Commands by mikhail

Commands by mikhail (15)

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Shows a specific process memory usage
This is sample output - yours may be different.
1

mem() { ps -C "$1" -O rss | awk '{ count ++; sum += $2 }; END {count --; print "Number of processes:\t",count; print "Mem. usage per process:\t",sum/1024/count, "MB"; print "Total memory usage:\t", sum/1024, "MB" ;};'; }

mikhail · 2022-01-23 16:14:24 0
Display disk partition sizes

Use lsbk (list block) and jq (to manipulate a JSON on the command line) to display partition information: Show Sample Output
This is sample output - yours may be different.
```
["loop0","55.5M"]
["loop1","156M"]
["loop2","32.3M"]
["zram0","4G"]
["nvme0n1","476.9G"]
```
2

lsblk --json | jq -c '.blockdevices[]|[.name,.size]'

mikhail · 2021-12-22 22:31:07 0
Monitor memory without top or htop

It repeats a command, such as free, every five seconds and highlights the differences
This is sample output - yours may be different.
1

watch -n 5 -d '/bin/free -m'

mikhail · 2021-12-22 22:28:59 0
Find failures with journalctl

Sometimes things break. You can find the most recent errors using a combination of journalctl, along with the classic tools sort and uniq Show Sample Output
This is sample output - yours may be different.
```
898172 "/usr/bin/dockerd"
    752 "/usr/local/sbin/node_exporter"
     30 "/usr/bin/gnome-shell"
     26 "/usr/bin/cat"
     22 "/usr/libexec/gsd-media-keys"
[...]
```
1

journalctl --no-pager --since today --grep 'fail|error|fatal' --output json | jq '._EXE' | sort | uniq -c | sort --numeric --reverse --key 1

mikhail · 2021-12-22 22:27:17 0
Share a file quickly using a python web server

Raise your hand if you haven't used this at least once to share a directory quickly
This is sample output - yours may be different.
3

cd $mydir && python3 -m http.server 8888

mikhail · 2021-12-22 22:24:37 0
Apply a command on files with different names

The shell {} operator is great for this. Here's an example with three directories enclosed in {}:
This is sample output - yours may be different.
0

mkdir -p -v /home/user/tmp/{dir1,anotherdir,similardir}

mikhail · 2021-12-22 22:22:51 0
extract email addresses from some file (or any other pattern)
This is sample output - yours may be different.
1

grep -Eio '([[:alnum:]_.-]{1,64}@[[:alnum:]_.-]{1,252}?\.[[:alpha:].]{2,6})'

mikhail · 2020-07-22 22:40:33 2
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() { tr '[:upper:]' '[:lower:]' <<< "$(sed -z -r -e 's~[^[:alnum:]]+~ ~g' -e 's~ (he|here|how|it|she|there|what|when|where|who) s ~ \1 is ~gi' -e 's~^ *~~;s~ *$~~' -e 's~ +~-~g' - <<< " $(iconv -c -t ASCII//TRANSLIT//IGNORE - <<< " $@ " ) ")"; }


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

# output:
test-uaaaaaaaeceeeeiiiidnoooooouuuuyss-and-aaaaaaaeceeeeiiiidnoooooouuuuyy
```
1

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

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

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

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

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

mikhail · 2019-06-06 17:53:28 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
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
Remove scripts tags from *.html and *.htm files under the current directory
This is sample output - yours may be different.
0

find ./ -type f $ -iname '*.html' -or -iname '*.htm' $ -exec sed -i '/<script/,/<\/script>/d' '{}' \;

mikhail · 2019-05-10 23:27:12 0
stringContains: Determining if a String Contains a Substring

Show Sample Output
This is sample output - yours may be different.
```
function stringContains() { [ -z "${2##*$1*}" ] && [ -z "$1" -o -n "$2" ]; };

# Used like so
SRC_STRING="this is a sample string where TEST we want to check for the word 'TEST'"
if stringContains "TEST" "$SRC_STRING"; then
	echo "Found TEST in SRC_STRING"
else
	echo "Couldn't find TEST in SRC_STRING"
fi
```
2

function stringContains() { [ -z "${2##*$1*}" ] && [ -z "$1" -o -n "$2" ]; };

mikhail · 2019-04-12 20:51:27 0
Calculate the distance between two geographic coordinates points (latitude longitude)

The Haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes. Show Sample Output
This is sample output - yours may be different.
```
# input (format: latitude1 longitude1 latitude2 longitude2) :

h -22.9077611 -43.1259322 -22.9121089 -43.2301558

# output:
10.6889

# So, the distance between -22.9077611 (latitude),-43.1259322 (longitude) and -22.9121089,-43.2301558 (latitude,longitude) is 10,688.9 meters (10.6889 kilometers)
```
3

h(){ echo $@|awk '{d($1,$2,$3,$4);} function d(x,y,x2,y2,a,c,dx,dy){dx=r(x2-x);dy=r(y2-y);x=r(x);x2=r(x2);a=(sin(dx/2))^2+cos(x)*cos(x2)*(sin(dy/2))^2;c=2*atan2(sqrt(a),sqrt(1-a)); printf("%.4f",6372.8*c);} function r(g){return g*(3.1415926/180.);}';}

mikhail · 2019-04-04 01:34:36 0
worse alternative to <ctrl+r>

worse alternative to ctrl+r: grep the history removing duplicates without sorting (case insensitive search). Show Sample Output
This is sample output - yours may be different.
```
head ~/.bash_history # history sample for reference:
echo "duplicate"
awk --help
echo "duplicate"
echo "ctrl+r is better"

# input:
memo echo

# output:
echo "duplicate"
echo "ctrl+r is better"
```
1

function memo() { awk '! seen[$0]++' <<< $(grep -i "$@" ~/.bash_history ); }

mikhail · 2019-04-04 00:54:43 0

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Get all mac address

Get mac address listed for all interfaces.

add a gpg key to aptitute package manager in a ubuntu system

when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

vim multiple files at one time, split vertically.

Tired of switching between proxy and no proxy? here's the solution.

Replace 10.0.0.0/8 with your largest local subnet. replace 10.1.1.123:3128 with your proxy information.. Note this only works with a proxy server configured for passive setup.. Now your firefox transparently proxy's stuff destined outside your network.. and Doesn't proxy stuff inside your network. as well as all your other favorite web applications. curl, wget, aria2 ect.

Show crontabs for all users

This is flatcaps tweaked command to make it work on SLES 11.2

List the Sizes of Folders and Directories

I wanted an easy way to list out the sizes of directories and all of the contents of those directories recursively.

Print the contents of $VARIABLE, six words at a time

Print out the contents of $VARIABLE, six words per line, ignoring any single or double quotes in the text. Useful when $VARIABLE contains a sentence that changes periodically, and may or may not contain quoted text.

Check a server is up. If it isn't mail me.

For some reason the 2&>1 does not work for me, but the shorter stdout/stderr redirection >& works perfectly (Ubuntu 10.04).

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"

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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