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Commands using cat from sorted by
Terminal - Commands using cat - 434 results
cat /dev/urandom | pv -L 3m | dd bs=1M count=100 iflag=fullblock > /dev/null
2012-07-29 00:42:16
User: bugmenot
Functions: cat dd
6

This example will close the pipe after transferring 100MB at a speed of 3MB per second.

cat ~/.ssh/id_rsa.pub | ssh tester@10.2.6.10 "mkdir -p ~/.ssh; cat >> ~/.ssh/authorized_keys; chmod 600 ~/.ssh/authorized_keys"
2012-07-18 04:41:55
Functions: cat ssh
0

chmod authorized_keys so you don't get "Authentication refused: bad ownership or modes for file /home/user/.ssh/authorized_keys"

cat ~/.ssh/id_rsa.pub | ssh tester@10.2.6.10 "mkdir -p ~/.ssh; cat >> ~/.ssh/authorized_keys; chmod 600 ~/.ssh/authorized_keys"
2012-07-18 04:41:54
Functions: cat ssh
0

chmod authorized_keys so you don't get "Authentication refused: bad ownership or modes for file /home/user/.ssh/authorized_keys"

cat .ssh/id_rsa.pub | ssh user@server 'cat >> ~/.ssh/authorized_keys2'
2012-07-12 15:42:10
User: er0k
Functions: cat ssh
-4

for passwordless login

cat ~/.bash_history | perl -lane 'if($F[0] eq "sudo"){$hash{$F[1]}++}else{$hash{$F[0]}++};$all++;END {@top = map {[$_, $hash{$_}]} sort {$hash{$b}<=>$hash{$a}} keys %hash;printf("%10s%10d%10.2f%%\n", $_->[0],$_->[1],$_->[1]/$all*100) for @top[0..9]}'
cat file.txt > /dev/null
2012-06-26 18:34:12
User: ankush108
Functions: cat
0

This will be very helpful when you are debugging shell scripts, where

you don?t want to display the echo statement and interested in only

looking at the error messages. Similarly use 2> to supress error messages

diff <(ssh user@host cat /path/to/remotefile) /path/to/localfile
watch -n 1 cat /proc/net/wireless
2012-06-07 10:38:21
User: cantormath
Functions: cat watch
-3

Values will depend on the driver and the hardware specifics, so you need to refer to your driver documentation for proper interpretation of those values.

cat urls.txt | wget -i- -T 10 -t 3 --waitretry 1
cat urls.txt | xargs -n1 curl -O --max-time 10 --retry 3 --retry-delay 1
cat /var/log/nginx/access.log | grep -oe '^[0-9.]\+' | perl -ne 'system("geoiplookup $_")' | grep -v found | grep -oe ', [A-Za-z ]\+$' | sort | uniq -c | sort -n
2012-05-08 13:28:25
User: theist
Functions: cat grep perl sort uniq
Tags: sort uniq geoip
-1

Per country GET report, based on access log. Easy to transform to unique IP

while true; do sudo cat /dev/input/mouse0|read -n1;streamer -q -o /tmp/cam.jpeg -s 640x480 > /dev/null 2>&1; sleep 10;done
2012-04-22 01:51:30
User: SQUIIDUX
Functions: cat read sleep sudo
Tags: cat streamer
4

This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it.

Ideas:

Use in conjunction with a dropbox type application to see who is using your computer

Use /dev/input/mice if /dev/input/mouse* doesn't work

Use the bones of this to make a simple screensaver

while true; do iptables -nvL > /tmp/now; diff -U0 /tmp/prev /tmp/now > /tmp/diff; clear; cat /tmp/diff; mv /tmp/now /tmp/prev; slee p 1; done
2012-04-15 00:02:33
Functions: cat diff iptables mv
0

this alternative shows the differences as they occur so that they are made plain

yes "" | cat -n | awk '{print "S=`echo All work and no play makes Jack a dull boy. | cut -c",($1 - 1) % 43 + 1 "`;echo -n \"$S\";seq 500000 > /dev/null"}'| bash
sed G input.txt | cat -s
cat z.log | perl -ne 'BEGIN{ print "DATE;RATE\n"; } /\[(\d.*)\]/ && print $1; /CURRENT RATE: +(\S+) msg.*/ && print ";" .$1 . "\n"; '
2012-04-03 13:52:20
User: hute37
Functions: cat perl
1

extract data in multiline blocks of data with perl pattern matching loop

pdftk A=1.pdf B=2.pdf C=3.pdf cat C A output CA.pdf
pdftk 1.pdf 2.pdf cat output 12.pdf
cat > file_name
2012-03-27 11:38:09
Functions: cat
-2

Write script or commands in notepad/Editplus/MS word etc, copy the contents, type the above command and click on enter now, paste by right click-ing the mouse. Entire contents in the clip-board gets pasted now again click on Enter to go to new line/next line. Press Ctrl+D to close/save the file. Not always required to vi to create a new file.

wget -q ip.nu && cat index.html
find . -type f -name "*.*" -exec cat {} > totalLines 2> /dev/null \; && wc -l totalLines && rm totalLines
ps h --ppid $(cat /var/run/apache2.pid) | awk '{print"-p " $1}' | xargs sudo strace
2012-03-21 01:59:41
Functions: awk cat ps sudo xargs
3

Like the original version except it does not include the parent apache process or the grep process and adds "sudo" so it can be run by user.

for a in $(cat sample.txt); do echo "${#a} $a";done|sort -n
for a in $(cat sample.txt); do echo "$(wc -m<<<$a) $a";done|sort -n
2012-03-15 08:51:42
User: knoppix5
Functions: cat echo sort
0

optionally you can add

|cut -d' ' -f2|uniq

to the end of the command line.

x=1024; y=32768; cat <(echo -e "P5\n$x $y\n255\n") <(dd if=/dev/sda1 bs=$x count=$y) > sda1.pgm
2012-03-06 03:09:16
User: adeverteuil
Functions: cat dd echo
Tags: dd images pnm pgm
1

Keep width to a power of 2 to see patterns emerge. 512 is good. So is 4096 for huge maps.

PNM headers are super basic.

http://netpbm.sourceforge.net/doc/pbm.html