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awk, bash, curl, find, grep, Linux, sed
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All commands from sorted by
Terminal - All commands - 12,454 results
ntpdate pool.ntp.org && hwclock --systohc && hwclock --adjust
2009-06-04 13:35:14
User: Weboide
Functions: hwclock
Tags: time sync ntp clock
5
Up
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Synchronize both your system clock and hardware clock and calculate/adjust time drift

Do not run this command if you already have ntpd running!

This needs to run as root, for example with sudo:

sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust

This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
export http_proxy=<user>:<pass>@<server>:<port> ftp_proxy=<user>:<pass>@<server>:<port>
2009-06-04 11:31:52
User: easter_egg
Functions: export
1
Up
Down
Configuring proxy client on terminal
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo ifconfig eth0 hw ether 00:01:02:03:04:05
2009-06-04 09:02:35
User: momitov
Functions: ifconfig sudo
Tags: MAC , Wireless, hack, change mac address
6
Up
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Change tha mac adresse

eth0 = the name of the interface

00:01:02:03:04:05 = the new mac adresse

the same thing for wireless card $ sudo iwconfig eth1 hw ether 00:01:02:03:04:05

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
recode UTF8..UTF-16LE linux-utf8-file.txt
2009-06-04 08:53:51
User: greppo
0
Up
Down
Convert file from UTF8 (no BOM) to UTF16 (with BOM)

Convert file from the UTF8 encoding used on Linux (has no "EF BB BF" byte order mark at the start) to the UTF-16 encoding used on Windows (has an "FF FE" byte order mark at the start).

Thanks to commenter: previous iconv command was the obsolete way to do it.

Comments (89) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
if [ -z $(echo $var | grep [0-9]) ]; then echo "NON NUMERIC"; fi
2009-06-04 07:41:26
User: AnusJenkins
Functions: echo grep
2
Up
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Non Numeric Check

use to execute a block of code only if $var is numeric

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lshw -html > hardware.html
2009-06-04 07:14:03
User: flart
28
Up
Down
Create a nifty overview of the hardware in your computer

After the command is done, open the html file in a browser

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -name "*jpg" -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR"
2009-06-03 22:08:48
User: vincentp
Functions: find grep
Tags: Image processing image photo jpeg corrupt
13
Up
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Find corrupted jpeg image files

Finds all corrupted jpeg files in current directory and its subdirectories. Displays the error or warning found.

The jpeginfo is part of the jpeginfo package in debian.

Should you wish to only get corrupted filenames, use cut to extract them :

find ./ -name *jpg -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR" | cut -d " " -f 1
Show sample output | Comments (72) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk '/match/{print NR}' file
2009-06-03 17:34:13
User: inof
Functions: awk
Tags: awk
5
Up
Down
Get line number of all matches in a file
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sed -n -e '1,/match/p'
2009-06-03 16:33:43
User: climatewarrior
Functions: sed
0
Up
Down
Delete all lines after the first match
Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
URL=http://svn.example.org/project; diff -u <(TZ=UTC svn -q log -r1:HEAD $URL | grep \|) <(TZ=UTC svn log -q $URL | grep \| | sort -k3 -t \|)
2009-06-03 14:26:55
User: sunny256
Functions: diff grep sort
Tags: bash svn
2
Up
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Find chronological errors or bad timestamps in a Subversion repository

Lists revisions in a Subversion repository with a timestamp that doesn't follow the revision numbering order. If everything is OK, nothing is displayed.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while (( $i != 0 )) { smbstatus; sleep 5; clear }
2009-06-03 13:26:30
User: unixmonkey4084
Functions: clear sleep
Tags: unix samba zsh
-4
Up
Down
See smbstatus all the time

See smbstatus Output within a 5 second interval (for monitoring smb access)

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find /var/log -type f -exec file {} \; | grep 'text' | cut -d' ' -f1 | sed -e's/:$//g' | grep -v '[0-9]$' | xargs tail -f
2009-06-03 09:47:08
User: mohan43u
Functions: cut file find grep sed tail xargs
Tags: tail
6
Up
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Monitor logs in Linux using Tail

Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option.

This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files.

Putting one alias in .profile will be more useful.

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for k in `git branch|perl -pe s/^..//`;do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k|head -n 1`\\t$k;done|sort -r
2009-06-03 08:25:00
User: brunost
Functions: echo head perl sort
Tags: bash git perl grep branches
16
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Show git branches by date - useful for showing active branches

Print out list of all branches with last commit date to the branch, including relative time since commit and color coding.

