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Alert visually until any key is pressed
This is sample output - yours may be different.
1

while true; do echo -e "\e[?5h\e[38;5;1m A L E R T $(date)"; sleep 0.1; printf \\e[?5l; read -s -n1 -t1 && printf \\e[?5l && break; done

knoppix5 · 2019-06-18 15:27:36 0
Generrate Cryptographically Secure RANDOM PASSWORD

Change :alnum: to :graph: for all printable characters Show Sample Output
This is sample output - yours may be different.
```
FH170AB1DXb4dHlX
```
-1

cat /dev/urandom |tr -c -d '[:alnum:]'|head -c 16;echo

AndrewM · 2019-06-17 17:51:04 0
automatically generate the ip/hostname entry for the /etc/hosts in the current system

I use it after a clean CentOS 7 minimal server installation to automatically populate the /etc/hosts file. Not sure why the installation does not add this entry by itself. Tested on CentOS 7 with the simplest use case: 1 static ip address and the hostname provided during installation. Show Sample Output
This is sample output - yours may be different.
```
[root@dns-server ~]# echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)"
10.0.2.10 dns-server.mydomain.lab dns-server

[root@dns-server ~]# echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)" >> /etc/hosts

[root@dns-server ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
10.0.2.10 dns-server.mydomain.lab dns-server
```
0

echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)"

acavagni · 2019-06-15 16:40:38 0
Generrate Cryptographically Secure RANDOM PASSWORD

Explination: https://stackoverflow.com/questions/2257441/random-string-generation-with-upper-case-letters-and-digits/23728630#23728630 Why 16 Characters: https://www.wired.com/story/7-steps-to-password-perfection/ Show Sample Output
This is sample output - yours may be different.
```
a7Bt4WGSz8hjJWIP
```
0

python -c "import string; import random;print(''.join(random.SystemRandom().choice(string.ascii_uppercase + string.digits + string.ascii_lowercase) for _ in range(16)))"

rootduck · 2019-06-14 17:35:12 2
tmux start new session with title and execute command

in this examp start htop command in tmux session over the shell cosole and set title for the tmux without doing it manuelly in tmux
This is sample output - yours may be different.
1

tmux new-session -d -s "SessionName" "htop"

aysadk · 2019-06-14 12:44:33 0
Clear terminal Screen

Probably the quickest / easiest way to clear the screen.
This is sample output - yours may be different.
2

<ctrl+l>

vicgedris · 2019-06-12 18:24:56 1
Clear terminal Screen
This is sample output - yours may be different.
-1

clear

vicgedris · 2019-06-12 18:21:51 0
Clear terminal Screen
This is sample output - yours may be different.
-1

tput clear

mpb · 2019-06-12 17:51:31 0
get a list of top 1000 sites from alexa

a little bit smarter & i only want .de domains, so ..... Show Sample Output
This is sample output - yours may be different.
```
amazon.de
google.de
ebay.de
ebay-kleinanzeigen.de
spiegel.de
web.de
bild.de
t-online.de
poe.trade
mobile.de
chip.de
```
0

curl -qsSl http://s3.amazonaws.com/alexa-static/top-1m.csv.zip 2>/dev/null | zcat | grep ".de$" | head -1000 | awk -F, '{print $2}'

dbiesecke · 2019-06-12 02:48:42 0
Define a word from Linux Terminal

The link gets the definition from vocabulary.com. In case you are behind firewall, use --proxy URL in the curl option. Show Sample Output
This is sample output - yours may be different.
```
A welcome is a greeting that usually comes when you first arrive. Although you aren;t fond of Aunt Martha, you always manage to give her a warm welcome when she comes to visit.
```
0

function define() { curl -s https://www.vocabulary.com/dictionary/$1 | grep 'og:description' | sed 's/&#[0-9][0-9][0-9]//g' | awk -F "\"" '{print $4}' }; define welcome

snehanshu11 · 2019-06-11 11:57:15 0
Find Apache Root document

Where is my Apache public_html ?!
This is sample output - yours may be different.
0

grep -i 'DocumentRoot' /usr/local/apache/conf/httpd.conf

locvfx · 2019-06-09 15:48:13 0
Convert epoch date to human readable date format in a log file.
This is sample output - yours may be different.
0

cat /var/log/mosquitto/mosquitto.log | awk -F : '{"date -d @"$1 |& getline D; print D, $0}'

ifebi · 2019-06-09 07:35:25 0
Slugify: converts strings in any language into Slugs (friendly names to use in URLs and filenames)

