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May 19, 2015 - A Look At The New Commandlinefu
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Commands tagged cat from sorted by
Terminal - Commands tagged cat - 48 results
awk '/text to grep/{print $1}' "log" | sort -n | uniq -c | sort -rn | head -n 100
2014-07-09 08:48:06
User: kln0thing
Functions: awk head sort uniq

Original command: cat "log" | grep "text to grep" | awk '{print $1}' | sort -n | uniq -c | sort -rn | head -n 100

This is a waste of multiple cats and greps, esp when awk is being used

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) }'
ls -1 | xargs ruby -e'puts ARGV.shuffle'
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.

find /usr/include/ -name '*.[c|h]pp' -o -name '*.[ch]' -print0 | xargs -0 cat | grep -v "^ *$" | grep -v "^ *//" | grep -v "^ */\*.*\*/" | wc -l
2013-06-17 08:37:37
Functions: cat find grep wc xargs

Count your source and header file's line numbers. This ignores blank lines, C++ style comments, single line C style comments.

This will not ignore blank lines with tabs or multiline C style comments.

cat filein | ssh destination.com -c arcfour,blowfish-cbc -C -p 50005 "cat - > /tmp/fileout"
2013-05-30 07:18:46
User: bhbmaster
Functions: cat ssh
Tags: cat ssh

Where filein is the source file, destination.com is the ssh server im copying the file to, -c arcfour,blowfish-cbc is selecting the fastest encryption engines, -C is for online compressions and decompression when it comes off the line - supposed to speed up tx in some cases, then the /tmp/fileout is how the file is saved...

I talk more about it on my site, where there is more room to talk about this:




tac filename.txt
cat $HISTFILE | grep command
history | tail -100 | grep cmd
2013-04-22 03:49:43
User: datamining
Functions: grep tail

this also can find the old command you used before

cat .bash_history | tail -100 | grep {command}
2013-04-10 10:40:52
User: techie
Functions: cat grep tail

I know how hard it is to find an old command running through all the files because you couldn't remember for your life what it was. Heres the solution!! Grep the history for it. depending on how old the command you can head or tail or if you wanted to search all because you cannot think how long ago it was then miss out the middle part of the command. This is a very easy and effective way to find that command you are looking for.

watch -n 1 "awk 'NR==3 {print \"Signal strength = \" \$3 \"00 %\"}''' /proc/net/wireless"
watch -n 1 cat /proc/net/wireless
2012-06-07 10:38:21
User: cantormath
Functions: cat watch

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.

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
Functions: cat read sleep sudo
Tags: cat streamer

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.


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

sed G input.txt | cat -s
find /usr/include/ -name '*.[c|h]pp' -o -name '*.[ch]' -exec cat {} \;|wc -l
2011-12-01 19:58:52
User: kerim
Functions: cat find wc

Count your source and header file's line numbers

For example for java change the command like this

find . -name '*.java' -exec cat {} \;|wc -l

for line in `cat $file`; do firefox -new-tab "$line" & 2>/dev/null; sleep 1; done
2011-11-12 13:47:24
User: hamsolo474
Functions: sleep

this will open a new tab in firefox for every line in a file

the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

cat x
cat -n file.txt
grep . *
2011-09-01 09:16:04
User: theist
Functions: grep
Tags: cat grep

If you have a bunch of small files that you want to cat to read, you can cat each alone (boring); do a cat *, and you won't see what line is for what file, or do a grep . *. "." will match any string and grep in multifile mode will place a $filename: before each matched line. It works recursively too!!

echo $(cat /usr/share/dict/words |grep -v "'"|shuf -n4)
2011-08-31 12:48:14
User: d1v3rdown
Functions: cat echo grep
Tags: cat echo grep shuf

Fast and excludes words with apostrophes. For ubuntu, you can use wamerican or wbritish dictionaries, installable through aptitude.

sort -R
2011-07-15 15:35:27
User: RyanM
Functions: sort

Randomizes a file. The opposite of sort is sort -R!

cat /dev/sda | pv -r > /dev/null
2011-01-23 22:58:56
User: kerim
Functions: cat

Change your drive letter as you wish.

Using pv command for speed detect.First of all you must install pv command for usage.



for _a in {A..Z} {a..z};do _z=\${!${_a}*};for _i in `eval echo "${_z}"`;do echo -e "$_i: ${!_i}";done;done|cat -Tsv

This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop.

I created a function for this and use it instead of env. (by aliasing env).

This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM.

aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; }

And my printenv replacement is:

alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"'

From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount