07-03 Linux Commands

8/2/2019 07-03 Linux Commands

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Command Description

apropos whatisShow commandspertinent to string. Seealsothreadsafe

man-t ascii | ps2pdf - > ascii.pdfmake a pdf of a manual

page

which commandShow full path name ofcommand

time commandSee how long a commandtakes

time catStart stopwatch. Ctrl-d tostop. See alsosw

dir navigation

cd - Go to previous directory cd Go to $HOME directory

(cd dir && command) Go to dir, executecommand and return tocurrent dir

pushd .Put current dir on stack soyou can popd back to it

file searching

aliasl='ls -l --color=auto' quick dir listing

ls -lrtList files by date. Seealsonewestandfind_mm_yyyy

ls /usr/bin | pr -T9 -W$COLUMNSPrint in 9 columns to

width of terminal

find -name '*.[ch]' | xargs grep -E 'expr'Search 'expr' in this dirand below. See alsofindrepo

find -type f -print0 | xargs -r0 grep -F 'example'Search all regular files for'example' in this dir andbelow

find -maxdepth 1 -type f | xargs grep -F 'example'Search all regular files for'example' in this dir

find -maxdepth 1 -type d | whilereaddir; do echo $dir; echo cmd2;

done

Process each item withmultiple commands (inwhile loop)

find -type f ! -perm -444Find files not readable byall (useful for web site)

find -type d ! -perm -111Find dirs not accessibleby all (useful for website)

locate -r 'file[^/]*\.txt' Search cached index for
http://www.pixelbeat.org/scripts/threadsafehttp://www.pixelbeat.org/scripts/threadsafehttp://www.pixelbeat.org/scripts/threadsafehttp://www.pixelbeat.org/lkdb/less.htmlhttp://www.pixelbeat.org/lkdb/less.htmlhttp://www.pixelbeat.org/lkdb/less.htmlhttp://www.pixelbeat.org/scripts/stopwatch/http://www.pixelbeat.org/scripts/stopwatch/http://www.pixelbeat.org/scripts/stopwatch/http://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/scripts/newesthttp://www.pixelbeat.org/scripts/newesthttp://www.pixelbeat.org/scripts/newesthttp://www.pixelbeat.org/scripts/find_mm_yyyyhttp://www.pixelbeat.org/scripts/find_mm_yyyyhttp://www.pixelbeat.org/scripts/findrepohttp://www.pixelbeat.org/scripts/findrepohttp://www.pixelbeat.org/programming/readline/http://www.pixelbeat.org/programming/readline/http://www.pixelbeat.org/programming/readline/http://www.pixelbeat.org/programming/readline/http://www.pixelbeat.org/scripts/findrepohttp://www.pixelbeat.org/scripts/find_mm_yyyyhttp://www.pixelbeat.org/scripts/newesthttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/scripts/stopwatch/http://www.pixelbeat.org/lkdb/less.htmlhttp://www.pixelbeat.org/scripts/threadsafe


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names. This re is likeglob *file*.txt

look referenceQuickly search (sorted)dictionary for prefix

grep--colorreference /usr/share/dict/words

Highlight occurances of

regular expression indictionary

archives and compression

gpg -c file Encrypt file

gpg file.gpg Decrypt file

tar -c dir/ | bzip2 > dir.tar.bz2Make compressed archiveof dir/

bzip2 -dc dir.tar.bz2 | tar -xExtract archive (use gzipinstead of bzip2 for tar.gzfiles)

tar -c dir/ | gzip | gpg -c | ssh user@remote 'dd of=dir.tar.gz.gpg'Make encrypted archiveof dir/ on remote machine

find dir/ -name '*.txt' | tar -c --files-from=- | bzip2 > dir_txt.tar.bz2Make archive of subset ofdir/ and below

find dir/ -name '*.txt' | xargs cp -a --target-directory=dir_txt/ --parents

Make copy of subset ofdir/ 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 toremote:/where/to/ dir