Slug the part of an URL which identifies a page using human-readable keywords. Slugs are used to construct friendly URLs (often for permalinks) that are easy to type, descriptive, and easy to remember. Show Sample Output
This is sample output - yours may be different.
```
function slugify() { echo "$@" | iconv -c -t ASCII//TRANSLIT//IGNORE | sed -r -e 's~[^[:alnum:]]+~ ~g' -e 's~^ *~~;s~ *$~~' -e 's~ +~-~g' | tr A-Z a-z; }


# testing special characters and spaces:
slugify " Test: µÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝß      and àáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿ ";

# output:
test-uaaaaaaaeceeeeiiiidnoooooouuuuyss-and-aaaaaaaeceeeeiiiidnoooooouuuuyy
```
0

function slugify() { echo "$@" | iconv -c -t ASCII//TRANSLIT//IGNORE | sed -r -e 's~[^[:alnum:]]+~ ~g' -e 's~^ *~~;s~ *$~~' -e 's~ +~-~g' | tr A-Z a-z; }

mikhail · 2019-06-08 17:45:57 0
WSL: Change the current directory converting a Windows path to a Linux Path

The Windows Subsystem for Linux (WSL) is a compatibility layer for running binary Linux executables natively in Windows. A folder such as "C:\Program Files (x86)\Common Files" is represented as "/mnt/c/Program Files (x86)/Common Files". This function allows you to change the current directory to a Windows folder. Show Sample Output
This is sample output - yours may be different.
```
function _cd() { local dir="$(echo -n "${*//'\'/"/"}" |  sed -e 's~$[a-z]$:~/mnt/\L\1~gi')";  if [ -d "$dir" ]; then cd "$dir"; fi; }

# double quotes are necessary:
_cd "C:\Program Files (x86)\Common Files";

# result: cd "/mnt/c/Program Files (x86)/Common Files"
```
0

function _cd() { local dir="$(echo -n "${*//'\'/"/"}" | sed -e 's~$[a-z]$:~/mnt/\L\1~gi')"; if [ -d "$dir" ]; then cd "$dir"; fi; }

mikhail · 2019-06-06 17:53:28 0
get a rough estimate about how much disk space is used by all the currently installed debian packages

The vaule is expressed in megabytes Show Sample Output
This is sample output - yours may be different.
```
$ echo $[ ($(dpkg-query -s $(dpkg --get-selections | grep -oP '^.*(?=\binstall)') | grep -oP '(?<=Installed-Size: )\d+' | tr '\n' '+' | sed 's/+$//')) / 1024 ]
4506
```
0

echo $[ ($(dpkg-query -s $(dpkg --get-selections | grep -oP '^.*(?=\binstall)') | grep -oP '(?<=Installed-Size: )\d+' | tr '\n' '+' | sed 's/+$//')) / 1024 ]

acavagni · 2019-06-02 16:35:34 0

get the full description of a randomly selected package from the list of installed packages on a debian system

I put this command on my ~/.bashrc in order to learn something new about installed packages on my Debian/Ubuntu system each time I open a new terminal Show Sample Output

dpkg-query --status $(dpkg --get-selections | awk '{print NR,$1}' | grep -oP "^$( echo $[ ( ${RANDOM} % $(dpkg --get-selections| wc -l) + 1 ) ] ) \K.*")

acavagni · 2019-06-01 13:24:07 0

Filter the output of a file continously using tail and grep

The OPs solution will work, however on some systems (bsd), grep will not filter the data, unless the --line-buffered option is enabled.
This is sample output - yours may be different.
1

tail -f $FILENAME | grep --line-buffered $PATTERN

FluffyBrick · 2019-05-30 21:01:59 0
Filter the output of a file continously using tail and grep
This is sample output - yours may be different.
1

tail -f path | grep your-search-filter

gmadorell · 2019-05-30 14:08:39 0
PHP7 - Fix incompatibility errors like: Parse error: syntax error, unexpected new (T_NEW) in file.php on line...

