File: catl.sh
   1 #!/bin/sh
   2 
   3 # The MIT License (MIT)
   4 #
   5 # Copyright © 2020-2025 pacman64
   6 #
   7 # Permission is hereby granted, free of charge, to any person obtaining a copy
   8 # of this software and associated documentation files (the “Software”), to deal
   9 # in the Software without restriction, including without limitation the rights
  10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11 # copies of the Software, and to permit persons to whom the Software is
  12 # furnished to do so, subject to the following conditions:
  13 #
  14 # The above copyright notice and this permission notice shall be included in
  15 # all copies or substantial portions of the Software.
  16 #
  17 # THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23 # SOFTWARE.
  24 
  25 
  26 # catl [options...] [filepaths...]
  27 #
  28 # Unlike `cat`, conCATenate Lines ensures no lines across inputs are
  29 # accidentally joined, since all lines it outputs end with line-feeds,
  30 # even when the original files don't.
  31 #
  32 # The only option available is to show this help message, using any of
  33 # `-h`, `--h`, `-help`, or `--help`, without the quotes.
  34 
  35 
  36 case "$1" in
  37     -h|--h|-help|--help)
  38         awk '/^# +catl /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  39         exit 0
  40     ;;
  41 esac
  42 
  43 # show all non-existing files given
  44 failed=0
  45 for arg in "$@"; do
  46     if [ "${arg}" = "-" ]; then
  47         continue
  48     fi
  49     if [ ! -e "${arg}" ]; then
  50         printf "\e[31mno file named \"%s\"\e[0m\n" "${arg}" > /dev/stderr
  51         failed=1
  52     fi
  53 done
  54 
  55 # in case of errors, avoid showing an empty screen
  56 if [ "${failed}" -gt 0 ]; then
  57     exit 1
  58 fi
  59 
  60 awk '{ print; fflush() }' "$@"