Одавно је прошло време када се за сваку озбиљнију интервенцију на систему у Linux-у морало ићи у терминал, данас постоји брдо графичких програма помоћу којих једним кликом можете завршити посао за који Вам је раније требало

Представљам Вам преглед најкориснијих операција. Примери означени са • могу се без измене ископирати и ижвршити у терминалу. Све команде су тестиране под Fedora и Ubuntu Linux-ом.

Command		Description
•	apropos whatis	Show commands pertinent to string. See also threadsafe
•	man -t man	ps2pdf – > man.pdf	make a pdf of a manual page
	which command	Show full path name of command
	time command	See how long a command takes
•	time cat	Start stopwatch. Ctrl-d to stop. See also sw
•	nice info	Run a low priority command (The „info“ reader in this case)
•	renice 19 -p $$	Make shell (script) low priority. Use for non interactive tasks
dir navigation
•	cd –	Go to previous directory
•	cd	Go to $HOME directory
	(cd dir && command)	Go to dir, execute command and return to current dir
•	pushd .	Put current dir on stack so you can popd back to it
file searching
•	alias l=‚ls -l –color=auto‘	quick dir listing
•	ls -lrt	List files by date. See also newest and find_mm_yyyy
•	ls /usr/bin	pr -T9 -W$COLUMNS	Print in 9 columns to width of terminal
	find -name ‚*.[ch]‘	xargs grep -E ‚expr‘	Search ‚expr‘ in this dir and below. See also findrepo
	find -type f -print0	xargs -r0 grep -F ‚example‘	Search all regular files for ‚example‘ in this dir and below
	find -maxdepth 1 -type f	xargs grep -F ‚example‘	Search all regular files for ‚example‘ in this dir
	find -maxdepth 1 -type d	while read dir; do echo $dir; echo cmd2; done	Process each item with multiple commands (in while loop)
•	find -type f ! -perm –444	Find files not readable by all (useful for web site)
•	find -type d ! -perm –111	Find dirs not accessible by all (useful for web site)
•	locate -r ‚file[^/]*\.txt‘	Search cached index for names. This re is like glob file.txt
•	look reference	Quickly search (sorted) dictionary for prefix
•	grep –color reference /usr/share/dic­t/words	Highlight occurances of regular expression in dictionary
archives and compression
	gpg -c file	Encrypt file
	gpg file.gpg	Decrypt file
	tar -c dir/	bzip2 > dir.tar.bz2	Make compressed archive of dir/
	bzip2 -dc dir.tar.bz2	tar -x	Extract archive (use gzip instead of bzip2 for tar.gz files)
	tar -c dir/	gzip	gpg -c	ssh user@remote ‚dd of=dir.tar.gz.gpg‘	Make encrypted archive of dir/ on remote machine
	find dir/ -name ‚*.txt‘	tar -c –files-from=-	bzip2 > dir_txt.tar.bz2	Make archive of subset of dir/ and below
	find dir/ -name ‚*.txt‘	xargs cp -a –target-directory=dir_txt/ –parents	Make copy of subset of dir/ and below
	( tar -c /dir/to/copy )	( cd /where/to/ && tar -x -p )	Copy (with permissions) copy/ dir to /where/to/ dir
	( cd /dir/to/copy && tar -c . )	( cd /where/to/ && tar -x -p )	Copy (with permissions) contents of copy/ dir to /where/to/
	( tar -c /dir/to/copy )	ssh -C user@remote ‚cd /where/to/ && tar -x -p‘	Copy (with permissions) copy/ dir to remote:/where/to/ dir
	dd bs=1M if=/dev/sda	gzip	ssh user@remote ‚dd of=sda.gz‘	Backup harddisk to remote machine
rsync (Network efficient file copier: Use the –dry-run option for testing)
	rsync -P rsync://rsync­.server.com/pat­h/to/file file	Only get diffs. Do multiple times for troublesome downloads
	rsync –bwlimit=1000 fromfile tofile	Locally copy with rate limit. It's like nice for I/O
	rsync -az -e ssh –delete ~/public_html/ remote.com:‚~/pu­blic_html‘	Mirror web site (using compression and encryption)
	rsync -auz -e ssh remote:/dir/ . && rsync -auz -e ssh . remote:/dir/	Synchronize current directory with remote one
