different root directory
cksum  Print CRC checksum and byte counts
clear  Clear terminal screen
cmp  Compare two files
comm  Compare two sorted files line by line
command  Run a command - ignoring shell functions
continue  Resume the next iteration of a loop
cp Copy one or more files to another location
cron  Daemon to execute scheduled commands
crontab  Schedule a command to run at a later time
csplit Split a file into context-determined pieces
cut Divide a file into several parts

date  Display or change the date & time
dc  Desk Calculator
dd  Data Dump - Convert and copy a file
declare  Declare variables and give them attributes
df Display free disk space
diff  Display the differences between two files
diff3  Show differences among three files
dig DNS lookup
dir Briefly list directory contents
dircolors  Colour setup for `ls'
dirname  Convert a full pathname to just a path
dirs  Display list of remembered directories
du  Estimate file space usage

echo  Display message on screen
egrep  Search file(s) for lines that match an extended expression
eject  Eject removable media
enable Enable and disable builtin shell commands
env  Environment variables
ethtool  Ethernet card settings
eval  Evaluate several commands/arguments
exec  Execute a command
exit  Exit the shell
expand Convert tabs to spaces
export Set an environment variable
expr  Evaluate expressions

false  Do nothing, unsuccessfully
fdformat  Low-level format a floppy disk
fdisk  Partition table manipulator for Linux
fgrep  Search file(s) for lines that match a fixed string
file  Determine file type
find  Search for files that meet a desired criteria
fmt  Reformat paragraph text
fold  Wrap text to fit a specified width.
for  Expand words, and execute commands
format Format disks or tapes
free  Display memory usage
fsck  File system consistency check and repair
ftp  File Transfer Protocol
function  Define Function Macros

gawk  Find and Replace text within file(s)
getopts  Parse positional parameters
grep  Search file(s) for lines that match a given pattern
groups Print group names a user is in
gzip  Compress or decompress named file(s)

hash  Remember the full pathname of a name argument
head  Output the first part of file(s)
history  Command History
hostname  Print or set system name

id Print user and group id's
if Conditionally perform a command
ifconfig  Configure a network interface
import Capture an X server screen and save the image to file
install  Copy files and set attributes

join  Join lines on a common field

kill  Stop a process from running

less  Display output one screen at a time
let Perform arithmetic on shell variables
ln  Make links between files
local  Create variables
locate Find files
logname  Print current login name
logout Exit a login shell
look  Display lines beginning with a given string
lpc Line printer control program
lpr Off line print
lprint Print a file
lprintd  Abort a print job
lprintq  List the print queue
lprm  Remove jobs from the print queue
ls List information about file(s)
lsof List open files

make  Recompile a group of programs
man  Help manual
mkdir  Create new folder(s)
mkfifo Make FIFOs (named pipes)
mkisofs  Create an hybrid ISO9660/JOLIET/HFS filesystem
mknod  Make block or character special files
more  Display output one screen at a time
mount  Mount a file system
mtools Manipulate MS-DOS files
mv  Move or rename files or directories

netstat  Networking information
nice  Set the priority of a command or job
nl Number lines and write files
nohup  Run a command immune to hangups
nslookup  Query Internet name servers interactively

passwd Modify a user password
paste  Merge lines of files
pathchk  Check file name portability
ping  Test a network connection
popd  Restore the previous value of the current directory
pr Prepare files for printing
printcap  Printer capability database
printenv  Print environment variables
printf Format and print data
ps Process status
pushd  Save and then change the current directory
pwd Print Working Directory

quota Display disk usage and limits
quotacheck  Scan a file system for disk usage
quotactl  Set disk quotas

ram ram disk device
rcp Copy files between two machines.
read  read a line from standard input
readonly  Mark variables/functions as readonly
remsync  Synchronize remote files via email
return Exit a shell function
rm Remove files
rmdir Remove folder(s)
rsync Remote file copy (Synchronize file trees)

screen Terminal window manager
scp Secure copy (remote file copy)
sdiff  Merge two files interactively
sed Stream Editor
select Accept keyboard input
seq Print numeric sequences
set Manipulate shell variables and functions
sftp  Secure File Transfer Program
shift  Shift positional parameters
shopt  Shell Options
shutdown  Shutdown or restart linux
sleep Delay for a specified time
sort  Sort text files
source Run commands from a file `.'
split Split a file into fixed-size pieces
ssh Secure Shell client (remote login program)
strace Trace system calls and signals
su Substitute user identity
sum Print a checksum for a file
symlink  Make a new name for a file
sync  Synchronize data on disk with memory

tail  Output the last part of files
tar Tape ARchiver
tee Redirect output to multiple files
test Evaluate a conditional expression
time Measure Program running time
times User and system times
touch Change file timestamps
top List processes running on the system
traceroute  Trace Route to Host
trap  Run a command when a signal is set(bourne)
tr Translate, squeeze, and/or delete characters
true  Do nothing, successfully
tsort  Topological sort
tty Print filename of terminal on stdin
type  Describe a command

ulimit Limit user resources
umask  Users file creation mask
umount Unmount a device
unalias  Remove an alias
uname  Print system information
unexpand  Convert spaces to tabs
uniq  Uniquify files
units  Convert units from one scale to another
unset  Remove variable or function names
unshar Unpack shell archive scripts
until  Execute commands (until error)
useradd  Create new user account
usermod  Modify user account
users  List users currently logged in
uuencode  Encode a binary file
uudecode  Decode a file created by uuencode

v Verbosely list directory contents (`ls -l -b')
vdir  Verbosely list directory contents (`ls -l -b')
vi  Text Editor

watch  Execute/display a program periodically
wc  Print byte, word, and line counts
whereis Report all known instances of a command 
which  Locate a program file in the user's path.
while  Execute commands
who Print all usernames currently logged in
whoami Print the current user id and name (`id -un')
Wget  Retrieve web pages or files via HTTP, HTTPS or FTP

xargs  Execute utility, passing constructed argument list(s)
yes  Print a string until interrupted

.period Run commands from a file
###  Comment / Remark