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May 19, 2015 - A Look At The New Commandlinefu
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Commands using cat from sorted by
Terminal - Commands using cat - 445 results
(bzcat BZIP2_FILES && cat TEXT_FILES) | grep -E "Invalid user|PAM" | grep -o -E "from .+" | awk '{print $2}' | sort | uniq >> /etc/hosts.deny
2010-01-03 04:41:51
User: jayhawkbabe
Functions: awk cat grep sort uniq

Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.

ps aux | grep [h]ttpd | cat -n
2009-12-17 20:45:44
User: putnamhill
Functions: cat grep ps
Tags: cat

If you're on a system that doesn't have nl, you can use cat -n.

cat ~/.ssh/id_rsa.pub | ssh <remote_host> "xargs --null echo >> ~/.ssh/authorized_keys"
2009-12-17 15:12:11
User: koushik
Functions: cat ssh

Well its just appending your public key to the remote hosts authorized_keys, but can get messy logging in and out

cat infile | while read str; do echo "$((++i)) - $str" ; done;
2009-12-09 14:05:09
User: glaudiston
Functions: cat echo read

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

cat -n
cat </dev/tcp/time.nist.gov/13
2009-12-03 21:40:14
User: drewk
Functions: cat
Tags: cat tcp


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
cat ~/.viminfo | sed -n '/^:[0-9]\+,\([0-9]\+\|\$\)s/p'
2009-11-29 01:54:57
User: jyf
Functions: cat sed

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
[ $1 == "client" ] && hostname || cat $0 | ssh $1 /bin/sh -s client
2009-11-25 22:24:31
User: a8ksh4
Functions: cat hostname ssh

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

hosta> cat myScript.sh


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

hosta> myScript.sh hostb



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

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.

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
2009-11-20 14:53:26
User: taliver
Functions: awk cat head printf sort tr uniq

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
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

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.

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]};
cat > list -
2009-10-29 20:20:11
Functions: cat

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

TIMEUNIT=$( cat a | grep -n "timescale" | awk -F ":" '{ print $1 } ' )
teste.txt < cut -d : -f 1,5 /etc/passwd | tr : \\t | tr a-z A-Z | cat teste.txt
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

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.

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

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

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

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

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

cat -n file or cat -b file
2009-09-24 12:18:40
User: eastwind
Functions: cat file

cat -n file : number all line

cat -b file : number only non empty line

see man cat