dd bs=1M if=/dev/sda | gzip | ssh user@remote 'dd of=sda.gz'Backup harddisk toremote machine

rsync (Network efficient file copier: Use the --dry-run option for testing)

rsync -P rsync://rsync.server.com/path/to/file fileOnly get diffs. Domultiple times fortroublesome downloads

rsync --bwlimit=1000 fromfile tofileLocally copy with ratelimit. It's like nice for I/O

rsync -az -e ssh --delete ~/public_html/ remote.com:'~/public_html'Mirror web site (usingcompression andencryption)

rsync -auz -e ssh remote:/dir/. && rsync -auz -e ssh . remote:/dir/Synchronize currentdirectory with remote one

ssh (Secure SHell)

ssh $USER@$HOST command Run command on $HOST
http://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrc


3/14

as $USER (defaultcommand=shell)

ssh -f -Y $USER@$HOSTNAME xeyesRun GUI command on$HOSTNAME as $USER

scp -p -r $USER@$HOST: file dir/

Copy with permissions to

$USER's home directoryon $HOST

scp -c arcfour $USER@$LANHOST: bigfileUse faster crypto for localLAN. This might saturateGigE

ssh -g -L 8080:localhost:80 root@$HOSTForward connections to$HOSTNAME:8080 outto $HOST:80

ssh -R 1434:imap:143 root@$HOSTForward connectionsfrom $HOST:1434 in toimap:143

ssh-copy-id $USER@$HOSTInstall $USER's publickey on $HOST forpassword-less log in

wget (multi purpose download tool)

(cd dir/ && wget -nd -pHEKkhttp://www.pixelbeat.org/cmdline.html)

Store local browsableversion of a page to thecurrent dir

wget -c http://www.example.com/large.fileContinue downloading apartially downloaded file

wget -r -nd -np -l1 -A '*.jpg' http://www.example.com/dir/Download a set of files to

the current directorywget ftp://remote/file[1-9].iso/

FTP supports globbingdirectly

wget -q -O- http://www.pixelbeat.org/timeline.html | grep 'a href' |head

Process output directly

echo 'wget url' | at 01:00Download url at 1AM tocurrent dir

wget --limit-rate=20k urlDo a low prioritydownload (limit to20KB/sin this case)

wget -nv --spider --force-html -i bookmarks.html Check links in a file

wget --mirror http://www.example.com/Efficiently update a localcopy of a site (handyfrom cron)

networking (Note ifconfig, route, mii-tool, nslookup commands are obsolete)

ethtool eth0Show status of ethernetinterface eth0

ethtool --change eth0 autoneg off speed 100 duplex full Manually set ethernet
http://www.pixelbeat.org/speeds.htmlhttp://www.pixelbeat.org/speeds.htmlhttp://www.pixelbeat.org/speeds.html


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interface speed

iwconfig eth1Show status of wirelessinterface eth1

iwconfig eth1 rate 1Mb/s fixedManually set wirelessinterface speed

iwlist scan List wireless networks inrange

ip link show List network interfaces

ip link set dev eth0 name wanRename interface eth0 towan

ip link set dev eth0 upBring interface eth0 up(or down)

ip addr showList addresses forinterfaces

ip addr add 1.2.3.4/24 brd + dev eth0Add (or del) ip and mask(255.255.255.0)

ip route show List routing table

ip route add default via 1.2.3.254Set default gateway to1.2.3.254

host pixelbeat.orgLookup DNS ip addressfor name or vice versa

hostname -iLookup local ip address(equivalent to host`hostname`)

whois pixelbeat.orgLookup whois info forhostname or ip address

netstat -tupl List internet services on asystem

netstat -tupList active connectionsto/from system

windows networking (Note samba is the package that provides all this windows specificnetworking support)

smbtreeFind windows machines.See also findsmb

nmblookup -A 1.2.3.4Find the windows(netbios) name associatedwith ip address

smbclient -L windows_boxList shares on windowsmachine or samba server

mount -t smbfs -o fmask=666,guest //windows_box/share /mnt/share Mount a windows share

echo 'message' | smbclient -M windows_boxSend popup to windowsmachine (off by default inXP sp2)

text manipulation (Note sed uses stdin and stdout. Newer versions support inplace editing with


