Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

OpenID
or
Sign in Register

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

UpGuard checks and validates configurations for every major OS, network device, and cloud provider.
Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!
Hide

Top Tags


awk, bash, curl, find, grep, Linux, sed
Hide

Functions

Commands using tail from sorted by
Terminal - Commands using tail - 244 results
ps axo rss,comm,pid | awk '{ proc_list[$2]++; proc_list[$2 "," 1] += $1; } END { for (proc in proc_list) { printf("%d\t%s\n", proc_list[proc "," 1],proc); }}' | sort -n | tail -n 10
2010-03-03 16:41:05
User: d34dh0r53
Functions: awk ps sort tail
5
Up
Down
Top ten (or whatever) memory utilizing processes (with children aggregate)

This command loops over all of the processes in a system and creates an associative array in awk with the process name as the key and the sum of the RSS as the value. The associative array has the effect of summing a parent process and all of it's children. It then prints the top ten processes sorted by size.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"
2010-02-26 20:29:45
User: d34dh0r53
Functions: awk echo grep head tail
6
Up
Down
Print Memory Utilization Percentage For a specific process and it's children

Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -n 50 -f /var/log/apache2/access_log /var/log/apache2/error_log
2010-02-21 14:45:44
User: warlock
Functions: tail
5
Up
Down
tail: watch a filelog

-f file(s) to be monitorized

-n number of last line to be printed on the screen

in this example, the content of two files are displayed

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find /path/to/dir -type f -printf "%T@|%p\n" 2>/dev/null | sort -n | tail -n 1| awk -F\| '{print $2}'
2010-02-04 15:13:27
User: glennie
Functions: awk find sort tail
Tags: bash find files recursive
2
Up
Down
A function to find the newest file in a directory
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f /var/log/apache2/access.log | awk -W interactive '!x[$1]++ {print $1}'
2010-01-12 15:23:03
User: pykler
Functions: awk tail
Tags: apache2 ip address access_log
1
Up
Down
Print unique ipaddresses as they come in from Apache Access Log File

Prints the unique IP Addresses as they arrive from an Apache `access.log` file.

The '-W interactive' tells awk to start writing to stdout immediately and not buffer the output.

This command builds on the uniq lines without sorting command (http://www.commandlinefu.com/commands/view/4389/remove-duplicate-entries-in-a-file-without-sorting.)

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find /home/bubo/ -type f \( -iname \*.jpg -print0 , -iname \*.png -print0 , -iname \*gif -print0 \) | du -cm --files0-from - | tail -1
2009-12-25 16:21:46
User: bubo
Functions: du find tail
0
Up
Down
show how much diskspace all images in a given directory need
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
watch 'dmesg | tail -15'
2009-12-20 02:00:05
User: Heoa
Functions: tail watch
-1
Up
Down
Monitor the Kernel Ring Buffer

Useful with new unknown devices or just monitoring, probably useful for the sysadmin. Updates every 2 seconds. More here: http://linuxclisecurity.blogspot.com/2009/12/monitor-kernel-ring-buffer.html.

Comments (71) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
zcat access_log.*.gz | awk '{print $7}' | sort | uniq -c | sort -n | tail -n 20
2009-12-11 09:36:30
User: tkb
Functions: awk sort tail uniq zcat
Tags: log apache zcat analysis
4
Up
Down
Analyse compressed Apache access logs for the most commonly requested pages
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail $0 >> $0
2009-12-07 12:33:41
User: yooreck
Functions: tail
Tags: dd df
1
Up
Down
Fill up disk space (for testing)

Put into some file. No special purpouse, just for fun...

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
git diff --stat `git log --author="XXXXX" --since="12 hours ago" --pretty=oneline | tail -n1 | cut -c1-40` HEAD
2009-11-04 01:41:33
User: askedrelic
Functions: cut diff tail
3
Up
Down
Figure out your work output for the day

Figures out what has changed in the last 12 hours.

