1 FDT
 
	FDT is a program designed to assist FORTRAN programmers in
	debugging their programs.    There are two versions of FDT.
	The small FDT is designed to provide the necessary debugging
	tools in a minimum of space.  This version of FDT features:
	 --	Variable examination and modification,
	 --	Execution control (breakpoint set and clear).
	VFDT, is somewhat larger.  It is identical to FDT, but will
	correctly handle virtual arrays. All functions have not yet
	been checked on F77, but it seems to work as well on that
	as on the F4P it was designed for.

	For further information, type 

		AID FDT EXAMPLE		;FOR AN EXAMPLE OF FDT USAGE
		AID FDT COMMANDS	;FOR A LIST OF THE COMMANDS
		or for a full document, you may type
		PRINT DR1:[330,2]FDT.DOC

2 EXAMPLE
	Sample command file for including FDT.

	(Assumes there are three source modules: PROG, SUB1, and SUB2).
 
	F4P PROG,PROG/LI:3=PROG
	F4P SUB1,SUB1/LI:3=SUB1
	F4P SUB2,SUB1/LI:3=SUB2
	TKB @PROG	PROG.CMD file should look like this
			PROG,PROG/-SP/CR=PROG,SUB1,SUB2,LB:[1,1]FDT/DA
			LB:[1,1]F4POTS/LB

	FDT PROG,PROG=PROG,SUB1,SUB2/PROG
 
	(If overlayed, you must not have default core resident library
	F4PRES or SYSRES.  Thus the ODL command file must eliminate this).

	(If virtual arrays must be examined or changed, use LB:[1,1]VFDT).
 
2 COMMANDS
 
	Execution control:
 
	;B				List all breakpoints.
	[module:]entry-name;B		Set breakpoint.
	[module:]statement-number;B
	[module:]@line-number;B
 
	;C				Clear all breakpoints.
	[module:]entry-name;C		Clear a breakpoint.
	[module:]statement-number;C
	[module:]@line-number;C
 
	;G				Return from a breakpoint.
	@line-number;G			Jump to a location and resume
	statement-number;G		execution.
 
	;X				Exit program.
 
	Variable examination:
 
	Variable format:
		[module:]variable-name
 
	Array format (only VFDT can access virtual arrays):
		[module:]array-name[(subscripts)]
 
	Display type terminators:
		/	Display by type.
		;A	Display in ASCII.
		;D	Display in decimal (only affects logical and integer).
		;O	Display in octal (only affects logical and integer).
 
	Modification terminators:
		<carriage-return>	Close location.
		<line-feed>		Open and display next array element.
		   ^			Open and display last array element.

