gistfile1.txt

exec 73>&- 74<&- 74> >(perl -nE 'say "...$_..."') 73> >(LANG=C exec stdbuf -o0 perl -nE 'say ,,,$_,,,' >&74 2>&1)

function perl::start {
  read TMPDIR < <(/usr/bin/mktemp -d /dev/shm/conn_shell_XXXXXXX)
  mkfifo $TMPDIR/perl
  nextFd PERLIN
  echo $PERLIN
  eval "exec $PERLIN> >(LANG=C exec stdbuf -o0 -i0 perl -pE '\$_="1\n\r"' >$TMPDIR/perl 2>&1)"
  nextFd PERLOUT
  echo $PERLOUT
  eval "exec $PERLOUT<$TMPDIR/perl"
  rm -v $TMPDIR/perl
  rmdir -v $TMPDIR
}
function perl::perl { [ -z "$PERLIN" -o -z "$PERLOUT" ] && return; local VAR=$1; shift; echo -e "$*" 1>&$PERLIN && IFS= read -r -d $'\r' -u $PERLOUT $VAR; }
function perl::stop { [ -n "$PERLIN" -a -n "$PERLOUT" ] && eval "exec $PERLIN>&- $PERLOUT<&-"; true; }
perl::tput() { echo -e "$1\ncr" 1>&$PERLIN && IFS= read -r -d $'\r' -u $PERLOUT $2; }

function ln::start {
  local fd=3;
  while [ -e /dev/fd/$fd ]; do ((fd++)); done
  eval "exec $fd<> >(LANG=C exec stdbuf -o0 perl -n -E 'chomp;@_=split/\\t/;say link \$_[0], \$_[1]' &>/dev/null)";
  echo $fd
}
function ln::ln { eval 'echo -e "$2\t$3" 1>&'$1; }
function ln::stop { eval "exec $1>&-"; }

function varcmd::one {
  [ -z "$2" ] && { echo "usage: $FUNCNAME var command ..."; return 1; }
  local fd=3 VAR=$1; shift
  while [ -e /dev/fd/$fd ]; do ((fd++)); done
  local shm=/dev/shm/conn_shell_$$_${fd}
  mkfifo $shm
  eval "exec $fd<> $shm"
  unlink $shm
  eval '"$@" 1>&'$fd
  mapfile -u$fd -n1 -t $VAR
  eval "exec $fd>&-"
}
function varcmd::start {
  local __varcmd_fd=3; while [ -e /dev/fd/$__varcmd_fd ]; do ((__varcmd_fd++)); done
  # ALT: find -L /dev/fd/ -mindepth 1 -maxdepth 1 -type d 2>/dev/null
  local shm=/dev/shm/conn_shell_$$_${__varcmd_fd}
  mkfifo $shm
  eval "exec $__varcmd_fd<> $shm"
  unlink $shm
  echo "FD: $__varcmd_fd"
}
function varcmd {
  [ -z "$3" ] && { echo "usage: $FUNCNAME fd var command ..."; return 1; }
  local FD=$1 VAR=$2; shift; shift
  test -e /dev/fd/$FD || return 255
  eval '"$@" 1>&'$FD
  mapfile -u$FD -n1 -t $VAR
}
function varcmd::end {
  [ -z "$1" ] && { echo "usage: $FUNCNAME fd"; return 1; }
  eval "exec $1>&-"
}

tputConnector() {
  read TMPDIR < <(/usr/bin/mktemp -d /dev/shm/conn_shell_XXXXXXX)
  mkfifo $TMPDIR/tput
  nextFd TPUTIN
  eval "exec $TPUTIN> >(LANG=C exec stdbuf -o0 tput -S - >$TMPDIR/tput 2>&1)"
  nextFd TPUTOUT
  eval "exec $TPUTOUT<$TMPDIR/tput"
  rm $TMPDIR/tput
  rmdir $TMPDIR
}
myTput() { echo -e "$1\ncr" 1>&$TPUTIN && IFS= read -r -d $'\r' -u $TPUTOUT $2; }

