feat(user/bkfeh):Process stdin and psargs separately

[BK-2020-03.git] / unitproc / bkt-read_stdin

diff --git a/unitproc/bkt-read_stdin b/unitproc/bkt-read_stdin
new file mode 100644 (file)
index 0000000..31469b3
--- /dev/null
+++ b/unitproc/bkt-read_stdin
@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+# Desc: Reads stdin
+
+yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
+die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
+must() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
+read_stdin() {
+    # Desc: Consumes stdin; outputs as stdout lines
+    # Input: stdin (consumes)
+    # Output: stdout (newline delimited)
+    # Example: printf "foo\nbar\n" | read_stdin
+    # Depends: GNU bash (version 5.1.16)
+    # Version: 0.0.1
+    local input_stdin output;
+
+    # Store stdin
+    if [[ -p /dev/stdin ]]; then
+        input_stdin="$(cat -)";
+    fi; 
+    
+    # Store as output array elements
+    ## Read in stdin
+    if [[ -n $input_stdin ]]; then
+        while read -r line; do
+            output+=("$line");
+        done < <(printf "%s\n" "$input_stdin");
+    fi;
+
+    # Print to stdout
+    printf "%s\n" "${output[@]}";
+}; # read stdin to stdout lines
+main() {
+    read_stdin "$@";
+};
+
+main "$@";