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abs_path(){
# Transforms any path, including windows paths, given as parameter, to absolute path.
# Expands ~, ~-, \  etc.
# Exitcode: 0 (output to stdout) if path exists, 1 (outout to stderr) otherwise.

  local path="${1}"
# Windows to Unix path [if operand is Unix path, then wslpath outputs to stderr]
  local buffer=$(wslpath -u "${path}" 2>/dev/null); path="${buffer:-"${path}"}"
  eval path="${path}"  # Remove backslash, Tilde expansion etc.
  [[ "${path}" != /* ]] && path="${PWD}/${path}"

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Remove old commits from local repo

Shallow fetch from self:

Keep only last n commits--

git fetch --depth=<n-1> . <branch>

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The readline prompt [read -p] is sent to stderr

The prompt for interactive bash is also sent to stderr. See POSIX mandate below

Source : https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html

PS1 :: Each time an interactive shell is ready to read a command, the value of this 
variable shall be subjected to parameter expansion and written to standard error.

NOTE (source- Bash reference manual):

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# This function dumps the input stream to the path given as parameter.
# If PATH gets unlinked by another (cooperative) process, it creates a new file at PATH and continues dump
# Provide a lockfile as the 2nd positional parameter. This is needed so that another process doesn't remove PATH
# when it is being written to.

stream_dump(){
  declare -x path="${1}"
  local lock="${2}"
  local timeout="1" # Interval for polling $path
  declare -x line

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# First run the following 2 lines in your interactive bash attached to a controlling terminal
export bashpidfile="/tmp/bashpid" # File that stores the bash pid
export PROMPT_COMMAND='echo $$ > $bashpidfile' # Or, replace $$ with $BASHPID

# From another terminal do the following
### TPGID gives fg proc group on the tty the process is connected to, or -1 if the process is not connected to a tty
fgpg=$(ps --pid $(awk NR==1 $bashpidfile) -o tpgid=)

# Send signal SIG to all foreground processes to emulate user Ctrl- inputs
# Ctrl-C: INT, Ctrl-Z: TSTP, Ctrl-\: QUIT

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### Source me
readline_cword(){
  # Gives current word of Bash readline, viz. the word where the insertion point/cursor is currently at
  set -- ${READLINE_LINE}
  local length=${#1}
  while ((length < READLINE_POINT)); do
    shift
    length+=${#1}
  done
  echo -n "${1}"

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List of freemium port-forwarding services

Useful for accessing a computer that does not have a public IP address, over the internet. The machine can be behind multiple firewalls and NATs.

1. Global socket or gsocket
2. localhost.run
3. github.com/jpschroeder/pipe-to-me
4. getuplink.de
5. localtunnel.me
6. localXpose.io

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ngrok how to (tested with Linux and WSL)

1. Download

2. Sign-up (email is not verified!)

3. Get your authtoken from the dashboard

./ngrok authtoken

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How to use streambin for event-based workflow : pubsub (publish/subscribe) model

Push based workflow is more efficient than repeated pulls (polling). Thankfully, there is currently a free service for the same which is easy to use : https://streambin.pbedat.de/. There is also emitter.io and free, public MQTT brokers such as broker.hivemq.com (list).

1. Create a unique channel-key - it may be the hash of your email id or the hash of your MAC address, or may even be the fingerprint of freshly generated private-public keypair.

2. url="https://streambin.pbedat.de/streams/${channel_key}"

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while num=$(read -re -p "type: "|& tee /dev/tty|fold -w "$(tput cols)"|wc -l); do tput cuu $num;tput ed; done