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the -i option)

sed 's/string1/string2/g'Replace string1 withstring2

sed 's/$.*$1/\12/g'Modify anystring1 toanystring2

sed '/ *#/d; /^ *$/d' Remove comments andblank lines

sed ':a; /\\$/N; s/\\\n//; ta'Concatenate lines withtrailing \

sed 's/[ \t]*$//'Remove trailing spacesfrom lines

sed 's/$[`"$\]$/\\\1/g'Escape shellmetacharacters activewithin double quotes

seq 10 | sed "s/^/ /; s/ *$.\{7,\}$/\1/" Right align numberssed -n '1000{p;q}' Print 1000th line

sed -n '10,20p;20q' Print lines 10 to 20

sed -n 's/.*$.*$.*/\1/ip;T;q'Extract title from HTMLweb page

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/urandomFilter non printablecharacters

tr -s '[:blank:]' '\t'


6/14

echo 'pad=20; min=64; (100*10^6)/((pad+min)*8)' | bcMore complex (int) e.g.This shows max FastEpacket rate

echo 'pad=20; min=64; print (100E6)/((pad+min)*8)' | pythonPython handles scientificnotation

echo 'pad=20; plot [64:1518] (100*10**6)/((pad+x)*8)' | gnuplot -persist

Plot FastE packet rate vspacket size

echo 'obase=16; ibase=10; 64206' | bcBase conversion (decimalto hexadecimal)

echo $((0x2dec))Base conversion (hex todec) ((shell arithmeticexpansion))

units -t '100m/9.58s' 'miles/hour'Unit conversion (metricto imperial)

units -t '500GB' 'GiB'Unit conversion (SI toIEC prefixes)

units -t '1 googol' Definition lookup

seq 100 | (tr '\n' +; echo 0) | bcAdd a column ofnumbers. See alsoaddandfuncpy

calendar

cal -3 Display a calendar

cal 9 1752Display a calendar for aparticular month year

date -d friWhat date is it this friday.See alsoday

[ $(date -d "tomorrow" +%d) = "01" ] || exit exit a script unless it's thelast day of the month

date --date='25 Dec' +%AWhat day does xmas fallon, this year

date --date='@2147483647'Convert seconds since theepoch (1970-01-01 UTC)to date

TZ='America/Los_Angeles' dateWhat time is it on westcoast of US (use tzselectto find TZ)

date --date='TZ="America/Los_Angeles" 09:00 next Fri'What's the local time for

9AM next Friday on westcoast US

locales

printf "%'d\n" 1234Print number withthousands groupingappropriate to locale

BLOCK_SIZE=\'1 ls -l Use locale thousands
http://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/scripts/bchttp://www.pixelbeat.org/misc/usain_bolt/http://www.pixelbeat.org/misc/usain_bolt/http://www.pixelbeat.org/misc/usain_bolt/http://www.pixelbeat.org/scripts/addhttp://www.pixelbeat.org/scripts/addhttp://www.pixelbeat.org/scripts/addhttp://www.pixelbeat.org/scripts/funcpyhttp://www.pixelbeat.org/scripts/funcpyhttp://www.pixelbeat.org/scripts/funcpyhttp://www.pixelbeat.org/scripts/dayhttp://www.pixelbeat.org/scripts/dayhttp://www.pixelbeat.org/scripts/dayhttp://www.pixelbeat.org/scripts/dayhttp://www.pixelbeat.org/scripts/funcpyhttp://www.pixelbeat.org/scripts/addhttp://www.pixelbeat.org/misc/usain_bolt/


