Replacing to a ASCII character.

rep2ascii.sh

#!/bin/bash --posix
# -*- coding:utf-8 -*-

# === Coding shell scripting Memo ==============================================
# ${<name>#<pattern>} :: matching delete with shortest by forword.
# ${<name>##<pattern>} :: matching delete with longest by forword.
# ${<name>%<pattern>} :: matching delete with shortest by backword.
# ${<name>%%<pattern>} :: mathing delete with longest by backword.
# ${<name>/<before>/<after>} :: replace only first matching.
# ${<name>//<before>/<after>} :: replace all matching.
# ${<name>:-<value>} :: if no yet set value, return value.
# ${<name>:=<value>} :: if no yet set value, return value and set.

# ". <shell script>" is to keep current shell and take over environment.

# === Initialize shell environment =============================================
#set -u                        # Just stop undefined values.
#set -e                        # Just stop error.
#set -x                        # Debug running command.

umask 0022
export LC_ALL=C
export LANG=C
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/bin:${PATH+:}${PATH-}"
type command >/dev/null 2>&1 && type getconf >/dev/null 2>&1 &&
export PATH="$(command -p getconf PATH):${PATH}"
export UNIX_STD=2003          # to make HP-UX conform to POSIX

# === Define the functions for printing usage and error message ================
usage_and_exit(){
    cat <<-"USAGE" 1>&2
# About

Replacing to a ASCII character.

# Usage

## Command

rep2ascii.sh [option]

## Options

- -h |--help |--version
  + This help.

# Version

2021-07-31 0.01

# LICENSE

[CC0(Public domain)](https://creativecommons.org/publicdomain/zero/1.0/legalcode)

# Author

2021 TD

USAGE

    exit 1
}

error_exit() {
    ${2+:} false && echo "${0##*/}: $2" 1>&2

    exit "$1"
}

# === Initialize parameters ====================================================
SED_LF=$(printf '\\\n_')
SED_LF=${SED_LF%_}
IN_FILE=''

# === Confirm that the required commands exist =================================
# --- cURL or Wget (exsample)
#if   type curl    >/dev/null 2>&1; then
#  CMD_CURL='curl'
#elif type wget    >/dev/null 2>&1; then
#  CMD_WGET='wget'
#else
#  error_exit 1 'No HTTP-GET/POST command found.'
#fi

# === Print usage and exit if one of the help options is set ===================
case "$# ${1:-}" in
    '1 -h'|'1 --help'|'1 --version') usage_and_exit;;
esac

# === Read options =============================================================
while :; do
    case "${1:-}" in
        --|-)
            break
            ;;
        --*|-*)
            error_exit 1 'Invalid option'
            ;;
        *)
            break
            ;;
    esac
done

# === Require parameters check =================================================
# === Last parameter ===========================================================
case $# in
    0) :                             ;;
    1) IN_FILE=$1                    ;;
    *) error_exit 1 'Too many args.' ;;
esac
if   [ "_$IN_FILE" = '_' ] ||
         [ "_$IN_FILE" = '_-' ] ||
         [ "_$IN_FILE" = '_/dev/stdin' ] ||
         [ "_$IN_FILE" = '_/dev/fd/0' ] ||
         [ "_$IN_FILE" = '_/proc/self/fd/0' ]  ; then
    IN_FILE=''
elif [ -f "$IN_FILE" ] ||
         [ -c "$IN_FILE" ] ||
         [ -p "$IN_FILE" ]  ; then
    [ -r "$IN_FILE" ] || error_exit 1 'Cannot open the file: '"$IN_FILE"
else
    usage_and_exit
fi
case "$IN_FILE" in ''|-|/*|./*|../*) :;; *) IN_FILE="./$IN_FILE";; esac