Show sample output | Comments (83) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f FILE | perl -pe 's/KEYWORD/\e[1;31;43m$&\e[0m/g'
2009-06-02 21:31:54
User: tuxifier
Functions: perl tail
17
Up
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coloured tail

tail with coloured output with the help of perl - need more colours? here is a colour table:

http://www.tuxify.de/?p=23

Show sample output | Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for i in `du --max-depth=1 $HOME | sort -n -r | awk '{print $1 ":" $2}'`; do size=`echo $i | awk -F: '{print $1}'`; dir=`echo $i | awk -F: '{print $NF}'`; size2=$(($size/1024)); echo "$size2 MB used by $dir"; done | head -n 10
2009-06-02 21:27:48
User: tuxifier
Functions: awk echo head sort
7
Up
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du disk top 10

fancy command line ncdu clone

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nslookup -q=txt -class=CHAOS version.bind NS.PHX5.NEARLYFREESPEECH.NET
2009-06-02 19:54:24
User: unixmonkey4063
Functions: nslookup
Tags: version
0
Up
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Check version of DNS Server
Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find /var/logs -name * | xargs tar -jcpf logs_`date +%Y-%m-%e`.tar.bz2
2009-06-02 19:48:47
User: unixmonkey4063
Functions: find tar xargs
Tags: find tarball
0
Up
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Archive every file in /var/logs
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find ~/Desktop/ \( -regex '.*/\..*' \) -print -exec rm -Rf {} \;
2009-06-02 19:45:06
User: unixmonkey4063
Functions: find rm
Tags: hidden find
-6
Up
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Search for all files that begin with . and delete them.
Show sample output | Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat somefile.css | awk '{gsub(/{|}|;/,"&\n"); print}' >> uncompressed.css
2009-06-02 15:51:51
User: lrvick
Functions: awk cat
Tags: awk compression css
1
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Uncompress a CSS file

Ever compress a file for the web by replacing all newline characters with nothing so it makes one nice big blob?

It is a great idea, however what about when you want to edit that file? ...Serious pain in the butt.

I ran into this today in that my only copy of a CSS file was "compressed" with no newlines.

I whipped this up and it converted back into nice human readable CSS :-)

It could be nicer, but it does the job.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
resolveip -s www.freshmeat.net
2009-06-02 14:25:53
User: ncaio
1
Up
Down
resolve hostname to IP our vice versa with less output

inverted version:

resolveip -s 216.34.181.xxx

freshmeat.net

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
2009-06-02 09:48:59
User: lxtips
Functions: head sed tail
Tags: sed lynx
-2
Up
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print random commandlinefu.com submission

ok I'm sure it's not pretty

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
date -d '1 day ago'; date -d '11 hour ago'; date -d '2 hour ago - 3 minute'; date -d '16 hour'
2009-06-01 10:41:56
User: LrdShaper
Functions: date
Tags: Date manipulation Linux find dates
5
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Get yesterday's date or a previous time

With this command you can get a previous or future date or time. Where can you use this? How about finding all files modified or created in the last 5 mins?

touch -t `echo $(date -d "5 minute ago" "+%G%m%d%H%M.%S")` me && find . -type f -newer me

List all directories created since last week?

touch -t `echo $(date -d "1 week ago" "+%G%m%d%H%M.%S")` me && find . -type d -cnewer me

I'm sure you can think of more ways to use it. Requires coreutils package.

Show sample output | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
postsuper -d ALL
2009-05-31 23:47:02
User: virtualshock
Tags: Postfix
2
Up
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Remove all mail in Postfix mail queue.
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while [ i != 0 ]; do sleep 1 | dialog --clear --gauge "Quality: " 0 0 $(cat /proc/net/wireless | grep $WIRELESSINTERFACE | awk '{print $3}' | tr -d "."); done
2009-05-31 16:09:23
User: ncaio
Functions: awk cat grep sleep tr
1
Up
Down
Check wireless link quality with dialog box

The variable WIRELESSINTERFACE indicates your wireless interface

Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pdfinfo Virtualization_A_Beginner_Guide.pdf | awk /Pages/
2009-05-31 15:45:38
User: ncaio
Functions: awk
7
Up
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Get pages number of the pdf file
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate