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Validate openssh key & print checksum
This is sample output - yours may be different.
1

ssh-keygen -l -f [pubkey] | awk '{print $2}' | tr -ds ':' '' | egrep -ie "[a-f0-9]{32}"

wwest4 · 2009-02-05 17:42:30 16
Getting started with 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.
This is sample output - yours may be different.
2

tcpdump -nli eth0; tcpdump -nli eth0 src or dst w.x.y.z; tcpdump -nli eth0 port 80; tcpdump -nli eth0 proto udp

jonty · 2009-02-05 17:41:55 16
Get line count for any file ending with extension recursively rooted at the current directory.
This is sample output - yours may be different.
2

find . -name "*.py" | xargs wc -l

rlotun · 2009-02-05 17:39:44 29
Create files of arbitrary size in Windows

This command creates a file of arbitrary size in a windows environment. Show Sample Output
This is sample output - yours may be different.
```
fsutil file createnew deleteme 1024
File C:\deleteme is created

C:\>dir deleteme
...
Directory of C:\
02/05/2009  12:33 PM             1,024 deleteme
               1 File(s)          1,024 bytes
               0 Dir(s)   8,777,101,312 bytes free
```
0

fsutil file createnew FILENAME filesize(inbytes)

archlich · 2009-02-05 17:36:33 21
Convert an ssh2 public key to openssh format
This is sample output - yours may be different.
0

ssh-keygen -i -f $sshkeysfile >> authorized_keys

wwest4 · 2009-02-05 17:32:02 30
add a little color to your prompt
This is sample output - yours may be different.
0

PS1="\[\033[44;1;37m\]\u\[\033[0m\]@\h\\$ "

elofland · 2009-02-05 17:29:18 25
Add all unversioned files to svn
This is sample output - yours may be different.
8

svn st | grep "^\?" | awk "{print \$2}" | xargs svn add $1

mk · 2009-02-05 17:28:53 31
Mount a .iso file in UNIX/Linux

"-o loop" lets you use a file as a block device
This is sample output - yours may be different.
46

mount /path/to/file.iso /mnt/cdrom -oloop

nerd65536 · 2009-02-05 17:28:06 33
Klingon programming; weak code must die
This is sample output - yours may be different.
-6

gcc -Wall -Werror -o prog prog.c || rm -f prog.c

devoid · 2009-02-05 17:26:51 19
Search for in which package the specified file is included.
This is sample output - yours may be different.
1

/bin/rpm -qf /etc/passwd /etc/issue /etc/httpd/conf/httpd.conf

salexkidd · 2009-02-05 17:24:28 193
Make bash look like DOS

Credit goes here: http://blag.xkcd.com/2008/12/03/some-lists/ Show Sample Output
This is sample output - yours may be different.
```
user@hostname:~$

becomes:

C:\home\user>
```
0

export PS1='C:${PWD//\//\\\}>'

nerd65536 · 2009-02-05 17:23:53 25
Dump root ext3 fs over ssh

...can do similar w/ tar, dd, xfsdump, e2fsdump, etc.
This is sample output - yours may be different.
5

dump 0f - / | bzip -c9 | ssh user@host "cat > /home/user/root.dump.bz2"

wwest4 · 2009-02-05 17:22:32 15
Resets a terminal that has been messed up by binary input
This is sample output - yours may be different.
1

reset

nerd65536 · 2009-02-05 17:18:48 19
find process associated with a port

e.g. fuser 25/tcp (see which pid is listening on smtp)
This is sample output - yours may be different.
13

fuser [portnumber]/[proto]

wwest4 · 2009-02-05 17:11:04 28
Reset terminal that has been buggered by binary input or similar
This is sample output - yours may be different.
5

stty sane

wwest4 · 2009-02-05 17:07:53 17
Display total Kb/Mb/Gb of a folder and each file
This is sample output - yours may be different.
1

du -hc *

eluis · 2009-02-05 17:04:21 18
Clearcase find branch
This is sample output - yours may be different.
-1

ct find -avobs -nxname -element 'brtype(branch_name)' -print 2>/dev/null

naseer · 2009-02-05 17:02:29 23
(Inside of a shell script) Make executable a BeanShell script under Linux/Cygwin

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 "$0" "$@"
This is sample output - yours may be different.
0

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

chmx · 2009-02-05 17:00:05 21
List just the executable files (or directories) in current directory

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.
This is sample output - yours may be different.
1

ls -dF `find . -maxdepth 1 $ -perm -1 -o \( -perm -10 -o -perm -100 $ \) -print`

wam · 2009-02-05 16:59:38 17
Edit any script executable by the user.

Substitute nano with your favorite editor, of course.
This is sample output - yours may be different.
-2

nano `which script`

fzero · 2009-02-05 16:57:41 19
cat a file backwards

Or "tail -r" on Solaris.
This is sample output - yours may be different.
8

tac file.txt

systemj · 2009-02-05 16:54:45 25
Identify a PKCS#8 Private Key

a pkcs8 key will have integer 00 at offset 4 and an rsaEncryption object at offset 9
This is sample output - yours may be different.
-1

openssl ans1parse -inform DER < [priv key]

wwest4 · 2009-02-05 16:54:19 18
Convert a PKCS#8 private key to PEM format
This is sample output - yours may be different.
-1

openssl pkcs8 -inform DER -nocrypt -in [priv key] -out [pem priv key]

wwest4 · 2009-02-05 16:52:34 20
python smtp server

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.
This is sample output - yours may be different.
76

python -m smtpd -n -c DebuggingServer localhost:1025

jemerick · 2009-02-05 16:50:44 87
Turn /path/to/dir and subdirectories into a project tree

changes group ownership of all files/dirs in /path/to/dir to a project group [projgroup] and then gives the sgid bit to directories in that tree - all subsequently created files will inherit [projgroup]'s gid.
This is sample output - yours may be different.
0

chgrp -R [projgroup] ; find /path/to/dir -type d -exec chmod g+s {} \;

wwest4 · 2009-02-05 16:49:24 17
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Swap the two last arguments of the current command line

Say you just typed a long command like this: $ rsync -navupogz --delete /long/path/to/dir_a /very/long/path/to/dir_b but you really want to sync dir_b to dir_a. Instead of rewriting all the command line, just type followed by , and your command line will read $ rsync -navupogz --delete /very/long/path/to/dir_b /long/path/to/dir_a

Creating ISO Images from CDs/DVDs

create an iso from your cd/dvd-rom device . You need to umount /dev/cdrom before using the cli

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Get a qrcode for a given string

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

Number of files in a SVN Repository

This command will output the total number of files in a SVN Repository.

add all files not under version control to repository

With the force options the same results can be achieved

Print out a man page

man -t manpagename gives a postscript version of said man page. You then pipe it to ls, and assuming you have cups set up, it prints in your default printer.

Install pip with Proxy

Installs pip packages defining a proxy

Sprunge.us - CLI alternative to PasteBin.com

NAME sprunge: command line pastebin: SYNOPSIS | curl -F 'sprunge=

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