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grouping in ls. See alsol

echo "I live in `locale territory`"Extract info from localedatabase

LANG=en_IE.utf8 locale int_prefixLookup locale info forspecific country. See also

ccodes

locale | cut -d= -f1 | xargs locale -kc | lessList fields available inlocale database

recode (Obsoletes iconv, dos2unix, unix2dos)

recode -l | lessShow availableconversions (aliases oneach line)

recode windows-1252.. file_to_change.txtWindows "ansi" to localcharset (auto does CRLFconversion)

recode utf-8/CRLF.. file_to_change.txt

Windows utf8 to local

charset

recode iso-8859-15..utf8 file_to_change.txtLatin9 (western europe)to utf8

recode ../b64 < file.txt > file.b64 Base64 encode

recode /qp.. < file.qp > file.txt Quoted printable decode

recode ..HTML < file.txt > file.html Text to HTML

recode -lf windows-1252 | grep euroLookuptable ofcharacters

echo -n 0x80 | recode latin-9/x1..dumpShow what a coderepresents in latin-9

charmap echo -n 0x20AC | recode ucs-2/x2..latin-9/x Show latin-9 encoding echo -n 0x20AC | recode ucs-2/x2..utf-8/x Show utf-8 encodingCDs

gzip < /dev/cdrom > cdrom.iso.gz Save copy of data cdrom

mkisofs -V LABEL -r dir | gzip > cdrom.iso.gzCreate cdrom image fromcontents of dir

mount -o loop cdrom.iso /mnt/dirMount the cdrom imageat /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 (usedev=ATAPI -scanbus toconfirm dev)

cdparanoia -BRip audio tracks from CDto wav files in current dir

cdrecord -v dev=/dev/cdrom -audio -pad *.wavMake audio CD from allwavs in current dir (seealso cdrdao)
http://www.pixelbeat.org/scripts/lhttp://www.pixelbeat.org/scripts/lhttp://www.pixelbeat.org/scripts/lhttp://www.pixelbeat.org/scripts/ccodeshttp://www.pixelbeat.org/scripts/ccodeshttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/docs/utf8.htmlhttp://www.pixelbeat.org/scripts/ccodeshttp://www.pixelbeat.org/scripts/l


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oggenc --tracknum='track' track.cdda.wav -o 'track.ogg'Make ogg file from wavfile

disk space (See alsoFSlint)

ls -lSrShow files by size,biggest last

du -s * | sort -k1,1rn | headShow top disk users incurrent dir. See alsodutop

du -hs /home/* | sort -k1,1hSort paths by easy tointerpret disk usage

df -hShow free space onmounted filesystems

df -iShow free inodes onmounted filesystems

fdisk -lShow disks partitionssizes and types (run asroot)

rpm-q -a --qf '%10{SIZE}\t%{NAME}\n' | sort -k1,1nList allpackagesbyinstalled size (Bytes) onrpm distros

dpkg-query -W -f='${Installed-Size;10}\t${Package}\n' | sort -k1,1nList allpackagesbyinstalled size (KBytes) ondeb distros

dd bs=1 seek=2TB if=/dev/null of=ext3.testCreate a large test file(taking no space). Seealsotruncate

> file truncate data of file orcreate an empty filemonitoring/debugging

tail -f /var/log/messagesMonitor messagesin alog file

strace -c ls >/dev/nullSummarise/profile systemcalls made by command

strace -f -e open ls >/dev/nullList system calls made bycommand

strace -f -e trace=write -e write=1,2 ls >/dev/nullMonitor what's written tostdout and stderr

