Commands using cat | commandlinefu.com

Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

OpenID

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands using cat

Hide

News

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.

Hide

Functions

Hide

Credits

Site by David Winterbottom (user root).

Terminal - Commands using cat - 417 results

cat -n

2009-12-08 16:35:55

User: putnamhill

Functions: cat

Tags: cat

Up
Down

prints line numbers

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat </dev/tcp/time.nist.gov/13

2009-12-03 21:40:14

User: drewk

Functions: cat

Tags: cat tcp

Up
Down

Get the time from NIST.GOV

The format is JJJJJ YR-MO-DA HH:MM:SS TT L DUT1 msADV UTC(NIST) OTM

and is explained more fully here: http://tf.nist.gov/service/acts.htm

cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 10 | sed 1q

2009-12-01 09:09:56

User: gnuyoga

Functions: cat fold sed tr

Up
Down

generate random password

generate password

cat ~/.viminfo | sed -n '/^:[0-9]\+,$[0-9]\+\|\$$s/p'

2009-11-29 01:54:57

User: jyf

Functions: cat sed

Up
Down

show how many regex you use in your vim today

i want to count how many regex code i have used in vim in a long time

so i make a directory in svn host and post record to this directory

of course i dont want to post manually so i worte a script to do that

and this is the core thing to do

while true; do wget -r -l1 --no-clobber -A.txt http://911.wikileaks.org/files/index.html; done; cat *.txt | grep pass

2009-11-26 23:38:44

User: Cowboy

Functions: cat grep wget

-5

Up
Down

Passwords from 9/11 tragedy pager intercepts (Yeah! Plain text! From wikileaks.net)

http://www.reddit.com/r/reddit.com/comments/a7xpt/conspiracy_theories_commence_wikileaks_to_release/

[ $1 == "client" ] && hostname || cat $0 | ssh $1 /bin/sh -s client

2009-11-25 22:24:31

User: a8ksh4

Functions: cat hostname ssh

Up
Down

Script executes itself on another host with one ssh command

Now put more interesting stuff on the script in replacement of hostname, even entire functions, etc, and stuff.

hosta> cat myScript.sh

#!/bin/sh

[ $1 == "client" ] && hostname || cat $0 | ssh $1 /bin/sh -s client

hosta> myScript.sh hostb

hostb

hosta>

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat /var/log/httpd/access_log | grep q= | awk '{print $11}' | awk -F 'q=' '{print $2}' | sed 's/+/ /g;s/%22/"/g;s/q=//' | cut -d "&" -f 1 | mail youremail@isp.com -s "[your-site] search strings for `date`"

2009-11-22 03:03:06

User: isma

Functions: awk cat grep sed strings

Tags: cat bash sed awk grep cut mail httpd access_log

-2

Up
Down

Checks apache's access_log file, strips the search queries and shoves them up your e-mail

It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

This is sample output - yours may be different.

$ cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

  60 .+-----+------+------+------+-------+------+------+------+------+-----++
     +      +      +      +      +       +      +      +      +      +      +
     |                                                                      |
  50 ++                                                                    ++
     |                                                                      |
     |.                                                                     |
     |.                                                                     |
  40 ++                                                                    ++
     |                                                                      |
     | ..                                                                   |
  30 ++                                                                    ++
     |   .                                                                  |
     |                                                                      |
  20 ++  ..                                                                ++
     |     ..                                                               |
     |       ..                                                             |
     |         ...                                                          |
  10 ++           ....                                                     ++
     |                ...............                                       |
     +      +      +      +      +   .......................................+
   0 ++-----+------+------+------+-------+------+------+------+------+-----++
     0      10     20     30     40      50     60     70     80     90    100

2009-11-20 14:53:26

User: taliver

Functions: awk cat head printf sort tr uniq

Up
Down

Plot frequency distribution of words from files on a terminal.

