PROGRAM
	copy - copy characters from standard input to standard output
USAGE
	copy
DESCRIPTION
	copy copies its input to its output unchanged. It is useful for copying from
	a text terminal to a file, from a file to a file, from a text terminal to a
	text terminal, or from a file to a text terminal (to display it).

	This program is also from the Pascal User Manual and Report, Second Edition,
	by Kathleen Jensen and Niklaus Emil Wirth, pg. 164.

	On Unix (e.g. macOS, OpenBSD) and GNU/Linux, use the cat command to do the
	same.
EXAMPLE
	C:\Users\David> copy
	hello, world
	hello, world
	^Z

	C:\Users\David> echo "hello, world" > hello.txt
	C:\Users\David> copy <hello.txt
	hello, world