Linux

  sudo apt install build-essential
  sudo apt install libcurl4-openssl-dev
  sudo apt install libsqlite3-dev
  sudo apt install pkg-config
  sudo apt install git
  sudo apt install curl
  curl -fsS https://dlang.org/install.sh | bash -s dmd

  # For notifications
  sudo apt install libnotify-dev

  Run `source ~/dlang/dmd-2.098.1/activate` in your shell to use dmd-2.098.1.
  This will setup PATH, LIBRARY_PATH, LD_LIBRARY_PATH, DMD, DC, and PS1.
  Run `deactivate` later on to restore your environment.

# Cheatsheet

# basic functions
$ task list
$ task add Some description
$ task 1 done
$ task 1 delete

# Add priority
$ task add priority:H Pay bills

# Show tasks ordered by priority
$ task next

# With a project
task add project:Home Some description 

# Connect to a DB file
$ sqlite3 mySQLLiteFile.db

# Once connected, you have the sqllite command prompt
sqlite>

# Exit from sqlite command prompt :)
Ctrl+d

# Command to list all tables
.tables

# Comamnd to select something from a table - NB for ; at the end
select * from MyTable where someColumnName = '%partialValueMatch%';

  # run the docker image 
  docker run --name slidev --rm -it --user node -v ${PWD}:/slidev -p 3030:3030 tangramor/slidev:latest

  # Export the slides to static SPA - NB need to update the relative links "/assets" becomes "./assets". Also need to run on a webserver
  docker exec -i slidev npx slidev export

# from mint machine
dog@kennel:~$ zsh
                                                                                
New config: ~/.p10k.zsh.
Backup of ~/.zshrc: /tmp/.zshrc.JZtb3qunUJ.

See ~/.zshrc changes:

  diff /tmp/.zshrc.JZtb3qunUJ ~/.zshrc

    à - AltGr ` a
    è - AltGr ` e
    é - AltGr ' e

    € - AltGr = e
    ç - AltGr , c
    ê - AltGr Shift+> e

# installing/removing a particular package
sudo apt install nmap
sudo apt remove nmap
sudo apt purge nmap

# Updating package lists and then upgrading them. Can also upgrade individual packages by name
sudo apt update
sudo apt upgrade

# List all packages, grep for a particular package. Version is also displayed.
$ apt list
$ apt list | grep <packageName>
$ apt list --installed
$ apt list --upgradeable

# Search for package in available packages, show information about a package - dependencies, installation size, package source
$ apt search package_name
$ apt show package_name

# seeing a list of installed packages
dpkg -l | less
dpkg -l <packageName>

#To check whether a package is installed or not:

dpkg -l {package_name}
dpkg -l vlc
dpkg -l | grep vlc

Show the location where the package is installed. The "-S" (capital S) stands for "search"

sudo dpkg -S {package_name}
sudo dpkg -S skype


# Installing a local package 
sudo dpkg -i package_file.deb

uname -a # for all information regarding the kernel version
uname -r # for the exact kernel version
lsb_release -a # for all information related to the Ubuntu version,
lsb_release -r # for the exact version
sudo fdisk -l # for partition information with all details.

dpkg -l | grep linux-image # displays all installed kernels
dpkg -l | tail -n +6 | grep -E 'linux-image-[0-9]+'

apt-mark showmanual 'linux-image-.*' # show manually installed kernels
apt-mark showauto 'linux-image-.*'   # show auto installed kernels

sudo apt --purge autoremove # remove unused old kernels (only removes auto installed kernels I think)

# Get the initial flavour
cat /proc/version

# Then followup with specific commands

# Red Hat for example
cat /etc/redhat-release

# Debian
cat /etc/debian_version

# or in general :
cat /etc/*-release
# Also you could use the following command
cat /etc/issue

sudo lshw -class memory

# Results look like this for 2 RAM slots (Banks) which are both used:

    *-memory
         description: System Memory
         physical id: 4d
         slot: System board or motherboard
         size: 16GiB
       *-bank:0
            description: SODIMM DDR4 Synchronous Unbuffered (Unregistered) 2400 MHz (0.4 ns)
            product: HMA81GS6AFR8N-UH
            vendor: Hynix Semiconductor (Hyundai Electronics)
            physical id: 0
            serial: 2C9D672E
            slot: DIMM A
            size: 8GiB
            width: 64 bits
            clock: 2400MHz (0.4ns)
       *-bank:1
            description: SODIMM DDR4 Synchronous Unbuffered (Unregistered) 2400 MHz (0.4 ns)
            product: HMA81GS6AFR8N-UH
            vendor: Hynix Semiconductor (Hyundai Electronics)
            physical id: 1
            serial: 2C9D6723
            slot: DIMM B
            size: 8GiB
            width: 64 bits
            clock: 2400MHz (0.4ns)