ltrace -f -e getenv ls >/dev/null List library calls made bycommand

lsof -p $$List paths that process idhas open

lsof ~List processes that havespecified path open

tcpdump not port 22 Show network traffic
http://www.pixelbeat.org/fslint/http://www.pixelbeat.org/fslint/http://www.pixelbeat.org/fslint/http://www.pixelbeat.org/scripts/dutophttp://www.pixelbeat.org/scripts/dutophttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/scripts/truncatehttp://www.pixelbeat.org/scripts/truncatehttp://www.pixelbeat.org/scripts/truncatehttp://www.pixelbeat.org/docs/web/access_log/monitoring.htmlhttp://www.pixelbeat.org/docs/web/access_log/monitoring.htmlhttp://www.pixelbeat.org/docs/web/access_log/monitoring.htmlhttp://www.pixelbeat.org/scripts/truncatehttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/docs/packaging.htmlhttp://www.pixelbeat.org/scripts/dutophttp://www.pixelbeat.org/fslint/


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except ssh. See alsotcpdump_not_me

ps -e -o pid,args --forestList processes in ahierarchy

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$COLUMNSList processes by mem(KB) usage. See alsops_mem.py

ps -C firefox-bin -L -o pid,tid,pcpu,stateList all threads for aparticular process

ps -p 1,$$ -o etime=List elapsed wall time forparticular process IDs

last rebootShow system reboothistory

free -mShow amount of

(remaining) RAM (-mdisplays in MB)

watch -n.1 'cat /proc/interrupts'Watch changeable datacontinuously

udevadm monitorMonitor udev events tohelp configure rules

system information (see alsosysinfo) ('#' means root access is required)

uname -aShow kernel version andsystem architecture

head -n1 /etc/issueShow name and version

of distribution cat /proc/partitions

Show all partitionsregistered on the system

grep MemTotal /proc/meminfoShow RAM total seen bythe system

grep "model name" /proc/cpuinfo Show CPU(s) info lspci -tv Show PCI info lsusb -tv Show USB info

mount | column -tList mounted filesystemson the system (and alignoutput)

grep -F capacity: /proc/acpi/battery/BAT0/infoShow state of cells inlaptop battery

# dmidecode -q | lessDisplay SMBIOS/DMIinformation

# smartctl -A /dev/sda | grep Power_On_HoursHow long has this disk(system) been poweredon in total
http://www.pixelbeat.org/scripts/tcpdump_not_mehttp://www.pixelbeat.org/scripts/tcpdump_not_mehttp://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.pixelbeat.org/scripts/sysinfohttp://www.pixelbeat.org/scripts/sysinfohttp://www.pixelbeat.org/scripts/sysinfohttp://www.pixelbeat.org/scripts/sysinfohttp://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.pixelbeat.org/scripts/tcpdump_not_me


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# hdparm -i /dev/sda Show info about disk sda

# hdparm -tT /dev/sdaDo a read speed test ondisk sda

# badblocks -s /dev/sdaTest for unreadableblocks on disk sda

interactive (see alsolinux keyboard shortcuts)

readlineLine editor used by bash,python, bc, gnuplot, ...

screenVirtual terminals withdetach capability, ...

mcPowerful file managerthat can browse rpm, tar,ftp, ssh, ...

gnuplotInteractive/scriptablegraphing

links Web browser

xdg-open .open a file or url with theregistered desktopapplication

Command Description

grep . /proc/sys/net/ipv4/*List the contents of flagfiles

set | grep $USERSearch currentenvironment

tr '\0' '\n' < /proc/$$/environDisplay the startupenvironment for any

process

echo $PATH | tr : '\n'Display the $PATH oneper line

kill -0 $$ && echo process exists and can accept signalsCheck for the existenceof a process (pid)

find /etc -readable | xargs less -K -p'*ntp' -j $((${LINES:-25}/2))Search paths and datawith full context. Use nto iterate

Low impact admin

#apt-get install "package" -o Acquire::http::Dl-Limit=42 \-o Acquire::Queue-mode=access

