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Convert JSON to YAML

Requires installing yq (pip install yq)
This is sample output - yours may be different.
0

yq . -y <example.json

rvorlicek · 2018-12-13 08:16:59 0
Silently deletes lines containing a specific string in a bunch of files

This command will find all occurrences of one or more patterns in a collection of files and will delete every line matching the patterns in every file
This is sample output - yours may be different.
1

for file in $(egrep 'abc|def' *.sql | cut -d":" -f1 | uniq); do sed -i '/abc/d' ./$file ; sed -i '/def/d' ./$file; done

guillaume1306 · 2018-12-10 16:23:20 1
coloured shell prompt

This coloured prompt will show: username in green, grey "@" sign, hostname in red, current directory in yellow, typed commands in green.
This is sample output - yours may be different.
1

export PS1="\e[1;32m\u\e[0m@\e[1;31m\h\e[0m\e[1;33m\w:#> \e[1;32m"

guillaume1306 · 2018-12-10 14:08:06 0
Converts all pngs in a folder to webp using all available cores

As an alternative to the above command, this one ditches the unnecessary and complicated for loop in favor of a way faster multi-core approach for a task that's more CPU than I/O intensive, making it a perfect suite for GNU parallel
This is sample output - yours may be different.
1

parallel cwebp -q 80 {} -o {.}.webp ::: *.png

kostis · 2018-12-07 23:37:24 0
quick integer CPU benchmark

You could have that little benchmark run on all cores in parallel, as a multi-core benchmark or stress test First find the number of cores, then have parallel iterate over that in, well, parallel Show Sample Output
This is sample output - yours may be different.
```
...
41454625947560171969501001538543925124881846970621917597708878154881\
18278788738248093374936943243527734573872009289119068940335579136

real	0m12,698s
user	0m14,461s
sys	0m0,382s
```
0

time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "2^2^20" '|' bc

kostis · 2018-12-06 05:36:55 0
small CPU benchmark with PI, bc and time.

Broken in two parts, first get the number of cores with cat /proc/cpuinfo |grep proc|wc -l and create a integer sequence with that number (xargs seq), then have GNU parallel loop that many times over the given command. Cheers! Show Sample Output
This is sample output - yours may be different.
```
...
66983895228684783123552658213144957685726243344189303968642624341077\
3226978028073189154411010446823252716201052652272111660396

real	0m31,847s
user	0m59,085s
sys	0m0,151s
```
0

time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "scale=4000\; a$1$\*4" '|' bc -l

kostis · 2018-12-06 05:15:24 0
replace recursive in folder with sed
This is sample output - yours may be different.
1

find <folder> -type f -exec sed -i 's/my big String/newString/g' {} +

aysadk · 2018-12-05 00:50:23 3
Get the running Kernel and Install date

Get the running Kernel and Install date
This is sample output - yours may be different.
0

uname -a;rpm -qi "kernel"-`uname -r`|grep "Install"

Skyman · 2018-12-04 17:27:30 0
converts all pngs in a folder to webp, quality can be choosed as a argument

needs cwebp
This is sample output - yours may be different.
0

pngwebp(){ arg1=$1 for i in *.png; do name=`echo "${i%.*}"`; echo $name; cwebp -q $1 "${i}" -o "${name}.webp" done }

k2arim99 · 2018-12-01 14:38:05 0
zgrep across multiple files
This is sample output - yours may be different.
1

find "$(pwd)" -name "file-pattern*.gz" -exec zgrep -H 'pattern' {} \;

jgleeson · 2018-11-23 13:15:43 0
highlight with grep and still output file contents
This is sample output - yours may be different.
1

grep --color -E 'pattern|' file

jgleeson · 2018-11-23 13:13:47 0
draw honeycomb

Fill the entire terminal screen. Is COLUMNS or LINES are undefined run "resize"
This is sample output - yours may be different.
2

yes "\\__/ " | tr "\n" " " | fold -$((($COLUMNS-3)/6*6+3)) | head -$LINES

tomhol · 2018-11-23 08:21:55 1
Watch how many tcp connections there are per state every two seconds.

slighty shorter
This is sample output - yours may be different.
1

watch -c "netstat -nt | awk 'FNR > 3 {print \$6}' | sort | uniq -c"

sreimann · 2018-11-22 12:13:43 0
Watch how many tcp connections there are per state every two seconds.
This is sample output - yours may be different.
0

