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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands using cat from sorted by
Terminal - Commands using cat - 445 results
echo "DISK:";df -Pl | grep -v "Filesystem" | awk '{print $5,$6}' ; echo "MEM:" ; free -mto | awk '{ print $1,$2,$3,$4 }'; echo "CPU:"; top -b -d1 -n1 | grep Cpu | awk '{print $2,$3,$4,$5,$6,$7,$8,$9}';echo "LOAD:"; cat /proc/loadavg
2014-09-29 12:43:52
User: injez
Functions: awk cat df echo free grep top

Monitoring system in one line :

DISK : disk space

MEM: memory ( mem , swap, Total)

CPU : all information about cpu activity

LOAD : load average

cat /var/log/syslog | grep score= | awk '{print $15}' | more
w !sudo cat >%
cat h.txt| while read line; do curl -s -X POST 'https://www.virustotal.com/vtapi/v2/file/report' --form apikey="APIKEY" --form resource="$line"|awk -F'positives\":' '{print "VTHits"$2}'|awk -F' ' '{print $1" "$2$5$6}'|sed 's/["}]//g' && sleep 15; done
cat "log" | grep "text to grep" | awk '{print $1}' | sort -n | uniq -c | sort -rn | head -n 100
$ wget --no-check-certificate -q checkip.dyndns.org -O index.html && cat index.html|cut -d ' ' -f 6 | cut -d '<' -f 1
2014-05-12 07:10:29
User: Superkikim
Functions: cat cut wget

This is the command line I use to get my IP address in order to update my zoneedit account. Full script on my blog http://akim.sissaoui.com/linux-attitude/script-de-mise-a-jour-ddns-zoneedit-com-en-bashsh/

cat ~/.ssh/id_rsa.pub | ssh deployer@xxxxx -p 52201 'cat >> ~/.ssh/authorized_keys'
for i in $(cat vulns.txt); do echo $i; rpm -qa ?changelog | grep -i $i; done
2014-04-30 16:11:14
User: sonny108
Functions: cat echo grep rpm

Found it online and could be very useful

cat dictionary.txt|while read a; do echo $a|cryptsetup luksOpen /dev/sda5 sda5 $a && echo KEY FOUND: $a; done
2014-04-16 18:49:53
User: rodolfoap
Functions: cat echo read

Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command using a dictionary.

for i in {1..256};do p=" $i";echo -e "${p: -3} \\0$(($i/64*100+$i%64/8*10+$i%8))";done|cat -t|column -c120
2014-04-04 16:54:53
User: AskApache
Functions: cat column echo

Prints out an ascii chart using builtin bash! Then formats using cat -t and column.

The best part is:

echo -e "${p: -3} \\0$(( $i/64*100 + $i%64/8*10 + $i%8 ))";

From: http://www.askapache.com/linux/ascii-codes-and-reference.html

num_errs=`grep ERROR /var/log/syslog | tee >(cat >&2) | wc -l`
2014-03-12 00:04:24
Functions: cat tee wc

Many circumstances call for creating variable of a summary result while still printing the original pipe. Inserting "tee >(cat >&2)" allows the command output to still be printed while permitting the same output to be processed into a variable.

cat skype_log | sed -s 's/\(\[.*\]\) \(.*\): \(.*\)/<\2> \3/'
pdftk *.pdf cat output merged.pdf
2014-03-02 01:53:37
User: o0110o
Functions: cat

Merge Multiple PDFs In Alphabetical Order

cat /proc/cpuinfo | grep BogoMIPS | uniq | sed 's/^.*://g' | awk '{print($1 / 4) }'
cat cachedump.txt | awk -F : '{print $2":"$1}'
find . -name *.properties -exec /bin/echo {} \; -exec cat {} \; | grep -E 'listen|properties'
while true; do cat "file"; done | nc -v -l 1337
2014-02-06 03:02:58
User: bknk
Functions: cat

A TCP server that keeps the same socket open, sending the contents of "file" repeatedly.

cat /dev/urandom | env LC_CTYPE=C tr -dc a-zA-Z0-9 | head -c 16; echo
2014-02-05 15:04:07
User: yakovlev
Functions: cat env head tr

Feel free to put this in your ~/.profile:

random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; }

Then use it to generate passwords:

random [:alnum:] 16

Or DNA sequences:

random ACGT 256
cat /etc/shadow
find . -name "*.URL" | while read file ; do cat "$file" | sed 's/InternetShortcut/Desktop Entry/' | sed '/^\(URL\|\[\)/!d' > "$file".desktop && echo "Type=Link" >> "$file".desktop ; done
diff <(cat /etc/fstab | grep vol | grep -v "^#" | awk '{print $1}') <(df -h | grep vol)
2014-01-23 15:18:08
User: Koobiac
Functions: awk cat df diff grep
Tags: diff fstab df

With this command, you can check the difference between the volumes mounted and the volume in /etc/fstab.

proot -r /media/user/ubuntu12.10/ cat /etc/motd
2014-01-21 07:50:22
User: totti
Functions: cat

PRoot is a user-space implementation of chroot, mount --bind, and binfmt_misc. This means that users don't need any privileges or setup to do things like using an arbitrary directory as the new root filesystem, making files accessible somewhere else in the filesystem hierarchy, or executing programs built for another CPU architecture transparently through QEMU user-mode. Also, developers can use PRoot as a generic Linux process instrumentation engine thanks to its extension mechanism, see CARE for an example. Technically PRoot relies on ptrace, an unprivileged system-call available in every Linux kernel.


echo "text to prepend" | cat - file
2013-12-18 15:54:17
User: leni536
Functions: cat echo
Tags: cat replace

Prepend text to a file. It doen't need temporary files, ed or sed.