Change the author to yourself, change the time since to whatever you want.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" | nc whatismyip.com 80 | tail -n1
2009-11-03 15:18:20
User: Marko
Functions: echo tail
Tags: Network IP external
-4
Up
Down
Get your external IP address
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps -eo user,pcpu,pmem | tail -n +2 | awk '{num[$1]++; cpu[$1] += $2; mem[$1] += $3} END{printf("NPROC\tUSER\tCPU\tMEM\n"); for (user in cpu) printf("%d\t%s\t%.2f\t%.2f\n",num[user], user, cpu[user], mem[user]) }'
2009-10-29 12:49:01
User: georgz
Functions: awk ps tail
7
Up
Down
cpu and memory usage top 10 under Linux

The original version gives an error, here is the correct output

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -F file | egrep --color 'pattern|$'
2009-10-16 04:01:14
User: sklm
Functions: egrep file tail
Tags: color
6
Up
Down
tail, with specific pattern colored
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f file | egrep --color=always $\|PATTERN
2009-10-15 13:08:30
User: sitaram
Functions: egrep file tail
Tags: color
-2
Up
Down
tail, with specific pattern colored

but you can't see the colors in that sample output :(

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f FILE | grep --color=always KEYWORD
2009-10-15 06:54:45
User: dennisw
Functions: grep tail
Tags: color
0
Up
Down
colored tail
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
2009-10-12 14:57:54
User: pykler
Functions: bash cut du echo read sed tail tr xargs
Tags: Debian wajig
4
Up
Down
List your largest installed packages.

Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the

| sort -rn

which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side

Also you may need to run this as root as some files can only be checked by du if you can read them ;)

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
wget -q -O - 'http://wap.weather.gov.hk/' | sed -r 's/<[^>]+>//g;/^UV/q' | tail -n4
2009-09-25 02:36:46
User: dakunesu
Functions: sed tail wget
-1
Up
Down
get Hong Kong weather infomation from HK Observatory

"get Hong Kong weather infomation from HK Observatory

From Hong Kong Observatory wap site ;)"

other one showed alot of blank lines for me

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($t +=$1) && printf "%02d:%02d:%02d\n",$t/3600,$t/60%60,$t%60' | tail -n 1
2009-09-24 15:50:39
User: syssyphus
Functions: find perl printf tail xargs
Tags: video audio mplayer perl find
10
Up
Down
Get the total length of all video / audio in the current dir (and below) in H:m:s

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

Comments (80) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lsof -P -i -n | cut -f 1 -d " "| uniq | tail -n +2
2009-09-19 21:23:54
User: edo
Functions: cut tail uniq
Tags: bash grep lsof internet
31
Up
Down
Show apps that use internet connection at the moment.

show only the name of the apps that are using internet

Show sample output | Comments (75) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ls -t | tail +6 | xargs rm
2009-09-16 06:33:07
User: negyvenot
Functions: ls tail xargs
Tags: ls
3
Up
Down
Delete all but the latest 5 files

yes 6 (tail from 6th line)

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i x86_64 |nl | tail -1 | cut -f1 -f3; file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i "mach-o object i386" |nl | tail -1 | cut -f1 -f3
2009-09-11 16:43:27
User: digitalshadow
Functions: cut file grep nl tail
-2
Up
Down
How far is Mac OS X 10.6 from 64-bit?

Not as far off as you thought, now is it?

-mac fanboy

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
2009-09-08 08:25:45
User: karpoke
Functions: awk find tail wc xargs
Tags: awk find wc
0
Up
Down
Make a statistic about the lines of code

This is really fast :)

time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'

204753

real 0m0.191s

user 0m0.068s

sys 0m0.116s

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ls -lct /etc/ | tail -1 | awk '{print $6, $7, $8}'
2009-09-04 16:52:50
User: peshay
Functions: awk ls tail
5
Up
Down
When was your OS installed?

shows also time if its the same year or shows year if installed before actual year and also works if /etc is a link (mac os)

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i x86_64 |nl |tail -1 |cut -f1 -f3 && file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -v x86_64 |nl |tail -1 |cut -f1 -f3
2009-09-03 14:28:02
User: commandlinefu
Functions: cut file grep nl tail
-1
Up
Down
How far is Mac OS X 10.6 from 64-bit?

Next time you see a mac fanboy bragging about 64-bitness of 10.6 give him this so he might sh?

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ls -lct /etc | tail -1 | awk '{print $6, $7}'
2009-09-03 10:26:37
User: MrMerry
Functions: awk ls tail
10
Up
Down
When was your OS installed?

Show time and date when you installed your OS.

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate