Magtape Copy Program.
	Command format:
	MCP>MM1:=MM0:/switches to copy MM0 to MM1
	or  ? to print this help message
	switches:	/DENS:m (m=800 or 1600) set density
			default = current setting.
			/TM:n stop copying at the nth double tapemark
			(k consecutive tapemarks count as k-1 double)
			default = stop at first double tapemark.
			/-RW do not rewind the tapes
			default = rewind before and after copying.
	If you have only one tape unit, you may use an intermediate file, e.g.
	MCP TEMP=MT0:
	MCP MT0:=TEMP (default extension .TMP)
	NOTE: An ANSI magtape contains a double tapemark for each
	      empty file.