# See what process send/receives most packets
netstat -anp --inet

# Interface is connected if link=yes
$ sudo lshw -c network | egrep 'description|name|link'

#Monitor the traffic on connected interfaces:
$ watch ip -s link

# Commands to use - NB I have more space on /home than elsewhere but can put anywhere

# Use ONE of the following to create the swap file - I used second way
sudo fallocate -l 10G /home/swapfile # this is the quick and easy way
sudo dd if=/dev/zero of=/home/swapfile bs=1024 count=10485760 # this is more portable

# setup the swap file for use (permissions to root for using it)
sudo mkswap /home/swapfile
sudo chmod 600 /home/swapfile
sudo swapon /home/swapfile

# Add to fstab to make the change permanent
sudo vim /etc/fstab
#Add this line
/home/swapfile swap swap defaults 0 0

sudo systemctl stop snapd.service
sudo mv /var/lib/snapd /home/snapd
sudo ln -s /home/snapd /var/lib/snapd
sudo systemctl start snapd.service

##############################################################################
# Take Care this section may break the System !!!
##############################################################################
##Move snap folder to Home instead of root.
#Create the directory : you can change the location
mkdir /home/$USER/snap/snapd

#Copy the data
sudo rsync -avzP /var/lib/snapd/  /home/$USER/snap/snapd/

#Do backups
sudo mv /var/lib/snapd /var/lib/snapd.bak
sudo cp /etc/fstab /etc/fstab.bak

#Change fstab (Change $USER with your name or change the path totally)
echo "/home/$USER/snap/snapd /var/lib/snapd none bind 0 0" | sudo tee -a /etc/fstab

#remount fstab Or reboot.
sudo mkdir /var/lib/snapd
sudo mount -a

if ls  /var/lib/snapd/ | grep snaps
then
    echo "Re-mounting snapd folder is done successfully. !!!!"
    sudo rm -rf /var/lib/snapd.bak
else
    echo "WARNING : Re-mounting snapd folder failed, please revert !!!!! "
    echo "WARNING : Re-mounting snapd folder failed, please revert !!!!! "
    echo "WARNING : Re-mounting snapd folder failed, please revert !!!!! "
    echo "WARNING : Re-mounting snapd folder failed, please revert !!!!! "
    echo "WARNING : Re-mounting snapd folder failed, please revert !!!!! "

    # Trying to revert automatically
    sudo cp /etc/fstab.bak /etc/fstab

sudo update-alternatives --display java
sudo update-alternatives --config java

# Searching for JAVA_HOME setting
$ grep JAVA_HOME  ~/.bashrc_custom ~/.bash_login ~/.profile ~/.bashrc
$ grep JAVA_HOME /etc/environment /etc/bash.bashrc /etc/profile.d/* /etc/profile

...Found it in /etc/environment

  # List crons
  crontab -l 
  # edit crontab for current user
  crontab -e

# Useful commands

- On the command prompt, type screen.
- Run the desired program.
- Use the key sequence Ctrl-a + Ctrl-d to detach from the screen
    session.
- Reattach to the screen session by typing screen -r.

# Create new window 0-9

- Ctrl+a c Create a new window (with shell)
- Ctrl+a " List all window
- Ctrl+a 0 Switch to window 0 (by number )
- Ctrl+a A Rename the current window

# Navigating

- Ctrl+a n switch to next window
- Ctrl+a p switch to previous window

- Ctrl+a S Split current region horizontally into two regions
- Ctrl+a | Split current region vertically into two regions
- Ctrl+a tab Switch the input focus to the next region
- Ctrl+a Ctrl+a Toggle between the current and previous region
- Ctrl+a Q Close all regions but the current one
- Ctrl+a X Close the current region

# detach and reattach

- Ctrl+a d - detach from Linux Screen Session
- screen -r - resume screen session
- screen -r 10835 - resume for screen session 10835 (see screen -ls
    below)

# list all screens running on the machine

- screen -ls

# How-to:
  # Ctrl+z to interrupt, 
  bg #to put in background, 
  jobs # to see job number, 
  disown %<jobNumber> # get the <jobNumber> value from jobs command

