Gen 423: Converted shell scripts into nix files

glasshouse-laptop/home/scripts/runbg.nix

@@ -0,0 +1,22 @@
+{ pkgs }:
+
+{
+	runbg = pkgs.writeShellScriptBin "runbg" (''
+#!/usr/bin/env bash
+
+[ $# -eq 0 ] && {  # $# is number of args
+    echo "$(basename $0): missing command" >&2
+    exit 1
+}
+prog="$(which "$1")"  # see below
+[ -z "$prog" ] && {
+    echo "$(basename $0): unknown command: $1" >&2
+    exit 1
+}
+shift  # remove $1, now $prog, from args
+tty -s && exec </dev/null      # if stdin is a terminal, redirect from null
+tty -s <&1 && exec >/dev/null  # if stdout is a terminal, redirect to null
+tty -s <&2 && exec 2>&1        # stderr to stdout (which might not be null)
+"$prog" "$@" &  # $@ is all args
+	'');
+}