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.

pdftk 1.pdf 2.pdf 3.pdf cat output 123.pdf

2009-11-10 10:07:37

User: eastwind

Functions: cat

Up
Down

Merge Two or More PDFs into a New Document

require the pdftk package

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat /dev/hda > ~/hda.iso

2009-11-09 15:44:53

User: mvrilo

Functions: cat

Tags: cat hard disk harddisk

-9

Up
Down

Make an iso file out of your entire hard drive

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat /path/to/some/file.txt | tee /dev/pts/0 | wc -l

2009-11-07 22:24:28

User: atoponce

Functions: cat tee wc

Tags: tee

Up
Down

Both view and pipe the file without saving to disk

This is a cool trick to view the contents of the file on /dev/pts/0 (or whatever terminal you're using), and also send the contents of that file to another program by way of an unnamed pipe. All the while, you've not bothered saving any extra data to disk, like you might be tempted to do with sed or grep to filter output.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

exec 3<>/dev/tcp/whatismyip.com/80; echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" >&3; a=( $(cat <&3) ); echo ${a[${#a[*]}-1]};

2009-11-03 21:57:00

User: yaccovs

Functions: cat echo exec

Tags: Network IP external

-3

Up
Down

Get your external IP address

bash neto..

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat > list -

2009-10-29 20:20:11

User: servermanaged

Functions: cat

Up
Down

Quick notepad

Quick write some notes to a file with cat. Ctrl+C when you have finish.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

TIMEUNIT=$( cat a | grep -n "timescale" | awk -F ":" '{ print $1 } ' )

2009-10-27 18:01:26

User: conradojr

Functions: awk cat grep

Tags: awk grep

-3

Up
Down

Get a text on a position on the file and store in a variable with a specific separator

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

teste.txt < cut -d : -f 1,5 /etc/passwd | tr : \\t | tr a-z A-Z | cat teste.txt

2009-10-20 14:53:38

User: osvaldofilho

Functions: cat cut tr

-12

Up
Down

List system's users

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" user@email.com

2009-10-19 20:38:37

User: slashdot

Functions: cat mailx

Tags: Security GPG Encryption email

Up
Down

Quickly Encrypt a file with gnupg and email it with mailx

This is a quick and easy way of encrypting files in a datastream, without ever really creating an output file from gpg. Useful with cron also, when file(s) have to be sent based on a set schedule.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done

2009-10-12 12:49:18

User: Sunng

Functions: cat head rm

-1

Up
Down

remove the last line of all html files in a directory

Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done

2009-10-06 07:09:23

User: opexxx

Functions: cat printf read

Up
Down

Bashbuiltin printf

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat ~/SortedFile.txt | perl -wnl -e '@f=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'

2009-09-24 15:42:43

User: drewk

Functions: cat perl

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-

host A: cat /proc/dev/ttyS0 host B: echo hello > /dev/ttyS0

2009-09-24 13:22:23

User: flart

Functions: cat echo host

Up
Down

Test a serial connection

If the connection works you should see a "hello" on host A. If not: check your cabeling etc :-)

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat -n file or cat -b file

2009-09-24 12:18:40

User: eastwind

Functions: cat file

Up
Down

number the line of a file

cat -n file : number all line

cat -b file : number only non empty line

see man cat

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat filename | uuencode filename | mail -s "Email subject" user@example.com

2009-09-21 04:13:50

User: amaymon

Functions: cat mail uuencode

Tags: cat mail

Up
Down

Send a local file via email

uuencode the file to appear as an attachment

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat filename | mail -s "Email subject" user@example.com

2009-09-20 01:38:23

User: topher1kenobe

Functions: cat mail

Tags: cat mail

Up
Down

Send a local file via email

This just reads in a local file and sends it via email. Works with text or binary. *Requires* local mail server.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat *.sql | mysql <db_name>

2009-09-15 17:28:35

User: rehanift

Functions: cat

Up
Down

Execute all SQL files in a directory

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat /var/lib/dpkg/info/*.list > /tmp/listin ; ls /proc/*/exe |xargs -l readlink | grep -xvFf /tmp/listin; rm /tmp/listin

2009-09-09 18:09:14

User: kamathln

Functions: cat grep ls readlink rm xargs

Tags: Debian find dpkg

Up
Down

Find running binary executables that were not installed using dpkg

This helped me find a botnet that had made into my system. Of course, this is not a foolproof or guarantied way to find all of them or even most of them. But it helped me find it.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

‹ First < 10 11 12 13 14 > Last ›