unitproc/bkt-read_stdin_psarg

   1 #!/usr/bin/env bash
   2
   3 yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
   4 die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
   5 must() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
   6 read_stdin_psarg() {
   7     # Desc: Consumes stdin and reads arguments; outputs as stdout lines
   8     # Input: stdin (consumes)
   9     # Input: args
  10     # Output: stdout (newline delimited)
  11     # Example: read_stdin_psarg "$@"
  12     # Depends: GNU bash (version 5.1.16)
  13     local input_stdin input_psarg output;
  14
  15     # Store stdin
  16     if [[ -p /dev/stdin ]]; then
  17         input_stdin="$(cat -)";
  18     fi;
  19     yell "DEBUG:$(declare -p input_stdin)";
  20
  21     # Store arguments
  22     if [[ $# -gt 0 ]]; then
  23         input_psarg="$@";
  24     fi;
  25     yell "DEBUG:$(declare -p input_psarg)";
  26
  27     # Combine as output array elements
  28     ## Read in stdin
  29     if [[ -n $input_stdin ]]; then
  30         while read -r line; do
  31             output+=("$line");
  32         done < <(printf "%s\n" "$input_stdin");
  33     fi;
  34     ## Read in positional arguments
  35     if [[ -n $input_psarg ]]; then
  36         for arg in "$@"; do
  37             output+=("$arg");
  38         done;
  39     fi;
  40     yell "DEBUG:$(declare -p output)";
  41
  42     # Print to stdout
  43     printf "%s\n" "${output[@]}";
  44 }; # read stdin and positional argument to stdout lines
  45
  46 main() {
  47     read_stdin_psarg "$@";
  48 };
  49
  50 main "$@";