New objects cannot be assigned by reference. The result of the new statement can no longer be assigned to a variable by reference. Check the "Sample Output" example ("sample.php"). The Output of the above example in PHP 5: "Deprecated: Assigning the return value of new by reference is deprecated in sample.php on line 3". Output of the above example in PHP 7: "Parse error: syntax error, unexpected 'new' (T_NEW) in sample.php on line 3. Show Sample Output
This is sample output - yours may be different.
```
echo -e "<?php\nclass C {}\n\$c =& new C;\n?>" > sample.php
cat sample.php
<?php
class C {}
$c =& new C;
?>
busybox sh -c 'find "$(realpath ./)" -type f $ -iname "*.php" -or -iname "*.inc" $ -exec sed -i -r "s~=[[:space:]]*&[[:space:]]*new[[:space:]]+~= new ~gi" {} \; '
cat sample.php
<?php
class C {}
$c  = new C;
?>
```
0

find "$(realpath ./)" -type f $ -iname "*.php" -or -iname "*.inc" $ -exec sed -i -r "s~=[[:space:]]*&[[:space:]]*new[[:space:]]+~= new ~gi" {} \;

mikhail · 2019-05-29 18:20:45 0

find directory with most inodes/files

Find which directory in one filesystem that contains most inodes or files. Show Sample Output

find / -xdev -printf '%h\n' | sort | uniq -c | sort -k 1 -n | tail

Raboo · 2019-05-24 12:01:30 0

Scan all open ports without any required program
This is sample output - yours may be different.
5

for i in {1..65535}; do (echo < /dev/tcp/127.0.0.1/$i) &>/dev/null && printf "\n[+] Open Port at\n: \t%d\n" "$i" || printf "."; done

emphazer · 2019-05-21 09:34:15 5
Identifies the file types in a directory and adds or replaces their file extensions.

It tries to identify the file types in a directory and adds or replaces them with their appropriate extensions. Please, update the "file" tool before use it (last version: 5.37): https://github.com/file/file
This is sample output - yours may be different.
0

find "$(realpath .)" -type f -exec bash -c 'p="{}"; b="${p##*/}"; e=${b#"${b%.*}"}; e2=$(file -b -F="" --extension "$p"| awk -F/ '\''$1~/^\w+$/ {print $1} '\''); if [ "$e" != ".$e2" ] && [ ! -z $e2 ]; then mv "$p" "${p%$b}${b%$e}.$e2"; fi;' \;

mikhail · 2019-05-18 01:56:25 0
Random number with a normal distribution between 1 and X

Print a random number between 1 and 50 with a normal distribution around the center. The numbers around the middle are the most likely to occur and the farther you get from that the less and less common they are. You can test this and observe the number distribution with this command: for i in `seq 100000`; do echo $[(${RANDOM}%40+${RANDOM}%40)/2+1]; done | sort -n | uniq -c Show Sample Output
This is sample output - yours may be different.
```
30
```
0

echo $[(${RANDOM}%100+${RANDOM}%100)/2+1]

varenc · 2019-05-16 00:58:25 0
Replace strings in text

-e is the script function, it performs search and replace like vi, and -i is the edit the file in place.
This is sample output - yours may be different.
1

sed -e 's/dapper/edgy/g' -i /etc/apt/sources.list

yusufk · 2019-05-14 21:57:29 0
Clear Screen
This is sample output - yours may be different.
0

printf "\033c"

wuziduzi · 2019-05-13 19:58:09 1
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Generic shell function for modifying files in-place

Some commands (such as sed and perl) have options to support in-place editing of files, but many commands do not. This shell function enables any command to change files in place. See the sample output for many examples. The function uses plain sh syntax and works with any POSIX shell or derivative, including zsh and bash.

Getting information about model no. of computer

This command gives a model information of a computer. Also useful in determining the host is a VM machine or actual physical machine.

Install pip with Proxy

Installs pip packages defining a proxy

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

du and sort to find the biggest directories in defined filesystem

This command give a human readable result without messing up the sorting.

Apply substitution only on the line following a marker

I've been auto-generating some complex GnuPlots; with multiplots the first plot of each group needs to be a 'plot' whereas the others need to be 'replots' to allow overplotting/autoscaling/etc to work properly. This is used to replace only the first instance of 'replot'.

download and unpack tarball without leaving it sitting on your hard drive

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

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