$ watch -c "netstat -natp 2>/dev/null | tail -n +3 | awk '{print \$6}' | sort | uniq -c"

emanuele · 2018-11-22 10:37:48 0
Rename all files in lower case

rename is a really powerfull to, as its name suggests, rename files Show Sample Output
This is sample output - yours may be different.
```
aETEBezhrhe.txt REHTY.txt rthureioght.txt
becomes :
aetebezhrhe.txt rehty.txt rthureioght.txt
```
2

rename 'y/A-Z/a-z/' *

keltroth · 2018-11-21 13:41:24 0
Rename all files in lower case
This is sample output - yours may be different.
0

for f in `find`; do mv -v "$f" "`echo $f | tr '[A-Z]' '[a-z]'`"; done

emanuele · 2018-11-21 11:52:31 0
Delete all files by extension

This is a correction to https://www.commandlinefu.com/commands/view/22134 Use `-name` instead of `-iname`, because case-sensitivity is probably important when we're dealing with filenames. It's true that extensions are often capitalised (e.g., "something.JPG"), so choose whatever's appropriate. However, what is appropriate is the quoting of the name pattern, so the shell doesn't expand it incorrectly. Finally, `-delete` is clearer.
This is sample output - yours may be different.
1

find / -name "*.jpg" -delete

Xophmeister · 2018-11-19 11:11:20 0
Generate a sequence of numbers.

# for description type man seq Show Sample Output
This is sample output - yours may be different.
```
1
2
3
4
5
6
7
8
9
10
11
12
```
0

seq 12

flxndn · 2018-11-14 13:17:52 0
draw honeycomb

tput setaf 1 && tput rev && seq -ws "___|" 81|fold -69|tr "0-9" "_" && tput sgr0 # (brick wall)
This is sample output - yours may be different.
6

seq -ws "\\__/" 99|fold -69|tr "0-9" " "

knoppix5 · 2018-11-13 06:39:37 0
draw mesh
This is sample output - yours may be different.
2

seq -s " \\_/" 256|tr -d "0-9"|fold -70

knoppix5 · 2018-11-12 23:25:25 0
Print a horizontal line

Replace the underscore with any other character. e.g. + or - or =
This is sample output - yours may be different.
2

printf "%`tput cols`s"|sed "s/ /_/g"

houghi001 · 2018-11-12 19:44:16 0
Produce 10 copies of the same string
This is sample output - yours may be different.
2

echo boo{,,,,,,,,,,}

wuziduzi · 2018-11-12 18:26:17 0
Sort by IP address
This is sample output - yours may be different.
1

sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4

wuziduzi · 2018-11-12 18:03:34 0
Show OS release incl version.

Show Sample Output
This is sample output - yours may be different.
```
Gentoo Base System release 2.6
```
1

grep -m1 -h [0-9] /etc/{*elease,issue} 2>/dev/null | head -1

wuziduzi · 2018-11-12 18:01:57 0
Print a horizontal line
This is sample output - yours may be different.
1

printf -v _hr "%*s" $(tput cols) && echo ${_hr// /${1--}}

wuziduzi · 2018-11-12 18:01:25 0
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See how many % of your memory firefox is using

Watch Al Jazeera Livestream directly in mplayer #jan25

One cannot call the high quality livestream directly, but command this gives you a session ID and the high quality stream. #egypt #jan25

show current directory

Opens a file or URL in the user's preferred application.

Execute a command at a given time

This is an alternative to cron which allows a one-off task to be scheduled for a certain time.

Show some trivia related to the current date

Contrary to logic, typing calendar won't show a calendar, that's the job of cal. Typing calendar will show some trivia related to the current date. Tested against many Linux distros and FreeBSD.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY

This version eliminates the grep before the awk, which is always good. It works for GNU core utils and ensures that the date output of ls matches the format in the pattern match, regardless of locale, etc. On BSD-based systems, you can easily eliminate both the grep and the awk: find . -maxdepth 1 -Btime -$(date +%kh%lm) -type f

Quick find function

A function that allows you to perform a case-insensitive search in the current directory, and directories in the current directory (but no further), for files containing the first argument anywhere in their names.

List all directories only.

Undocumented syntax, but should work on every shell. It'll list all directories in the current one. Change `*/` into globbing `**/` for recursivity.

list files recursively by size

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