INT 21 - DOS 1+ - DELETE FILE USING FCBsee File Control Block
	AH = 13h
	DS:DX -> unopened FCBsee File Control Block (see #01345), filename filled with template for
		deletion ('?' wildcards allowed)
Return: AL = status
	    00h one or more files successfully deleted
	    FFh no matching files or all were read-only or locked
Notes:	DOS 1.25+ deletes everything in the current directory (including
	  subdirectories) and sets the first byte of the name to 00h (entry
	  never used) instead of E5h if called on an extended FCBsee File Control Block with
	  filename '???????????' and bits 0-4 of the attribute set (bits 1 and
	  2 for DOS 1.x).  This may have originally been an optimization to
	  minimize directory searching after a mass deletion (DOS 1.25+ stop
	  the directory search upon encountering a never-used entry), but can
	  corrupt the filesystem under DOS 2+ because subdirectories are
	  removed without deleting the files they contain.
	currently-open files should not be deleted
	MS-DOS allows deletion of read-only files with an extended FCBsee File Control Block, whereas
	  Novell NetWare, DR DOS 6, and Novell DOS 7/OpenDOS 7.01 do not
	this function generates a trap "D" under OS/2 v4.x (Warp4) when called
	  on an HPFS partition with a wildcard in the filename; it operates
	  correctly on FATsee File Allocation Table partitions and when called without wildcards
SeeAlso: AH=41h,INT 2F/AX=1113h