gistfile2.txt

#!/bin/bash

# $ $0 forks
# $ $0 1fork

# https://unix.stackexchange.com/a/521120

function forks {
  for ((i=0; i<256; i++)); do
      echo -n '  '
      tput setab $i
      tput setaf $(( ( (i>231&&i<244 ) || ( (i<17)&& (i%8<2)) ||
          (i>16&&i<232)&& ((i-16)%6 <(i<100?3:2) ) && ((i-16)%36<15) )?7:16))
      printf " C %03d " $i
      tput op
      (( ((i<16||i>231) && ((i+1)%8==0)) || ((i>16&&i<232)&& ((i-15)%6==0)) )) &&
          printf "\n" ''
  done
}

# ... Then, because I hate runnig more than 200 forks in a little script, I wrote this:

function one_fork {
  # Connector fifos directory

  fd=3
  # find next free fd
  nextFd() { while [ -e /dev/fd/$fd ];do ((fd++)) ;done;printf -v $1 %d $fd;}

  tputConnector() {
    read TMPDIR < <(/usr/bin/mktemp -d /dev/shm/conn_shell_XXXXXXX)
    mkfifo $TMPDIR/tput
    nextFd TPUTIN
    eval "exec $TPUTIN> >(LANG=C exec stdbuf -o0 tput -S - >$TMPDIR/tput 2>&1)"
    nextFd TPUTOUT
    eval "exec $TPUTOUT<$TMPDIR/tput"
    rm $TMPDIR/tput
    rmdir $TMPDIR
  }
  myTput() { echo -e "$1\ncr" 1>&$TPUTIN && IFS= read -r -d $'\r' -u $TPUTOUT $2; }
  tputConnector

  myTput op op
  myTput "setaf 7" grey
  myTput "setaf 16" black
  fore=("$black" "$grey")
  for ((i=0; i<256; i++)) ;do
    myTput "setab $i" bgr
    printf "  %s%s  %3d  %s" "$bgr" "${fore[ i>231 && i<244||(i<17)&& (i%8<2)||
      (i>16&&i<232)&&((i-16)%6*11+(i-16)/6%6*14+(i-16)/36*10)<58
      ? 1 : 0 ]}" $i "$op"
    (( ((i<16||i>231) && ((i+1)%8==0)) || ((i>16&&i<232)&& ((i-15)%6==0)) )) &&
      printf "\n" ''
  done
}

# With only 1 fork! Same result, but approx 10x faster!
# If first script run in ~1.12 second on my desk, they take upto ~47.4 seconds on my raspberry-pi!!
# While second script run in ~0.11 second on my desk and ~4.97 seconds on my raspberry.

case $1 in
  forks) forks;;
  1fork) one_fork;;
esac

gistfile3.txt

function backup-mpfs {
  [ -n "$1" ] || backup::✗ "usage: $FUNCNAME mount-point" || return
  local mp="$1"; shift
  #[[ $mp =~ ^/dev/ ]] && mp=$(grep ^$mp /proc/mounts | cut -f2 -d' ')
  #mp=$(stat -c%m $mp)
  local DATE=$(date +"%Y%m%dT%H%M%S")
  local SNAPSHOTS=$mp/.snapshots; mkdir -pv $SNAPSHOTS
  local FILESTORE=$mp/.filestore; mkdir -pv $FILESTORE
  rsync -vaziHl --link-dest "$mp" --exclude ".snapshots" --exclude ".filestore" "$mp" "$SNAPSHOTS/$DATE"
  local sha staging file dirname i
  backup::varcmd::start; local fd=$__backup_fd
  trap "backup::varcmd::end $fd" RETURN
  while read i; do
    test ! -e "$i" -o -L "$i" -o -d "$i" && continue
    backup::varcmd $fd sha sha256sum "$i"
    sha=${sha:0:64}
    filestore=$FILESTORE/${sha:0:1}/${sha:0:2}/${sha:0:3}
    { 
      test -d "$filestore" || mkdir -pv "$filestore"
    } && {
      test -e "$filestore/$sha" || ln -v "$i" "$filestore/$sha"
    } && {
      ! backup::samefile "$i" "$filestore/$sha"
    } && {
      backup::samecontents "$i" "$filestore/$sha"
    } && {
      ln -fv "$filestore/$sha" "$i"
    };
    echo;
  done < <(find $SNAPSHOTS/$DATE -type f)
}

