feat(unitproc/get_rand_line):Bash script that gets random line
[BK-2020-03.git] / unitproc / bkt-read_stdin
1 #!/usr/bin/env bash
2 # Desc: Reads stdin
3
4 yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
5 die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
6 must() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
7 read_stdin() {
8 # Desc: Consumes stdin; outputs as stdout lines
9 # Input: stdin (consumes)
10 # Output: stdout (newline delimited)
11 # Example: printf "foo\nbar\n" | read_stdin
12 # Depends: GNU bash (version 5.1.16)
13 # Version: 0.0.1
14 local input_stdin output;
15
16 # Store stdin
17 if [[ -p /dev/stdin ]]; then
18 input_stdin="$(cat -)";
19 fi;
20
21 # Store as output array elements
22 ## Read in stdin
23 if [[ -n $input_stdin ]]; then
24 while read -r line; do
25 output+=("$line");
26 done < <(printf "%s\n" "$input_stdin");
27 fi;
28
29 # Print to stdout
30 printf "%s\n" "${output[@]}";
31 }; # read stdin to stdout lines
32 main() {
33 read_stdin "$@";
34 };
35
36 main "$@";