Commands by forcefsck

Commands by forcefsck (8)

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Find out the installation time of a linux system (when installed in a ext2/3/4 file system)

Find out the earliest installation time of a linux system by getting the / filesystem creation time. This example is only valid the os is installed on an ext2/3/4 filesystem.
This is sample output - yours may be different.
0

tune2fs -l $(df -P / | awk 'NR==2 {print $1}') | sed -n 's/^.*created: *//p'

forcefsck · 2012-05-31 12:12:35 0
encode/decode HTML entities

For reverse, there's asc2xml asc2xml < entitiesfile > utf8file They come as a part of the html-xml-utils debian package. PS. Tried to submit sample data, but the site autoconverted the non ascii to html entities. So a bit of imagination is needed. Show Sample Output
This is sample output - yours may be different.
```
$ echo "foo somegreekchars bar" | xml2asc
foo &#945;&#946;&#947;&#948; bar

$ echo "foo &#945;&#946;&#947;&#948; bar" | asc2xml 
foo somegreekchars bar
```
-3

xml2asc < inputfile > outputfile

forcefsck · 2011-02-23 12:22:18 1
Rename files in a directory in an edited list fashion

just an alternative to #7818 Show Sample Output
This is sample output - yours may be different.
```
Rename file: 1one
To: 1one.txt
`1one' -> `1one.txt'
Rename file: 2two
To: one plus one
`2two' -> `one plus one'
Rename file: 3three
To: 3three
Rename file: 4four
To: 2 x 2
`4four' -> `2 x 2'
Rename file: 5five
To: 5five.avi
`5five' -> `5five.avi'
```
0

exec 3<&0; ls -1N | while read a; do echo "Rename file: $a"; read -e -i "$a" -p "To: " b <&3 ; [ "$a" == "$b" ] || mv -vi "$a" "$b"; done

forcefsck · 2011-02-08 21:21:39 0
Display any udp/tcp connections by process name or by process id

Where COMMAND is the process(es) name. I prefer to get all states but you may add ESTABLISHED in the grep regex. lsof -c apache2 | egrep -o 'TCP.*ESTABLISHED.*$' -nP flags are optional and UDP is irrelevant for established connections Similar but using the process id: lsof -nP -p PID | egrep -o '(TCP|UDP).*$' Show Sample Output
This is sample output - yours may be different.
```
$ lsof -nP -c apache2 | egrep -o 'TCP.*$' | sort -u
TCP 192.168.0.2:443->192.168.0.136:3373 (ESTABLISHED)
TCP 192.168.0.2:443->192.168.0.137:11127 (ESTABLISHED)
TCP 192.168.0.2:443->192.168.0.137:11153 (ESTABLISHED)
TCP *:443 (LISTEN)
TCP *:80 (LISTEN)

$ lsof -p 17279|egrep -o '(TCP|UDP).*$'
TCP 127.0.0.1:32434 (LISTEN)
UDP *:32435 
```
0

lsof -nP -c COMMAND | egrep -o '(TCP|UDP).*$' | sort -u

forcefsck · 2011-01-25 12:04:13 0

network throughput test

On the machine acting like a server, run: iperf -s On the machine acting like a client, run: iperf -c ip.add.re.ss where ip.add.re.ss is the ip or hostname of the server. Show Sample Output

iperf -s

forcefsck · 2011-01-24 07:58:38 0

String to binary

Cool but useless. Show Sample Output
This is sample output - yours may be different.
```
perl -nle 'printf "%0*v8b\n"," ",$_;'
hello
01101000 01100101 01101100 01101100 01101111
world
01110111 01101111 01110010 01101100 01100100
!
00100001
```
6

perl -nle 'printf "%0*v8b\n"," ",$_;'

forcefsck · 2011-01-21 09:20:54 2
tcptraceroute alternative for udp packets

-T = traceroute -V = verbose --tr-stop = exit when target is reached -n = don't do reverse lookups (faster) -2 = udp -p 53 = destination port 53 (dns), change to your needs Useful when trying to debug a network with complex routing rules and/or multiple gateways.
This is sample output - yours may be different.
0

sudo hping3 -TV --tr-stop -n -2 -p 53 ns1.server.tld

forcefsck · 2011-01-14 10:12:37 0
Generate random valid mac addresses

Shorter and more straightforward. Also in perl: perl -e 'print join(":", map { sprintf "%0.2X",rand(256) }(1..6))."\n"'
This is sample output - yours may be different.
2

for i in {1..6}; do printf "%0.2X:" $[ $RANDOM % 0x100 ]; done | sed 's/:$/\n/'

forcefsck · 2010-12-07 19:26:58 0

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Edit a file on a remote host using vim

Reconnect to screen without disconnecting other sessions

Have your screen session running in multiple places. (warning, things start to look weird if the terminal windows have different dimensions)

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

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Generate an XKCD #936 style 4 word password

4 random words are better than one obfuscated word http://xkcd.com/936/

find and grep Word docs

Find Word docs by filename in the current directory, convert each of them to plain text using antiword (taking care of spaces in filenames), then grep for a search term in the particular file. (Of course, it's better to save your data as plain text to make for easier grepping, but that's not always possible.) Requires antiword. Or you can modify it to use catdoc instead.

list block devices

Shows all block devices in a tree with descruptions of what they are.

Erase CD RW

HourGlass

Displays an animated hourglass for x amount of seconds

drop first column of output by piping to this

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