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All commands from sorted by
Terminal - All commands - 12,143 results
dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
cd !$:h
2009-08-07 00:37:08
User: lingo
Functions: cd
25

Uses the last argument of the last executed command, and gets the directory name from it.

Use $!:t for the filename alone, without the dirname.

for I in $(mysql -e 'show databases' -s --skip-column-names); do mysqldump $I | gzip > "$I.sql.gz"; done
watch -n 1 nc localhost 80 '<<EOF GET / HTTP/1.1 Host: tux-ninja Connection: Close EOF'
2009-08-06 23:20:31
User: JustinHop
Functions: watch
1

Use the command watch, which is really hard to pass nested quotes to, and insert newlines where they are supposed to go in the HTTP request. that is after 1.1 after the host and two newlines at the end before the EOF.

i use this all day

what? no support for HEREDOCs on commandlinefu's interface? need more fu.

cat files.txt | xargs tar -cv | tar -x -c $DIR/
2009-08-06 22:55:21
User: lingo
Functions: cat tar xargs
0

If you want certain files out of a directory hierarchy, this will copy just the listed files, but will create the directory hierarchy in the new location ($DIR/)

ifconfig $devices | grep "inet addr" | sed 's/.*inet addr:\([0-9\.]*\).*/\1/g'
rm -d **/*(/^F)
2009-08-06 21:41:19
User: claytron
Functions: rm
Tags: find zsh glob
4

This command uses the recursive glob and glob qualifiers from zsh. This will remove all the empty directories from the current directory down.

The **/* recurses down through all the files and directories

The glob qualifiers are added into the parenthesis. The / means only directories. The F means 'full' directories, and the ^ reverses that to mean non-full directories. For more info on these qualifiers see the zsh docs: http://zsh.dotsrc.org/Doc/Release/Expansion.html#SEC87

find . -name "-help" -exec mv {} help.txt \;
sudo snmptrap -m ALL -v 2c -c public trapserver "" UCD-DEMO-MIB::ucdDemoPublic SNMPv2-MIB::sysLocation.0 s "Just here"
cp path/filename{,-$(date +%Y-%m-%d)}
2009-08-06 13:50:00
User: vutcovici
Functions: cp date
1

It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.

wget -O - http://checkip.dyndns.org|sed 's/[^0-9.]//g'
fetch -q -o - http://ipchicken.com | egrep -o '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}'
2009-08-06 11:57:44
User: spackle
Functions: egrep
-1

Same thing as above, just uses fetch and ipchicken.com

nmap -PN -d -p445 --script=smb-check-vulns --script-args=safe=1 IP-RANGES
curl -s 'http://checkip.dyndns.org' | sed 's/.*Current IP Address: \([0-9\.]*\).*/\1/g'
html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -d' ' -f4
2009-08-06 11:30:32
User: adonis28850
Functions: cut grep
-2

The same as the other user, but smarter, using -d and -f

ulimit -s 64
2009-08-06 10:40:25
User: ioggstream
Functions: ulimit
Tags: Linux ulimit
1

default stack size is 10M. This makes your multithread app filling rapidly your memory.

on my PC I was able to create only 300thread with default stack size.

Lower the default stack size to the one effectively used by your threads, let you create more.

ex. putting 64k I was able to create more than 10.000threads.

Obviously ...your thread shouldn't need more than 64k ram!!!

ldapmodify -Y "dn:uid=rob,dc=example.com" -g -R -J 2.16.840.1.113730.3.4.16 ...
html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -c21-36
curl -u yourusername:yourpassword -d status=?Your Message Here? https://twitter.com/statuses/update.xml
schedtool 1
2009-08-06 08:42:03
-1

Display information about the cores.

* sudo apt-get install schedtool

mencoder "mf://frame_*.bmp" -mf w=720:h=480:fps=30:type=bmp -ovc lavc -lavcopts vcodec=mpeg4 -o number_video.mp4
2009-08-06 06:59:49
0

Converts the batch of images to video.

*mencoder* required.

sudo cat /usr/share/icons/*/*/* > /dev/dsp
2009-08-06 03:12:27
User: 12345678
Functions: cat sudo
0

Plays the sound of the file, should sound like *some* kind of music, most files sound like static but some are really cool.

variations:

sudo cat /dev/sda > /dev/dsp sudo cat /dev/sda5 | aplay

Check out http://bbs.archlinux.org/viewtopic.php?id=70937 for more variations!

semi-dupe--like http://www.commandlinefu.com/commands/view/985/generate-white-noise but with different syntax and program.

sed "s:/old/direcory/:/new/directory/:" <file>
2009-08-06 00:37:45
Functions: sed
Tags: sed
8

Having to escape forwardslashes when using sed can be a pain. However, it's possible to instead of using / as the separator to use : .

I found this by trying to substitute $PWD into my pattern, like so

sed "s/~.*/$PWD/" file.txt

Of course, $PWD will expand to a character string that begins with a / , which will make sed spit out an error such as "sed: -e expression #1, char 8: unknown option to `s'".

So simply changing it to

sed "s:~.*:$PWD:" file.txt

did the trick.

find . -type f -print0 | xargs -0 -P 4 -n 40 grep -i foobar
2009-08-05 23:18:44
User: ketil
Functions: find grep xargs
4

xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.