Rate limit apt-get to42KB/s

echo 'wget url' | at 01:00Download url at 1AM tocurrent dir

# apache2ctl configtest && apache2ctl gracefulRestart apache if config isOK

nice openssl speed sha1Run a low prioritycommand (opensslbenchmark)
http://www.pixelbeat.org/lkdb/http://www.pixelbeat.org/lkdb/http://www.pixelbeat.org/lkdb/http://www.pixelbeat.org/lkdb/readline.htmlhttp://www.pixelbeat.org/lkdb/readline.htmlhttp://www.pixelbeat.org/lkdb/readline.htmlhttp://www.pixelbeat.org/lkdb/screen.htmlhttp://www.pixelbeat.org/lkdb/screen.htmlhttp://www.pixelbeat.org/lkdb/screen.htmlhttp://www.pixelbeat.org/lkdb/mc.htmlhttp://www.pixelbeat.org/lkdb/mc.htmlhttp://www.pixelbeat.org/docs/web/access_log/analyzing.htmlhttp://www.pixelbeat.org/docs/web/access_log/analyzing.htmlhttp://www.pixelbeat.org/docs/web/access_log/analyzing.htmlhttp://www.pixelbeat.org/docs/env.htmlhttp://www.pixelbeat.org/docs/env.htmlhttp://www.pixelbeat.org/speeds.htmlhttp://www.pixelbeat.org/speeds.htmlhttp://www.pixelbeat.org/speeds.htmlhttp://www.pixelbeat.org/docs/env.htmlhttp://www.pixelbeat.org/docs/web/access_log/analyzing.htmlhttp://www.pixelbeat.org/lkdb/mc.htmlhttp://www.pixelbeat.org/lkdb/screen.htmlhttp://www.pixelbeat.org/lkdb/readline.htmlhttp://www.pixelbeat.org/lkdb/


11/14

renice 19 -p $$; ionice -c3 -p $$Make shell (script) lowpriority. Use for noninteractive tasks

Interactive monitoring

htop -d 5

Better top (scrollable, tree

view, lsof/straceintegration, ...)

iotop What's doing I/O# watch -d -n30 "niceps_mem.py| tail -n $((${LINES:-12}-2))" What's using RAM

# iftopWhat's using the network.See also iptraf

# mtr www.pixelbeat.orgping and traceroutecombined

Useful utilities

pv< /dev/zero > /dev/nullProgress Viewer for datacopying from files andpipes

wkhtml2pdfhttp://.../linux_commands.htmllinux_commands.pdf Make a pdf of a web page

timeout1 sleep 3run a command withbounded time. See alsotimeout

Networking

python -m SimpleHTTPServer

Serve current directorytree athttp://$HOSTNAME:8000/

openssl s_client -connect www.google.com:443 &0 |openssl x509 -dates -noout

Display the date range fora site's certs

curl -I www.pixelbeat.orgDisplay the serverheaders for a web site

# lsof -i tcp:80 What's using port 80

# httpd -SDisplay a list of apachevirtual hosts

vim scp://user@remote//path/to/fileEdit a remote file directlyin vim

curl -s http://www.pixelbeat.org/pixelbeat.asc | gpg --importImport a gpg key fromthe web

tc qdisc add dev lo root handle 1:0 netem delay 20msecAdd 20ms latency toloopback device (fortesting)

tc qdisc del dev lo rootRemove latency addedabove

Notification

echo "DISPLAY=$DISPLAY xmessage cooker" | at "NOW +30min" Popup reminder
http://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.pixelbeat.org/scripts/ps_mem.pyhttp://www.ivarch.com/programs/pv.shtmlhttp://www.ivarch.com/programs/pv.shtmlhttp://www.ivarch.com/programs/pv.shtmlhttp://code.google.com/p/wkhtmltopdf/http://code.google.com/p/wkhtmltopdf/http://code.google.com/p/wkhtmltopdf/http://www.pixelbeat.org/docs/linux_commands.pdfhttp://www.pixelbeat.org/docs/linux_commands.pdfhttp://www.pixelbeat.org/docs/linux_commands.pdfhttp://www.gnu.org/software/coreutils/manual/coreutils.html#timeout-invocationhttp://www.gnu.org/software/coreutils/manual/coreutils.html#timeout-invocationhttp://www.gnu.org/software/coreutils/manual/coreutils.html#timeout-invocationhttp://www.pixelbeat.org/scripts/timeouthttp://www.pixelbeat.org/scripts/timeouthttp://localhost:8000/http://localhost:8000/http://localhost:8000/http://localhost:8000/http://localhost:8000/http://www.pixelbeat.org/scripts/timeouthttp://www.gnu.org/software/coreutils/manual/coreutils.html#timeout-invocationhttp://www.pixelbeat.org/docs/linux_commands.pdfhttp://code.google.com/p/wkhtmltopdf/http://www.ivarch.com/programs/pv.shtmlhttp://www.pixelbeat.org/scripts/ps_mem.py


12/14

notify-send "subject" "message"Display a gnome popupnotification

echo "mail -s 'go home' [email protected] < /dev/null" | at 17:30 Email reminder

uuencode file name | mail -s subject [email protected] Send a file via email

ansi2html.sh| mail -a "Content-Type: text/html" [email protected]/Generate HTML

emailBetterdefault settings(useful in your.bashrc)

# tail -s.1 -f /var/log/messagesDisplay file additionsmore responsively

seq 100 | tail -n $((${LINES:-12}-2))Display as many lines aspossible without scrolling

# tcpdump -s0Capture full networkpackets

Useful functions/aliases (useful in your.bashrc)

md () { mkdir -p "$1" && cd "$1"; }Change to a new

directory strerror() { python -c "import os; print os.strerror($1)"; }

Display the meaning ofanerrno

plot() { { echo 'plot "-"' "$@"; cat; } | gnuplot -persist; }Plot stdin. (e.g: seq1000 | sed 's/.*/s(&)/' | bc-l | plot)

alias hd='od -Ax -tx1z -v'Handy hexdump. (usagee.g.: hd/proc/self/cmdline | less)

alias realpath='readlink -f'Canonicalize path. (usagee.g.: realpath

~/../$USER)Multimedia

DISPLAY=:0.0 import -window root orig.pngTake a (remote)screenshot

convert -filter catrom -resize'600x>' orig.png 600px_wide.pngShrinkto width,computer generatedimages or screenshots

mplayer -ao pcm -vo null -vc dummy /tmp/Flash*Extract audio from flashvideo to audiodump.wav

ffmpeg -i filename.aviDisplay info aboutmultimedia file

ffmpeg -f x11grab -s xga -r 25 -i :0 -sameq demo.mpgCapture video of an Xdisplay

DVD

for i in $(seq 9); do ffmpeg -i $i.avi -target pal-dvd $i.mpg; doneConvert video to thecorrect encoding andaspect for DVD

dvdauthor -odvd -t -v "pal,4:3,720xfull" *.mpg;dvdauthor -odvd -T Build DVD file system.
http://www.pixelbeat.org/scripts/ansi2html.shhttp://www.pixelbeat.org/scripts/ansi2html.shhttp://www.pixelbeat.org/docs/power_of_the_default.htmlhttp://www.pixelbeat.org/docs/power_of_the_default.htmlhttp://www.pixelbeat.org/docs/power_of_the_default.htmlhttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/scripts/errnohttp://www.pixelbeat.org/scripts/errnohttp://www.pixelbeat.org/scripts/errnohttp://www.imagemagick.org/Usage/resize/http://www.imagemagick.org/Usage/resize/http://www.imagemagick.org/Usage/resize/http://www.pixelbeat.org/docs/image_manipulation/#resizehttp://www.pixelbeat.org/docs/image_manipulation/#resizehttp://www.pixelbeat.org/docs/image_manipulation/#resizehttp://www.imagemagick.org/Usage/resize/http://www.pixelbeat.org/scripts/errnohttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/settings/.bashrchttp://www.pixelbeat.org/docs/power_of_the_default.htmlhttp://www.pixelbeat.org/scripts/ansi2html.sh