ssh (Secure SHell)
	ssh $USER@$HOST command	Run command on $HOST as $USER (default command=shell)
•	ssh -f -Y $USER@$HOSTNAME xeyes	Run GUI command on $HOSTNAME as $USER
	scp -p -r $USER@$HOST: file dir/	Copy with permissions to $USER's home directory on $HOST
	ssh -g -L 8080:localhost:80 root@$HOST	Forward connections to $HOSTNAME:8080 out to $HOST:80
	ssh -R 1434:imap:143 root@$HOST	Forward connections from $HOST:1434 in to imap:143
wget (multi purpose download tool)
•	(cd cli && wget -nd -pHEKk http://www.pixelbeat.org/cmdline.html)	Store local browsable version of a page to the current dir
	wget -c http://www.example.com/large.file	Continue downloading a partially downloaded file
	wget -r -nd -np -l1 -A ‚*.jpg‘ http://www.example.com/dir/	Download a set of files to the current directory
	wget ftp://remote/file[1–9].iso/	FTP supports globbing directly
•	wget -q -O- http://www.pixelbeat.org/timeline.html	grep ‚a href‘	head	Process output directly
	echo ‚wget url‘	at 01:00	Download url at 1AM to current dir
	wget –limit-rate=20k url	Do a low priority download (limit to 20KB/s in this case)
	wget -nv –spider –force-html -i bookmarks.html	Check links in a file
	wget –mirror http://www.example.com/	Efficiently update a local copy of a site (handy from cron)
networking (Note ifconfig, route, mii-tool, nslookup commands are obsolete)
	ethtool . eth0	Show status of ethernet interface eth0
	ethtool –change eth0 autoneg off speed 100 duplex full	Manually set ethernet interface speed
	iwconfig . eth1	Show status of wireless interface eth1
	iwconfig eth1 rate 1Mb/s fixed	Manually set wireless interface speed
•	iwlist . scan	List wireless networks in range
•	ip . link show	List network interfaces
	ip link set dev eth0 name wan	Rename interface eth0 to wan
	ip link set dev eth0 up	Bring interface eth0 up (or down)
•	ip addr show	List addresses for interfaces
	ip addr add 1.2.3.4/24 brd + dev eth0	Add (or del) ip and mask (255.255.255.0)
•	ip route show	List routing table
	ip route add default via 1.2.3.254	Set default gateway to 1.2.3.254
•	tc . qdisc add dev lo root handle 1:0 netem delay 20msec	Add 20ms latency to loopback device (for testing)
•	tc qdisc del dev lo root	Remove latency added above
•	host pixelbeat.org	Lookup DNS ip address for name or vice versa
•	hostname -i	Lookup local ip address (equivalent to host hostname)
•	whois pixelbeat.org	Lookup whois info for hostname or ip address
•	netstat -tupl	List internet services on a system
•	netstat -tup	List active connections to/from system
windows networking (Note samba is the package that provides all this windows specific networking support)
•	smbtree	Find windows machines. See also findsmb
	nmblookup -A 1.2.3.4	Find the windows (netbios) name associated with ip address
	smbclient -L windows_box	List shares on windows machine or samba server
	mount -t smbfs -o fmask=666,guest //windows_box/share /mnt/share	Mount a windows share
	echo ‚message‘	smbclient -M windows_box	Send popup to windows machine (off by default in XP sp2)
text manipulation (Note sed uses stdin and stdout. Newer versions support inplace editing with the -i option)
	sed ‚s/string1/strin­g2/g‘	Replace string1 with string2
	sed ‚s/\(.*)1/\12/g‘	Modify anystring1 to anystring2
	sed ‚/ *#/d; /^ *$/d‘	Remove comments and blank lines
	sed ‚:a; /\\$/N; s/\\\n//; ta‘	Concatenate lines with trailing \
	sed ‚s/[ \t]*$//‘	Remove trailing spaces from lines
	sed ‚s/\([\\`\\"$­\\\\])/\\\1/g‘	Escape shell metacharacters active within double quotes
•	seq 10	sed „s/^/      /; s/ *\(.\{7,\})/\1/“	Right align numbers
	sed -n ‚1000p;1000q .‘	Print 1000th line
	sed -n ‚10,20p;20q .‘	Print lines 10 to 20
	sed -n 's/.