# Start a session with a name 
$ tmux new -s <session_name>

# For TMux start giving a command by Ctrl+b then the command, similar to Ctrl+A for Screen

# Create a new window/tab
$ c

# List windows/tabs 
$ w

# Navigate windows - Next, Previous, numbered window
$ N
$ P
$ 0-9

# Split window
$ % # vertical split
$ \" # horizontal split
$ up,down,left,right # navigate splits

# Attach/Detach from sessions
$ D # detaches from session but leaves it running in the background
$ tmux attach-session -t <session_name> # e.g. geek-1

# List running sessions
$ S

# Delete everything between BEGIN and END lines for all *.txt files, creating a backup .bak for each one and modifying the original
sed -i.bak '/BEGIN/,/END/d' *.txt

# same thing with another string
sed -i.bak2 '/EditStuff/,/EditStuffFinish/d' *.err

# Finds end of line with $, then adds ":80" to it
sed -n 's/$/:80/' ips.txt > new-ips.txt

# See the list of crash reports ll /var/crash/

total 988 drwxrwsrwt 2 root whoopsie 4096 Jan 17 15:55 ./ drwxr-xr-x 15
root root 4096 Jul 25 2018 ../ -rw-r\--r\-- 1 kernoops whoopsie 2648 Jan
15 11:30 linux-image-4.18.1-041801-generic.220862.crash -rw-r\-\-\-\-- 1
root whoopsie 28316 Jan 17 10:57
\_usr_bin_landscape-package-changer.0.crash -rw-r\-\-\-\-- 1 dcostello
whoopsie 967043 Jan 17 15:55 \_usr_bin_onedrive.1000.crash

# Remove if it's okay
sudo rm /var/crash/*

curl -s -o /dev/null -D - --location --request POST 'https://somesite.com' \
--data '@somefile.json'

# useful options
-i, --include # include HTTP Headers in the output

# Move multiple files/directories to a directory
mv -t <DESTINATION> <source1> <source2> ......

$ lscpu

# example output
Architecture:        x86_64
CPU op-mode(s):      32-bit, 64-bit
Byte Order:          Little Endian
CPU(s):              8
On-line CPU(s) list: 0-7
Thread(s) per core:  2
Core(s) per socket:  4
Socket(s):           1
NUMA node(s):        1
Vendor ID:           GenuineIntel
CPU family:          6
Model:               142
Model name:          Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
Stepping:            10
CPU MHz:             3595.397
CPU max MHz:         4200.0000
CPU min MHz:         400.0000
BogoMIPS:            4224.00
Virtualization:      VT-x
L1d cache:           32K
L1i cache:           32K
L2 cache:            256K
L3 cache:            8192K
NUMA node0 CPU(s):   0-7
Flags:               fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp flush_l1d

  # Simple example of copy to remote
  scp somefile.txt myuser@myhost:~/somedirectory

# Recursive copy
cp -r <pathToTarget> <pathToDest>

# Copy multiple named files
cp ./{File1,File2,File3} <pathToDest>

  # Remote rsync
  rsync -a ~/dir1 username@remote_host:destination_directory

# TOP - log out to a file in batch mode -n iterations -d interval in secs -o order by field -b batch mode
top -n 10 -d 2 -o %CPU -b \> \~/dcTOP.txt

# To limit output can run top once interactively, limit number of
processes with n then W to write a user config file

# VMSTAT - gives memory and cpu info - the command below will run it with a timestamp, format the memory in MB and repeat every 30s for 500 repetitions (enough for 2hrs of info)
vmstat -t -S M 30 500 2>&1 | tee vmstats.txt

# Tar and zip
$ tar zcpfv dokuwiki-backup.tar.gz /path/to/dokuwiki

# unzip
$ tar zxvf dokuwiki-xxxx-xx-xx.tgz


# Example of finding and then tar-ing files
$ find Interfaces/ -name "*DC003*" -mmin -20 -print0 | tar -czvf ~/QF_FBA_Weight/backup.tar.gz --null -T -

# Example of un-taring and creating a target directory for the -C option ($_ is a special bash variable to get the output of the previous command)
$ mkdir -p /target/dir && tar -C $_

tar -xzf someArchive.tar.gz --one-top-level

$ sudo tcpdump -v -i any -c250 -nn host 10.56.208.4

# read verbose on any network interface, 250 messages, filter by host

# Create a dir, if the parent directories don't exist, create them too
$ mkdir -p /target/dir 

# Can create multiple directories and multiple levels of dirs too
$ mkdir -p /target/{sub1, sub2}/{subsub1, subsub2}

    # basic command to see addresses in colour
    ip -c a

# install
sudo apt-get install ncdu

# run with
ncdu

du -sh .

