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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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grep -E -rn --color=always --exclude-dir=".svn" --exclude-dir="packages" --exclude="*.swp" "(emit|on)\([\'\"]leader" ~/project/ | less -R
2014-12-23 20:08:25
User: hochmeister
Functions: grep less

grep for specific function invocations in this case, wither "emit" or "on" with "leader".

FILE=somefile.js; LOG=~/changes.diff; truncate -s0 ${LOG}; for change in $(svn log ${FILE} | awk -F' | ' '/^r[0-9]+/{print $1}'); do svn log -c ${change} >> ${LOG}; printf "\n" >> ${LOG}; svn diff -c ${change} >> ${LOG}; printf "\n\n\n" >> ${LOG}; done
2014-12-23 20:00:54
User: hochmeister
Functions: awk diff printf
Tags: svn diff log

from a svn repo, print a log, with diff, of each commit touching a given file

awk '{ total += gsub(/yourstring/,"") } END { print total }' yourfile
2014-12-16 21:00:45
User: bugmenot
Functions: awk

Count how many times a pattern is present into a file. It can be one or more lines. No overlapping. It means searching for aa on aaa will output 1 not 2.

echo something | awk '{ total += gsub(/yourstring/,"") } END { print total }'
2014-12-16 20:58:42
User: bugmenot
Functions: awk echo

Count how many times a pattern is present into a stream. It can be one or more lines. No overlapping. It means searching for aa on aaa will output 1 not 2.

cd -P .
curl -s "http://smacie.com/randomizer/borat.txt" | shuf -n 1 -
2014-12-16 04:18:48
User: benjabean1

Turns out smacie.com has a text file containing every single one of the borat quotes, each one on a newline. This makes it very convenient, as this can be done without any sed-parsing, and uses less bandwitdth!

Note that borate quotes are quite offensive, much more so than "fortunes-off"!

ls -l | head -n 65535 | awk '{if (NR > 1) total += $5} END {print total/(1024*1024*1024)}'
rsync -v --ignore-existing `ls | head -n 40` root@localhost:/location
scp -r `ls | grep -vE "(Pattern1|Pattern2)"` user@remote_host:/location
apt-cache pkgnames linux-
2014-12-14 06:48:57
User: benjabean1
Functions: apt

In this case, linux- is the prefix; simply running

apt-cache pkgnames

would list every package APT knows about.

The default APT config assumes -g, --generate; to use the cache as/is, you could similarly run:

apt-cache --no-generate pkgnames [prefix]

Adding --all-names, like so:

apt-cache --no-generate --all-names pkgnames [prefix]

would print all the packages APT knows about, using the cache as/is, including virtual packages and missing dependencies.

This command was shamelessly stolen from the apt-cache(8) man-page.

for USER in /var/spool/cron/*; do echo "--- crontab for $USER ---"; cat "$USER"; done
2014-12-11 19:48:46
User: tyzbit
Functions: cat echo

This is not exhaustive but after checking /etc/cron* is a good way to see if there are any other jobs any users may have set.

Note: this is a repost from a comment "flatcap" made on http://www.commandlinefu.com/commands/view/3726/print-crontab-entries-for-all-the-users-that-actually-have-a-crontab#comment, for which I am grateful and I take no credit.

strings /dev/urandom | tr -cd '[:alnum:]' | fold -w 30 | head -n 1
2014-12-11 06:21:51
User: atoponce
Functions: fold head strings tr

This command is similar to the alternate, except with head(1), you can pick as many passwords as you wish to generate by changing the number of lines you wish to preview.

ps axo pcpu,args | awk '/[p]hp.*pool/ { sums[$4] += $1 } END { for (pool in sums) { print sums[pool], pool } }' | sort -rn | column -t
find . -printf '%.5m %10M %#9u %-9g %TY-%Tm-%Td+%Tr [%Y] %s %p\n'|sort -nrk8|head
rpm -e --allmatches gpg-pubkey-1aa043b8-53b2e946
2014-12-09 21:27:08
User: krizzo
Functions: rpm
Tags: GPG rpm yum pubkey

This will remove the gpg-pubkey-1aa043b8-53b2e946 from rpm/yum and you'll be prompted to add it back from the given repo.

rpm -qa gpg-pubkey --qf "%{version}-%{release} %{summary}\n"
2014-12-09 21:23:28
User: krizzo
Functions: rpm
Tags: GPG rpm yum pubkey

This will list all the gpg keys that were accepted and installed for yum.

du -hs * |egrep -i "^(\s?\d+\.?\d+G)"
2014-12-09 15:23:21
User: krizzo
Functions: du egrep
Tags: size sort du

This will list all the files that are a gigabyte or larger in the current working directory. Change the G in the regex to be a M and you'll find all files that are a megabyte up to but not including a gigabyte.

x="() { :; }; echo x" bash -c :
2014-12-08 22:21:18
User: malathion
Functions: bash
Tags: Security bash

If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/

while sleep 1; do if [ $(echo "$(cat /proc/loadavg | cut -d' ' -f1) > .8 " | bc) -gt 0 ]; then echo -e "\n\a"$(date)" \e[5m"$(cat /proc/loadavg)"\e[0m"; ps aux --sort=-%cpu|head -n 5; fi; done
2014-12-08 15:44:40
User: tyzbit
Functions: cat echo head ps sleep

This checks the system load every second and if it's over a certain threshold (.8 in this example), it spits out the date, system loads and top 4 processes sorted by CPU.

Additionally, the \a in the first echo creates an audible bell.

(echo n; echo p; echo 3; echo 1; echo; echo; echo w; echo q) | /sbin/fdisk /dev/sda
sudo netstat -tulpn | grep :8080
mv -iv $FILENAME{,.$(stat -c %Z $FILENAME)}
2014-12-02 13:47:52
User: bunam
Functions: mv stat
Tags: mv


mv -iv $FILENAME{,.$(stat -c %Y $FILENAME)}

does it help ?

mv -iv $FILENAME{,.$(stat -c %y $FILENAME | awk '{print $1}')}
2014-12-01 22:41:38
User: pdxdoughnut
Functions: awk mv stat
Tags: mv

Note that the -i will not help in a script. Proper error checking is required.

find /srv/code -maxdepth 4 -type f -regex ".*\(\(package\|composer|npm\\|bower\)\.json\|Gemfile\|requirements\.txt\\|\.gitmodules\)"
2014-11-28 16:34:35
User: renoirb
Functions: find
Tags: bash git PHP ruby

List all dependencies manifests so you can install them.

In a scenario where you want to deploy a number of web applications and run their dependency managers, how could you run all of them in a systematic order.

One of the complexity is to ensure you get only your own top level dependencies. That way, you don recursively call development dependencies of your own dependencies.

Otherwise you might end up discovering dependency management manifests that are already been pulled by your own projects.

# Using this command

This command helps me find them and I can then run what?s required to pull them from their respective sources.

This command assumes the following:

1. Your code checkouts are in a flat repository layout (i.e. not nested).

2. Finds manifests for:

- NPM (nodejs),

- Composer (php),

- bower,

- requirements.txt (Python), and

- git submodules

find . -type f -name "*\?*" | while read f;do mv "$f" "${f//[^0-9A-Za-z.\/\(\)\ ]/_}";done
2014-11-28 14:55:27
User: miccaman
Functions: find mv read
Tags: bash find mv

replace all "?" characters in filename to underscore