	sed -i 42d ~/.ssh/known_hosts	Delete a particular line
	sort -t. -k1,1n -k2,2n -k3,3n -k4,4n	Sort IPV4 ip addresses
•	echo ‚Test‘	tr ‚[:lower:]‘ ‚[:upper:]‘	Case conversion
•	tr -dc ‚[:print:]‘ < /dev/urandom	Filter non printable characters
•	history	wc -l	Count lines
set operations (Note you can export LANG=C for speed. Also these assume no duplicate lines within a file)
	sort file1 file2	uniq	Union . of unsorted files
	sort file1 file2	uniq -d	Intersection . of unsorted files
	sort file1 file1 file2	uniq -u	Difference . of unsorted files
	sort file1 file2	uniq -u	Symmetric Difference . of unsorted files
	join -a1 -a2 file1 file2	Union of sorted files
	join file1 file2	Intersection of sorted files
	join -v2 file1 file2	Difference of sorted files
	join -v1 -v2 file1 file2	Symmetric Difference of sorted files
math
•	echo ‚(1 + sqrt(5))/2‘	bc -l	Quick math (Calculate φ). See also bc
•	echo ‚pad=20; min=64; (100106)/((pa­d+min)‘	bc	More complex (int) e.g. This shows max FastE packet rate
•	echo ‚pad=20; min=64; print (100E6)/((pad­+min)*8)‘	python	Python handles scientific notation
•	echo ‚pad=20; plot [64:1518] (10010**6)/((­pad+x)‘	gnuplot -persist	Plot FastE packet rate vs packet size
•	echo ‚obase=16; ibase=10; 64206‘	bc	Base conversion (decimal to hexadecimal)
•	echo $((0×2dec))	Base conversion (hex to dec) ((shell arithmetic expansion))
•	units -t ‚100m/9.69s‘ ‚miles/hour‘	Unit conversion (metric to imperial)
•	units -t ‚500GB‘ ‚GiB‘	Unit conversion (SI . to IEC . prefixes)
•	units -t ‚1 googol‘	Definition lookup
•	seq 100	(tr ‚\n‘ +; echo 0)	bc	Add a column of numbers. See also add and funcpy
calendar
•	cal –3	Display a calendar
•	cal 9 1752	Display a calendar for a particular month year
•	date -d fri	What date is it this friday. See also day
•	[ $(date -d „tomorrow“ +%d) = „01“ ]		exit	exit a script unless it's the last day of the month
•	date –date=‚25 Dec‘ +%A	What day does xmas fall on, this year
•	date –date=‚@2147483647‘	Convert seconds since the epoch (1970–01–01 UTC) to date
•	TZ=‚:America/Los_An­geles‘ date	What time is it on West coast of US (use tzselect to find TZ)
	echo „mail -s ‚get the train‘ P@draigBrady.com < /dev/null“	at 17:45	Email reminder
•	echo „DISPLAY=$DISPLAY xmessage cooker“	at „NOW + 30 minutes“	Popup reminder
locales
•	printf „%'d\n“ 1234	Print number with thousands grouping appropriate to locale
•	BLOCK_SIZE=\'1 ls -l	get ls to do thousands grouping appropriate to locale
•	echo „I live in locale territory“	Extract info from locale database
•	LANG=en_IE.utf8 locale int_prefix	Lookup locale info for specific country. See also ccodes
•	locale	cut -d= -f1	xargs locale -kc	less	List fields available in locale database
recode (Obsoletes iconv, dos2unix, unix2dos)
•	recode -l	less	Show available conversions (aliases on each line)
	recode windows-1252.. file_to_change.txt	Windows „ansi“ to local charset (auto does CRLF conversion)
	recode utf-8/CRLF.. file_to_change.txt	Windows utf8 to local charset
	recode iso-8859–15..utf8 file_to_change.txt	Latin9 (western europe) to utf8
	recode ../b64 < file.txt > file.b64	Base64 encode
	recode /qp.. < file.txt > file.qp	Quoted printable decode
	recode ..HTML < file.txt > file.html	Text to HTML
•	recode -lf windows-1252	grep euro	Lookup table of characters
•	echo -n 0×80	recode latin-9/x1..dump	Show what a code represents in latin-9 charmap
•	echo -n 0×20AC	recode ucs-2/x2..latin-9/x	Show latin-9 encoding
•	echo -n 0×20AC	recode ucs-2/x2..utf-8/x	Show utf-8 encoding
CDs .
