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Commands using cat from sorted by
Terminal - Commands using cat - 416 results
logs=$(find . -name *.log);for log in $logs; do cat /dev/null > $log;done
2009-03-04 10:05:48
Functions: cat find
-5

This find files of name like *.log and truncates them.

watch -n 5 -d cat /proc/mdstat
gunzip -c /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log.0 | grep "Invalid user" | awk '{print $8;}' | sort | uniq -c | less
awk -F "=| "
2009-03-02 21:09:51
User: Bender
Functions: awk cat file
9

You can use multiple field separators by separating them with | (=or).

This may be helpful when you want to split a string by two separators for example.

#echo "one=two three" | awk -F "=| " {'print $1, $3'}

one three

cat /dev/zero > /dev/null &
2009-03-02 18:18:52
User: gustavold
Functions: cat
-2

Just waste some resources in a philosophical way

cat file1.txt | uniq > file2.txt
$ cat /etc/*-release
cat /etc/*-release
2009-02-26 08:22:01
User: sudopeople
Functions: cat
9

Works for most distributions, tested on Ubuntu, Fedora, CentOS, Gentoo, SUSE, RedHat.

Debian and Slackware:

cat /etc/*version
cat /dev/tty > FILE
2009-02-25 01:43:47
User: Jo
Functions: cat
1

Takes input from the connected terminal and dumps it to the specified file. Stop writing and close file with control + D or the end of line character. Useful for copying+pasting large blobs of text over SSH to a new machine.

N="filepath" ; P=/proc/$(lsof +L1 | grep "$N" | awk '{print $2}')/fd ; ls -l $P | sed -rn "/$N/s/.*([0-9]+) ->.*/\1/p" | xargs -I_ cat $P/_ > "$N"
2009-02-21 02:31:24
User: laburu
Functions: awk cat grep ls sed xargs
5

Note that the file at the given path will have the contents of the (still) deleted file, but it is a new file with a new node number; in other words, this restores the data, but it does not actually "undelete" the old file.

I posted a function declaration encapsulating this functionality to http://www.reddit.com/r/programming/comments/7yx6f/how_to_undelete_any_open_deleted_file_in_linux/c07sqwe (please excuse the crap formatting).

mkfifo /tmp/fifo; cat /tmp/fifo | nc -l -p 1234 | tee -a to.log | nc machine port | tee -a from.log > /tmp/fifo
2009-02-20 04:00:15
User: prutser
Functions: cat mkfifo tee
26

Forwards localhost:1234 to machine:port, running all data through your chain of piped commands. The above command logs inbound and outbound traffic to two files.

Tip: replace tee with sed to manipulate the data in real time (use "sed -e 's/400 Bad Request/200 OK/'" to tweak a web server's responses ;-) Limitless possibilities.

check_disk -w 15% -c 10% $(for x in $(cat /proc/mounts |awk '{print $2}')\; do echo -n " -p $x "\; done)
cat foo.csv bar.csv | sort -t "," -k 2 | uniq
2009-02-19 20:23:03
User: rafeco
Functions: cat sort
2

The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

cat somefilehere.txt | ssh-xfer nametocallfile.txt -
2009-02-19 18:35:33
User: scubacuda
Functions: cat
0

from http://matt.ucc.asn.au/ssh-xfer/

"ssh-xfer is a hackish but handy way of transferring files from remote hosts to your local computer. Firstly, you need to run a slightly modified SSH authentication agent program on your local computer. Patches are available for both OpenSSH and PuTTY, see below. If you haven't used a SSH agent program before, this article seems to be reasonable, or you can look at the OpenSSH/PuTTY docs.

You don't need any modifications to your ssh client or server programs - only the modified SSH authentication agent, and the extra ssh-xfer program."

for i in $(cat listofservers.txt); do konsole --new-tab -e ssh $i; done
2009-02-19 16:32:36
User: nottings
Functions: cat ssh
4

creates a new tab for each of N servers in listofservers.txt and ssh's to said servers

then, try the "send to all sessions" feature of konsole to do the same work on all servers at the same time. BIG time saver, but be careful!

cat .ssh/id_dsa.pub | ssh elsewhere "[ -d .ssh ] || mkdir .ssh ; cat >> .ssh/authorized_keys"
2009-02-18 22:13:04
User: jsiren
Functions: cat ssh
5

Enter your ssh public key in the remote end for future key-based authentication. Just type your password one last time. The next time you should be able to login with the public key. If you don't have a key, generate one with ssh-keygen.

Requires Bourne-compatible shell in the remote end.

cat /dev/urandom > /dev/dsp
2009-02-18 21:40:29
User: joem86
Functions: cat
4

This command will generate white noise through your speakers (assuming you have sound enabled). It's good for staying focused, privacy, coping with tinnitus, etc. I use it to test that the sound works.

cat /dev/mem > /dev/audio
ssh user@host cat /path/to/some/file | xclip
2009-02-18 10:56:38
User: raphink
Functions: cat ssh
Tags: X X11
18

Have you ever had to scp a file to your work machine in order to copy its contents to a mail? xclip can help you with that. It copies its stdin to the X11 buffer, so all you have to do is middle-click to paste the content of that looong file :)

On PC1: nc -l -p 6666 > /dev/dsp On PC2: cat /dev/dsp | nc <PC1's IP> 6666
2009-02-18 00:39:32
User: someguy
Functions: cat
6

Sends the microphone input from PC1 to the speakers of PC2. Do the same in reverse to have an actual conversation ;) ... maybe with another port tough

cat /proc/cpuinfo
2009-02-17 14:50:29
User: stinger
Functions: cat
-4

how to get full cpu info of your (linux) box

cat /dev/urandom | gzip -9 > /dev/null &
2009-02-16 14:12:38
Functions: cat gzip
3

check your load with top... Start more of these jobs to get an multi-core cpu busy...

cat ~/.ssh/*.pub | ssh user@remote-system 'umask 077; cat >>.ssh/authorized_keys'
MAC=`(date; cat /proc/interrupts) | md5sum | sed -r 's/^(.{10}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`
2009-02-16 07:09:43
User: vaporub
Functions: cat md5sum sed
15

Original author unknown (I believe off of a wifi hacking forum).

Used in conjuction with ifconfig and cron.. can be handy (especially spoofing AP's)

sudo aptitude -y install iasl && sudo cat /sys/firmware/acpi/tables/DSDT > dsdt.dat && iasl -d dsdt.dat
2009-02-15 23:13:50
User: brettalton
Functions: cat install sudo
-1

In July 2008, there was an uproar over Foxconn motherboards feeding Linux installs incorrect ACPI information (http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=869249).

Foxconn has gladly corrected their mistake, but make sure it's not happening on your motherboard!

After running the command, just view the 'dsdt.dsl' in any editor you like.