Snooze - a more accurate way to bash sleep

snooze

#! /bin/bash

# XCMBuild Snooze Tool
# ..................................
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# see https://github.com/dylanaraps/pure-bash-bible#other
# ideas from https://blog.dhampir.no/content/sleeping-without-a-subprocess-in-bash-and-how-to-sleep-forever
# Their work was based on CC-BY-SA4 from: https://stackoverflow.com/help/licensing
# source: https://unix.stackexchange.com/questions/68236/avoiding-busy-waiting-in-bash-without-the-sleep-command
# code: https://unix.stackexchange.com/a/407383
# author: https://unix.stackexchange.com/users/263036/bolt
# attribute: https://unix.stackexchange.com/questions/68236/avoiding-busy-waiting-in-bash-without-the-sleep-command
# Full License details can be found here: https://creativecommons.org/licenses/by-sa/4.0/
# This implementation is modified and not endorsed

# The following implementation of the `snooze` `BASH` `function` verbatim without its file header and footer,
# is hereby acknowledged to be specifically release under the [CC-BY-SA-4](https://creativecommons.org/licenses/by-sa/4.0/).
function snooze() {
	local IFS
	[[ -n "${_snooze_fd:-}" ]] || { exec {_snooze_fd}<> <(:) && read -r -t 0 -u $_snooze_fd; } 2>/dev/null || {
		# workaround for MacOS and similar systems
		local fifo
		fifo=$(mktemp -u)
		mkfifo -m 700 "$fifo"
		exec {_snooze_fd}<>"$fifo"
		rm "$fifo"
	}
	read -t "${1:-1}" -u $_snooze_fd || :
}
# The immediately proceeding implementation of the `snooze` `BASH` `function` verbatim without its file header and footer,
# is hereby acknowledged to be specifically release under the [CC-BY-SA-4](https://creativecommons.org/licenses/by-sa/4.0/).

export -f snooze