	gzip < /dev/cdrom > cdrom.iso.gz	Save copy of data cdrom
	mkisofs -V LABEL -r dir	gzip > cdrom.iso.gz	Create cdrom image from contents of dir
	mount -o loop cdrom.iso /mnt/dir	Mount the cdrom image at /mnt/dir (read only)
	cdrecord -v dev=/dev/cdrom blank=fast	Clear a CDRW
	gzip -dc cdrom.iso.gz	cdrecord -v dev=/dev/cdrom –	Burn cdrom image (use dev=ATAPI -scanbus to confirm dev)
	cdparanoia -B	Rip audio tracks from CD to wav files in current dir
	cdrecord -v dev=/dev/cdrom -audio *.wav	Make audio CD from all wavs in current dir (see also cdrdao)
	oggenc –tracknum=‚track‘ track.cdda.wav -o ‚track.ogg‘	Make ogg file from wav file
disk space (See also FSlint)
•	ls -lSr	Show files by size, biggest last
•	du -s *	sort -k1,1rn	head	Show top disk users in current dir. See also dutop
•	df -h	Show free space on mounted filesystems
•	df -i	Show free inodes on mounted filesystems
•	fdisk . -l	Show disks partitions sizes and types (run as root)
•	rpm -q -a –qf ‚%10{SIZE}\t%{NA­ME}\n‘	sort -k1,1n	List all packages by installed size (Bytes) on rpm distros
•	dpkg-query -W -f=‚${Installed-Size;10}\t${Pac­kage}\n‘	sort -k1,1n	List all packages by installed size (KBytes) on deb distros
•	dd bs=1 seek=2TB if=/dev/null of=ext3.test	Create a large test file (taking no space). See also truncate
monitoring/de­bugging
•	tail -f /var/log/messages	Monitor messages in a log file
•	strace -c ls >/dev/null	Summarise/profile system calls made by command
•	strace -f -e open ls >/dev/null	List system calls made by command
•	ltrace -f -e getenv ls >/dev/null	List library calls made by command
•	lsof . -p $$ .	List paths that process id has open
•	lsof ~	List processes that have specified path open
•	tcpdump not port 22	Show network traffic except ssh. See also tcpdump_not_me
•	ps -e -o pid,args –forest	List processes in a hierarchy
•	ps -e -o pcpu,cpu,ni­ce,state,cputi­me,args –sort pcpu	sed ‚/^ 0.0 /d‘	List processes by % cpu usage
•	ps -e -orss=,args=	sort -b -k1,1n	pr -TW$COLUMNS	List processes by mem usage. See also ps_mem.py
•	ps -C firefox-bin -L -o pid,tid,pcp­u,state	List all threads for a particular process
•	ps -p 1,2	List info for particular process IDs
•	last reboot	Show system reboot history
•	free -m	Show amount of (remaining) RAM (-m displays in MB)
•	watch -n.1 ‚cat /proc/interrupts‘	Watch changeable data continuously
system information (see also sysinfo) (‚#‘ means root access is required)
•	uname -a	Show kernel version and system architecture
•	head -n1 /etc/issue	Show name and version of distribution
•	cat /proc/partitions	Show all partitions registered on the system
•	grep MemTotal /proc/meminfo	Show RAM total seen by the system
•	grep „model name“ /proc/cpuinfo	Show CPU(s) info
•	lspci . -tv	Show PCI info
•	lsusb . -tv	Show USB info
•	mount	column -t	List mounted filesystems on the system (and align output)
#	dmidecode -q	less	Display SMBIOS/DMI information
#	smartctl -A /dev/sda	grep Power_On_Hours	How long has this disk (system) been powered on in total
#	hdparm -i /dev/sda	Show info about disk sda
#	hdparm -tT /dev/sda	Do a read speed test on disk sda
#	badblocks -s /dev/sda	Test for unreadable blocks on disk sda
interactive (see also linux keyboard shortcuts)
•	readline	Line editor used by bash, python, bc, gnuplot, …
•	screen	Virtual terminals with detach capability, …
•	mc	Powerful file manager that can browse rpm, tar, ftp, ssh, …
•	gnuplot	Interactive/scrip­table graphing
•	links	Web browser
•	xdg-open http://www.pixelbeat.org/	open a file or url with the registered desktop application
miscellaneous
•	alias hd=‚od -Ax -tx1z -v‘	Handy hexdump. (usage e.g.: • hd /proc/self/cmdline	less)
•	alias realpath=‚readlink -f‘	Canonicalize path. (usage e.g.: • realpath ~/../$USER)
•	set	grep $USER	Search current environment
	touch -c -t 0304050607 file	Set file timestamp (YYMMDDhhmm)
•	python -c „import SimpleHTTPServer as ws; ws.test()“	Serve current directory tree at http://$HOSTNA­ME:8000/