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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 wc from sorted by
Terminal - Commands using wc - 157 results
read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
2013-03-10 08:59:45
User: rodolfoap
Functions: cat chmod echo gpg read sed wc

(Please see sample output for usage)

Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.:

myscript --> myscript.crypt

You can execute myscript.crypt only if you know the password. If you die, your script dies with you.

If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string).

Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner.

Sorry for the chmod on parentheses, I dont like "-" at the end.

Thanks flatcap for the subshell abbreviation to /dev/null

ps -u user_name_here | grep process_name_here | wc -l
find . -type f -name "*.txt" | while read; do (($(cat $THISFILE | wc -l) < 10)) && rm -vf "$THISFILE"; done
for x in `ps -u 500 u | grep java | awk '{ print $2 }'`;do ls /proc/$x/fd|wc -l;done
echo 'foo' | tee >(wc -c) >(grep o) >(grep f)
2013-01-31 09:54:18
User: totti
Functions: echo grep tee wc
Tags: tee output input

Output of a command as input to many

for i in {a..z}; do echo $(cat ~/.bash_history | grep ^$i.* | wc -l) $i; done | sort -n -r
2013-01-23 18:59:13
User: yaMatt
Functions: cat echo grep sort wc

Kind of fun if you're that was inclined. I figured most of my commands start with s. sudo, screen, ssh etc. This script tells me what else they start with.

ls | wc -l
2013-01-22 03:35:35
User: Sebasg
Functions: ls wc

ls -1 shows one file per line (update: -1 was not really needed)

wc -l counts the lines received from the previous command

find . -type d | while read dir ; do num=`ls -l $dir | grep '^-' | wc -l` ; echo "$num $dir" ; done | sort -rnk1 | head
for host in $HOSTNAMES; do ping -q -c3 $host && ssh $host 'command' & for count in {1..15}; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done &>/dev/null
for host in $MYHOSTS; do ping -q -c3 $H 2>&1 1>/dev/null && ssh -o 'AllowedAuthe ntications publickey' $host 'command1; command2' & for count in 1 2 3 4 5; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done
2012-11-13 23:12:27
User: a8ksh4
Functions: grep host jobs kill ping sleep ssh wc

Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system.

Maybe there's an easier way to set a timeout in the ssh options...

find -maxdepth 3 -type d | while read -r dir; do printf "%s:\t" "$dir"; find "$dir" | wc -l; done
2012-10-15 15:00:09
User: brainstorm
Functions: find printf read wc

Counts the files present in the different directories recursively. One only has to change maxdepth to have further insight in the directory hierarchy.

Found at unix.stackexchange.com:


ls|wc -l
NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
2012-10-02 03:57:51
User: toxick
Functions: awk echo sleep wc

Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time.

find . \( -iname '*.cpp' -o -iname '*.h' \) -exec wc -l {} \; | sort -n | cut --delimiter=. -f 1 | awk '{s+=$1} END {print s}'
2012-09-19 15:21:01
User: jecxjoopenid
Functions: awk cut find sort wc

Searches for *.cpp and *.h in directory structure, counts the number of lines for each matching file and adds the counts together.

netstat -an | grep 80 | wc -l
centralized(){ L=`echo -n $*|wc -c`; echo -e "\x1b[$[ ($COLUMNS / 2) - ($L / 2) ]C$*"; }
2012-08-16 18:19:26
User: xenomuta
Functions: echo wc
Tags: echo ansi

Echoes text horizontally centralized based on screen width

git log --pretty=oneline b56b83.. | wc -l
git log --summary 223286b.. | grep 'Author:' | wc -l
ls -d1 pattern*/ | wc -l
find /some/path -type f -and -iregex '.*\.mp3$' -and -print0 | tr -d -c '\000' |wc -c
2012-03-31 21:57:33
User: kyle0r
Functions: find tr wc

In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex).

It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes.

The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count.

I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check.

The approach can be made in to a function and then included in .bashrc or similar. e.g.

count_chars() { tr -d -c "$1" | wc -c; }

In this form it provides a versatile character counter of text streams :)

find . -type f -name "*.*" -exec cat {} > totalLines 2> /dev/null \; && wc -l totalLines && rm totalLines
who am i | wc -l
cat z.log | cut -d ':' -f1 | sort | uniq | xargs -l1 -iFF echo 'echo FF $(cat z.log | grep -e "^FF" | grep -e Timeout | wc -l )' | bash
find . -maxdepth 1 -type f | wc -l
sayspeed() { for i in $(seq 1 `echo "$1"|wc -c`); do echo -n "`echo $1 |cut -c ${i}`"; sleep 0.1s; done; echo "";}
2012-02-11 05:51:42
User: kundan
Functions: echo seq sleep wc

change the time that you would like to have as print interval

and just use it to say whatever you want to