# === Define funcitons =========================================================
# === Main routine =============================================================
cat ${IN_FILE:+"$IN_FILE"} |\
    sed "s/。/./g" |\
    sed "s/、/,/g" |\
    sed "s/，/,/g" |\
    sed "s/．/./g" |\
    sed "s/：/:/g" |\
    sed "s/；/;/g" |\
    sed "s/！/!/g" |\
    sed "s/？/?/g" |\
    sed "s/（/(/g" |\
    sed "s/）/)/g" |\
    sed "s/｛/{/g" |\
    sed "s/｝/}/g" |\
    sed "s/＿/_/g" |\
    sed "s/’/\'/g" |\
    sed "s/‘/\'/g" |\
    sed "s/’/\'/g" |\
    sed 's/“/"/g' |\
    sed 's/”/"/g' |\
    sed "s/「/\'/g" |\
    sed "s/」/\'/g" |\
    sed "s/『/\"/g" |\
    sed "s/』/\"/g" |\
    sed "s/〔/[/g" |\
    sed "s/〕/]/g" |\
    sed "s/［/[/g" |\
    sed "s/］/]/g" |\
    sed "s/【/</g" |\
    sed "s/】/>/g" |\
    sed "s/〈/</g" |\
    sed "s/〉/>/g" |\
    sed "s/＜/</g" |\
    sed "s/＞/>/g" |\
    sed "s/《/<</g" |\
    sed "s/》/>>/g" |\
    sed "s/～/~/g" |\
    sed "s/―/-/g" |\
    sed "s/ー/-/g" |\
    sed "s/＝/=/g" |\
    sed "s/％/%/g" |\
    sed "s/＃/#/g" |\
    sed "s/＆/\&/g" |\
    sed "s/＊/*/g" |\
    sed "s/＠/@/g" |\
    sed "s:／:/:g" |\
    sed "s:＼:\\\\:g" |\
    sed "s:∥://:g" |\
    sed "s/｜/|/g" |\
    sed "s/＋/+/g" |\
    sed "s/－/-/g" |\
    sed "s/　/ /g" |\
    sed "s/	/    /g" |\
    sed "s/Ａ/A/g" |\
    sed "s/Ｂ/B/g" |\
    sed "s/Ｃ/C/g" |\
    sed "s/Ｄ/D/g" |\
    sed "s/Ｅ/E/g" |\
    sed "s/Ｆ/F/g" |\
    sed "s/Ｇ/G/g" |\
    sed "s/Ｈ/H/g" |\
    sed "s/Ｉ/I/g" |\
    sed "s/Ｊ/J/g" |\
    sed "s/Ｋ/K/g" |\
    sed "s/Ｌ/L/g" |\
    sed "s/Ｍ/M/g" |\
    sed "s/Ｎ/N/g" |\
    sed "s/Ｏ/O/g" |\
    sed "s/Ｐ/P/g" |\
    sed "s/Ｑ/Q/g" |\
    sed "s/Ｒ/R/g" |\
    sed "s/Ｓ/S/g" |\
    sed "s/Ｔ/T/g" |\
    sed "s/Ｕ/U/g" |\
    sed "s/Ｖ/V/g" |\
    sed "s/Ｗ/W/g" |\
    sed "s/Ｘ/X/g" |\
    sed "s/Ｙ/Y/g" |\
    sed "s/Ｚ/Z/g" |\
    sed "s/ａ/a/g" |\
    sed "s/ｂ/b/g" |\
    sed "s/ｃ/c/g" |\
    sed "s/ｄ/d/g" |\
    sed "s/ｅ/e/g" |\
    sed "s/ｆ/f/g" |\
    sed "s/ｇ/g/g" |\
    sed "s/ｈ/h/g" |\
    sed "s/ｉ/i/g" |\
    sed "s/ｊ/j/g" |\
    sed "s/ｋ/k/g" |\
    sed "s/ｌ/l/g" |\
    sed "s/ｍ/m/g" |\
    sed "s/ｎ/n/g" |\
    sed "s/ｏ/o/g" |\
    sed "s/ｐ/p/g" |\
    sed "s/ｑ/q/g" |\
    sed "s/ｒ/r/g" |\
    sed "s/ｓ/s/g" |\
    sed "s/ｔ/t/g" |\
    sed "s/ｕ/u/g" |\
    sed "s/ｖ/v/g" |\
    sed "s/ｗ/w/g" |\
    sed "s/ｘ/x/g" |\
    sed "s/ｙ/y/g" |\
    sed "s/ｚ/z/g" |\
    sed "s/０/0/g" |\
    sed "s/１/1/g" |\
    sed "s/２/2/g" |\
    sed "s/３/3/g" |\
    sed "s/４/4/g" |\
    sed "s/５/5/g" |\
    sed "s/６/6/g" |\
    sed "s/７/7/g" |\
    sed "s/８/8/g" |\
    sed "s/９/9/g" |\
    sed "s/…/.../g" |\
    sed "s/©/(C)/g" |\
    sed "s/${SED_LF}${SED_LF}${SED_LF}*/${SED_LF}${SED_LF}/g"
# === End shell script =========================================================
exit 0