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Use 16:9 for widescreeninput

growisofs -dvd-compat -Z /dev/dvd -dvd-video dvdBurn DVD file system todisc

Unicode

python -c "import unicodedata as u; print u.name(unichr(0x2028))" Lookup a unicodecharacter

uconv-f utf8 -t utf8 -x nfcNormalizecombiningcharacters

printf '\300\200' | iconv -futf8 -tutf8 >/dev/null Validate UTF-8

printf 'TF8\n' | LANG=C grep --color=always '[^ -~]\+'Highlight non printableASCII chars in UTF-8

fc-match -s "sans:lang=zh"List font match order forlanguage and style

Development

gcc -march=native -E -v -&1|sed -n 's/.*-mar/-mar/p'Show autodetected gcctuning params. See alsogcccpuopt

for i in $(seq 4); do { [ $i = 1 ] && wgethttp://url.ie/6lko-qO-||./a.out; } | tee /dev/tty | gcc -xc - 2>/dev/null; done

Compile and execute Ccode from stdin

cpp -dM /dev/nullShow all predefinedmacros

echo "#include " | cpp -dN | grep "#define __USE_"Show all glibc featuremacros

gdb -tuiDebug showing sourcecode context inseparate

windowsExtended Attributes (Note you may need to (re)mount with "acl" or "user_xattr" options)

getfacl . Show ACLs for file

setfacl -m u:nobody:r .Allow a specific user toread file

setfacl -x u:nobody .Delete a specific user'srights to file

setfacl --default -m group:users:rw- dir/Set umask for a for aspecific dir

getcap fileShow capabilities for aprogram

setcap cap_net_raw+ep your_gtk_progAllow gtk program rawaccess to network

stat -c%C .Show SELinux contextfor file

chcon ... fileSet SELinux context forfile (see also restorecon)

getfattr -m- -d . Show all extended
http://manpages.ubuntu.com/manpages/dapper/en/man1/uconv.1.htmlhttp://manpages.ubuntu.com/manpages/dapper/en/man1/uconv.1.htmlhttp://manpages.ubuntu.com/manpages/dapper/en/man1/uconv.1.htmlhttp://www.pixelbeat.org/docs/unicode_utils/#normalizehttp://www.pixelbeat.org/docs/unicode_utils/#normalizehttp://www.pixelbeat.org/scripts/gcccpuopthttp://www.pixelbeat.org/scripts/gcccpuopthttp://www0.us.ioccc.org/2000/dhyang.chttp://www0.us.ioccc.org/2000/dhyang.chttp://www0.us.ioccc.org/2000/dhyang.chttp://www.pixelbeat.org/programming/debugger/#tuihttp://www.pixelbeat.org/programming/debugger/#tuihttp://www.pixelbeat.org/programming/debugger/#tuihttp://www.pixelbeat.org/programming/debugger/#tuihttp://www.pixelbeat.org/programming/debugger/#tuihttp://www.pixelbeat.org/programming/debugger/#tuihttp://www0.us.ioccc.org/2000/dhyang.chttp://www.pixelbeat.org/scripts/gcccpuopthttp://www.pixelbeat.org/docs/unicode_utils/#normalizehttp://manpages.ubuntu.com/manpages/dapper/en/man1/uconv.1.html


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attributes (includesselinux,acls,...)

setfattr -n "user.foo" -v "bar" .Set arbitrary userattributes

BASH specific

echo 123 | tee >(tr 1 a) | tr 1 bSplit data to 2 commands(using processsubstitution)

meldlocal_file

Documents

07-03 Linux Commands