Commands using cat | commandlinefu.com

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Terminal - Commands using cat - 441 results

cat infile | while read str; do echo "$((++i)) - $str" ; done;

2009-12-09 14:05:09

User: glaudiston

Functions: cat echo read

-1

Up
Down

prints line numbers

Yep, is hard, but is a way more flexible using pipe.

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

cat -n

2009-12-08 16:35:55

User: putnamhill

Functions: cat

Tags: cat

Up
Down

prints line numbers

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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>

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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 [email protected] -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.

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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
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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

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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.

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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..

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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.

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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

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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

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cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" [email protected]

2009-10-19 20:38:37

User: slashdot

Functions: cat mailx

Tags: Security GPG Encryption email

Up
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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.

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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.

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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

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cat ~/SortedFile.txt | perl -wnl -e [email protected]=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r][email protected][$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 :-)

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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

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cat filename | uuencode filename | mail -s "Email subject" [email protected]

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

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cat filename | mail -s "Email subject" [email protected]

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.

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cat *.sql | mysql <db_name>

2009-09-15 17:28:35

User: rehanift

Functions: cat

Up
Down

Execute all SQL files in a directory

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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
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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.

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