File: tcatl.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 # tcatl [options...] [filepaths...]
  27 #
  28 # Unlike `cat`, Titled conCATenate Lines ignores leading UTF-8 BOMs, trailing
  29 # carriage-returns on all lines, and ensures no lines across inputs are
  30 # accidentally joined, since all lines it outputs end with line-feeds, even
  31 # when the original files don't. It also highlights the filename, before
  32 # emitting its lines.
  33 #
  34 # The only option available is to show this help message, using any of
  35 # `-h`, `--h`, `-help`, or `--help`, without the quotes.
  36 
  37 
  38 # handle help options
  39 case "$1" in
  40     -h|--h|-help|--help)
  41         awk '/^# +tcatl /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  42         exit 0
  43     ;;
  44 esac
  45 
  46 awk '
  47     FNR == 1 {
  48         # highlight current filename
  49         printf "\x1b[7m%s\x1b[0m\n", FILENAME; fflush()
  50         # ignore leading UTF-8 BOM at the start of each input, when present
  51         gsub(/^\xef\xbb\xbf/, "")
  52     }
  53 
  54     # ignore trailing carriage-returns before emitting lines; keep flushing
  55     # output-buffer for each line, in case input lines come in `stutters`,
  56     # as when piping live activity logs, for example
  57     { gsub(/\r$/, ""); print; fflush() }
  58 ' "$@"