function backup::samefile {
  [ -e "$1" -a -e "$2" ] && [ $(stat -c%i "$1") == $(stat -c%i "$2")  ] && echo "samefile $1 => $2" && return 0
  return 1
}

function backup::samecontents {
  [ -e "$1" -a -e "$2" ] && [ $(stat -c%s "$1") == $(stat -c%s "$2") -a "$(head -c100 "$1")" == "$(head -c100 "$2")" -a "$(tail -c100 "$1")" == "$(tail -c100 "$2")" ] && echo "samecontents $1 ~~ $2" && return 0
  return 1
}

gistfile4.txt

GREEN="$(tput setaf 2)"
RED="$(tput setaf 1)"
RESET="$(tput setaf 0)"
err_color=("${GREEN}" "${RED}")
err_prompt=("✓" "✗")
PS1='\[${err_color[(($??1:0))]}\]${err_prompt[(($??1:0))]}\[${RESET}\] \[\033[01;33m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '

gistfile5.txt

function cd { if [ "$1" == -q ]; then shift; test -d "$1" || return; fi; builtin cd "$@"; echo $(pwd) > ${HISTFILE/bash_histories/pwd}; }
function history-file { echo $HISTFILE; }
function history-reconfig { history-config ; history-file ;}
function history-config {
  test -d ~/.bash_histories || mkdir ~/.bash_histories
  test -d ~/.pwd || mkdir ~/.pwd
  HISTCONTROL=ignoreboth
  HISTIGNORE="history:ls:pwd"
  HISTSIZE=10000
  HISTFILESIZE=
  HISTTIMEFORMAT="%F %T "
  LC_HISTFILE=${LC_HISTFILE/~}
  LC_HISTFILE=${LC_HISTFILE:1}
  HISTFILE=~/$(test -n "$TMUX" && tmux display -p ".bash_histories/#{host}-#{session_name}-#{window_index}-#{pane_index}" 2>/dev/null || echo ${LC_HISTFILE:-.bash_histories/$HOSTNAME})
  export LC_HISTFILE=$HISTFILE
  shopt -s histappend
  test -f ${HISTFILE/bash_histories/pwd} && cd -q "$(< ${HISTFILE/bash_histories/pwd})"
}
history-config

gistfile6.txt

set -g mouse on
bind -n WheelUpPane if-shell -F -t = "#{mouse_any_flag}" "send-keys -M" "if -Ft= '#{pane_in_mode}' 'send-keys -M' 'select-pane -t=; copy-mode -e; send-keys -M'"
bind -n WheelDownPane select-pane -t= \; send-keys -M
bind -n C-WheelUpPane select-pane -t= \; copy-mode -e \; send-keys -M
bind -T copy-mode-vi    C-WheelUpPane   send-keys -X halfpage-up
bind -T copy-mode-vi    C-WheelDownPane send-keys -X halfpage-down
bind -T copy-mode-emacs C-WheelUpPane   send-keys -X halfpage-up
bind -T copy-mode-emacs C-WheelDownPane send-keys -X halfpage-down

# To copy, left click and drag to highlight text in yellow, 
# once you release left click yellow text will disappear and will automatically be available in clibboard
# # Use vim keybindings in copy mode
setw -g mode-keys vi
# Update default binding of `Enter` to also use copy-pipe
unbind -T copy-mode-vi Enter
bind-key -T copy-mode-vi Enter send-keys -X copy-pipe-and-cancel "xclip -selection c"
bind-key -T copy-mode-vi MouseDragEnd1Pane send-keys -X copy-pipe-and-cancel "xclip -in -selection clipboard"

gistfile7.txt

$ cd $(mktemp -d /dev/shm/qaz.XXXXX) \
  exec $out>&- $in<&- ; \
  tmp=$(mktemp -u /dev/shm/abc.XXX); \
  mkfifo $tmp; \
  exec $out> >(LANG=C exec stdbuf -o0 -i0 perl -nE 'BEGIN{$|=1}eval $_' >$tmp); \
  exec $in<$tmp; \
  rm $tmp ; \
  TIMEFORMAT=%3R


$ date > date ; rm -f ? ?? ??? ; \
  time for i in {1..10000}; do \
    ln -v date $i; rm -v $i; \
  done | wc -l ; \
  time for i in {10001..20000}; do \
    echo "say link 'date', '$i'; say unlink '$i'" >&$out \
    && read -t 0.1 -r -u $in \
    && echo $REPLY \
    && read -t 0.1 -r -u $in \
    && echo $REPLY; \
  done | wc -l
20000
29.618
20000
0.461

$ date > date ; rm -f ? ?? ??? ; \
  time for i in {1..10}; do \
    ln -v date $i; rm -v $i; \
  done | wc -l ; \
  time for i in {11..20}; do \
    echo "say link 'date', '$i'; say unlink '$i'" >&$out \
    && read -t 0.1 -r -u $in \
    && echo $REPLY \
    && read -t 0.1 -r -u $in \
    && echo $REPLY; \
  done | wc -l
20
0.030
20
0.002

gistfile8.txt

# $ pack 'H*' 6162
# ab
function pack { perl -E '$/=undef; say join " ", pack($ARGV[0], $ARGV[1]||<STDIN>)' "$@"; }

# $ unpack 'H*' ab
# 6162
function unpack { perl -E '$/=undef; say join " ", unpack($ARGV[0], $ARGV[1]||<STDIN>)' "$@"; }

# $ unpack 'H*' abcdefghijklmnopqrstuvwxyz | pfold -b=2 -w=4 -l=8 
# 61 62 63 64  65 66 67 68  
# 69 6a 6b 6c  6d 6e 6f 70  
# 71 72 73 74  75 76 77 78  
# 79 7a 
function pfold { perl -spE 'BEGIN{$bd//=" ";$b//=2;$wd//="  ";$w//=4;$l//=16}s/(.{$b})/$1.(!$w||++$c%($w)?$bd:$wd).(!$l||$c%$l?"":$\/)/ge' -- "$@"; }

# $ unpack 'H*' abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz | grephex 48 6a6b
# 616263646566676869   6a6b   6c6d6e6f707172737475767778797a616263646566676869   6a6b   6c6d6e6f707172737475767778797a
function grephex { perl -pE "\$l=$1;\$l=length(\$_)-length(q($2)) if $1>length(\$_)-length(q($2));s/(.*?)(.{0,$1})?($2)(.{0,$1})?(.*?)/(\$1?'...':'').\$2.qq(   \\e[31m\$3\\e[0m   \$4).(\$5?'...':'')/eg"; }

# $ seq 1 10 | pivot 5 :
# 1:2:3:4:5
# 6:7:8:9:10
function pivot { printf -v dashes -- '- %.0s' $(eval echo {1..$1}); paste -d"${2:- }" $dashes; }

# $ echo 123 | printfp "%05d\n"
# 00123
function printfp { exec {fd}<&0; readarray -t -u $fd var; printf ${1:-%s\n} "${var[@]}"; }

function random_chunks { A=$1 P=$2 S=$3 C=$4 perl -nE 'BEGIN{$|=1;srand;our $q=0;$SIG{ALRM}=sub{$q=$ENV{C}+1 and say "  ::" and alarm($ENV{A})};alarm($ENV{A})}alarm($ENV{A}) if $.<$ENV{S}+1||$q==1;$q-- if $q>0;do{alarm(0);print} if($.<$ENV{S}||$q||($ENV{P} and !(int(rand(100/$ENV{P}))) and $q=$ENV{C} and say "  :"))'; }
[ $# -eq 4 ] && random_chunks "$@"