# to find just in the current directory per folder
du -h --max-depth=1

df

# netstat looking for a particular port number
netstat -laptenu | grep 20005

# does a lookup on DNS
nslookup <ip address>

# hostname doesn't always work
hostname -a <ip address>

    chmod ugo+rwx filename

    # simply make a file executable
    chmod +x filename.sh

# find jpg files in the current directory
find . -name '*.jpg'

# find in the current directory files modified in the last minute 
find . -maxdepth 1 -mmin -1

# find with date details and ordering by date 
find . -mmin -15 -printf "%T@ %Tc %p\n" | sort -n

# find .log files and then copy them to ~/someDir
find . -name "*.log" -mmin -45 -exec cp {} ~/someDir \;

# find dirs without a certain filename 
find base_dir -mindepth 2 -maxdepth 2 -type d '!' -exec test -e "{}/cover.jpg" ';' -print

# find and delete - good for deleting lots of files where rm stops working 
find . -name "simulation.log" -delete

# find with multiple matches (from a bash script)
list_of_files="$(find . -type f -name "filename1-*" -or -name "*-filename2")"

# find files where we have .blah and a corresponding .blah.log - finds cases of missing .log files and counts them
find . -name "*.blah" '!' -exec test -e "{}.log" ';' -print | wc -l

# some more examples 
<https://geekflare.com/linux-find-commands/>

# Install if not available on your machine
# List all files and directories including hidden files (-a), to 2 levels with size of each file 
tree -a -L 2 -s

# Create a symbolic link
ln -s /path/to/original /path/to/symlink

# List all symbolic links in a directory
ls -l | grep ^l

# List all symbolic links in a directory and their targets
ls -l | grep ^l | awk '{print $9 " -> " $11}'

# Remove a symbolic link
rm /path/to/symlink
unlink /path/to/symlink

# count the number of files in a dir 
ls -l | wc -l

grep [options] [pattern] [file]

#If you have the output "Binary file (standard input) matches" whengrep something you know is text,
# you can force grep to treat everything as text using -a
grep -a SomeString log.txt

# other forms of this option: -a, --text, '--binary-files=text'

# example of counting the occurrences
grep -o SOMESTRING myFile.txt | wc -l

find .  -name "*.edi" -exec  grep  -H -E -o -c  "SomeString"  {} \;
find .  -name "*.edi" -exec  grep  -H -E -o -c  "SomeString"  {} \;
# Find files of a particular name not containing a string - bit at the end is to look for count 0
find .  -name "*.edi" -exec  grep  -H -E -o -c  "SomeString"  {} \; | grep 0

# This is a really nice way to find files of a particular type containing WITHTHISSTRING but not containing NOTTHISSTRING
# The inner grep feeds the filenames of the matches into the outer grep
# -l is to suppress the normal output which includes the matching string
# -L is to find things that DON'T match
grep -rL "NOTTHISSTRING" $(grep -rl WITHTHISSTRING '.' --include=*.cpp)

# Example for finding a lib with a certain symbol 
for lib in `find . -name "*.so"` ; do  grep "someSymbol" $lib >/dev/null; if [ $? -eq 0 ]; then echo $lib; fi  done

# Finding a process with grep and filtering your grep from the result
ps aux | grep some_process | grep -v grep

# Example using grouping with alternative matches
$ grep -E "(GPL|General Public License)" GPL-3

Output:
The *GNU General Public License* is a free, copyleft license for...
Developers that use the GNU *GPL* protect your rights with two steps: ...
  

#once the repos are setup - install docker-ce
sudo apt-get install docker-ce

# These commands will download the docker images and run a container
sudo docker run hello-world
sudo docker run -it ubuntu bash

## List Docker CLI commands
docker
docker container --help

## Display Docker version and info
docker --version
docker version
docker info

## Execute Docker image
docker run hello-world

## List Docker images
docker image ls

## List Docker containers (running, all, all in quiet mode)
docker container ls
docker container ls --all
docker container ls -aq

    docker-compose stop # stop container
    docker-compose down -v # stop and remove container

# Cutting, copying and pasting lines
yy # copy
2yy # copy 2 lines
dd # cut

p # paste after
P # paste before

# Finding
/searchstring

# Navigating within less
g - jump to beginning
G - jump to end

/someString - search for "someString" and highlight occurrences n next
occurrence N prev occurrence