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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




All commands from sorted by
Terminal - All commands - 11,493 results
find . -type d -name '.svn' -print0 | xargs -0 rm -rdf
ssh-keygen -l -f [pubkey] | awk '{print $2}' | tr -ds ':' '' | egrep -ie "[a-f0-9]{32}"
tcpdump -nli eth0; tcpdump -nli eth0 src or dst w.x.y.z; tcpdump -nli eth0 port 80; tcpdump -nli eth0 proto udp
2009-02-05 17:41:55
User: jonty
Functions: tcpdump

At some point you want to know what packets are flowing on your network. Use tcpdump for this. The man page is obtuse, to say the least, so here are some simple commands to get you started.

-n means show IP numbers and don't try to translate them to names.

-l means write a line as soon as it is ready.

-i eth0 means trace the packets flowing through the first ethernet interface.

src or dst w.x.y.z traces only packets going to or from IP address w.x.y.z.

port 80 traces only packets for HTTP.

proto udp traces only packets for UDP protocol.

Once you are happy with each option combine them with 'and' 'or' 'not' to get the effects you want.

find . -name "*.py" | xargs wc -l
fsutil file createnew FILENAME filesize(inbytes)
2009-02-05 17:36:33
User: archlich
Functions: file

This command creates a file of arbitrary size in a windows environment.

ssh-keygen -i -f $sshkeysfile >> authorized_keys
PS1="\[\033[44;1;37m\]\u\[\033[0m\]@\h\\$ "
svn st | grep "^\?" | awk "{print \$2}" | xargs svn add $1
mount /path/to/file.iso /mnt/cdrom -oloop
2009-02-05 17:28:06
User: nerd65536
Functions: mount
Tags: mount iso

"-o loop" lets you use a file as a block device

gcc -Wall -Werror -o prog prog.c || rm -f prog.c
/bin/rpm -qf /etc/passwd /etc/issue /etc/httpd/conf/httpd.conf
export PS1='C:${PWD//\//\\\}>'
dump 0f - / | bzip -c9 | ssh user@host "cat > /home/user/root.dump.bz2"
2009-02-05 17:22:32
User: wwest4
Functions: dump ssh

...can do similar w/ tar, dd, xfsdump, e2fsdump, etc.

fuser [portnumber]/[proto]
2009-02-05 17:11:04
User: wwest4
Functions: fuser


fuser 25/tcp (see which pid is listening on smtp)

stty sane
du -hc *
ct find -avobs -nxname -element 'brtype(branch_name)' -print 2>/dev/null
///bin/true; exec java bsh.Interpreter "$0" "$@"
2009-02-05 17:00:05
User: chmx
Functions: exec

The two lines below are for a BeanShell script so it can be executed under Linux and Cygwin. Also, bsh.jar must be in the CLASSPATH environment variable, or in the jre/lib/ext/ directory of the JVM.

#! /bin/sh

///bin/true; exec java bsh.Interpreter "$0" "$@"

ls -dF `find . -maxdepth 1 \( -perm -1 -o \( -perm -10 -o -perm -100 \) \) -print`
2009-02-05 16:59:38
User: wam
Functions: ls

Does an 'ls' on just the files and directories in the current directory with an execute bit turned on. This version will list directories. Just tack on "-type f" to the start of the find to omit listing directories and list only files.

nano `which script`
2009-02-05 16:57:41
User: fzero

Substitute nano with your favorite editor, of course.

tac file.txt
2009-02-05 16:54:45
User: systemj
Functions: tac

Or "tail -r" on Solaris.

openssl ans1parse -inform DER < [priv key]
2009-02-05 16:54:19
User: wwest4

a pkcs8 key will have integer 00 at offset 4 and an rsaEncryption object at offset 9

openssl pkcs8 -inform DER -nocrypt -in [priv key] -out [pem priv key]
python -m smtpd -n -c DebuggingServer localhost:1025
2009-02-05 16:50:44
User: jemerick
Functions: python

This command will start a simple SMTP server listening on port 1025 of localhost. This server simply prints to standard output all email headers and the email body.