DEBUG

Purpose

Monitor programs during execution

Syntax

DEBUG <program | procedure> [WITH <parameter-list>]

See Also

CANCEL, DISPLAY BREAKPOINT, DISPLAY CALLS, DISPLAY MEMORY, DISPLAY STATUS, DISPLAY WATCHPOINT, DO, LIST BREAKPOINT, LIST CALLS, LIST WATCHPOINT, QUIT, RESUME, SET COMPILE, SET DEVELOPMENT, SET HISTORY, SET STEP, SUSPEND

Description

The DEBUG command displays a pop-up debugger allowing the specified program to be monitored during execution.

The debugger consists of four lines of information about the current program and eighteen push buttons. Program information consists of the following lines:

OPERATION	Displays one of the following DEBUG operations: STEP, BREAKPOINT or WATCHPOINT.
PROGRAM	Displays the name of the current procedure or program.
LINE#	Displays the current line number.
COMMAND	Displays the next program line to be executed.

The eighteen push buttons are used to access information about the current environment and to specify memory variables and conditions to monitor during program execution. The pop-up debugger provides the following push buttons:

BUTTON	EFFECT
Step	Step through a line at a time.
Suspend	Suspend the program to go to the interactive prompt, RESUME to restart.
Cancel	Cancel program execution and create error.mem.
Memory	Display currently declared memory variables.
Status	Display currently open tables (and their indexes, current record, etc.).
Calls	Show program/procedure call stack.
Watch	Set a watch point. When Executing the program, execution will stop when the specified memory variable's value changes.
Break	Set a break point. When Executing the program, execution will stop when the specified condition becomes true.
History	Show command history trace.
Execute	Run program without stepping until watch point or break point reached.
Wpclear	Clear all watch points.
Bpclear	Clear all break points.
Bpmark	Mark the current line as a break point.
Bpdrop	Clear a particular break point.
Wpdrop	Clear a particular watch point.
Bpshow	Show all break points.
Wpshow	Show all watch points.
Quit	Exit the program and debugger.

Use the [UP], [DOWN], [LEFT], and [RIGHT] arrow keys to navigate the push buttons, and press the [RETURN] key to select a button. You may also type the accelerator key to select a button. The accelerator keys are the highlighted letters in the label of each push button.

Debugger directives can also be hard-coded into program files. These are ignored in normal program execution but activated when the program runs in debug mode Debug mode is in effect when the program is called with the DEBUG command or when SET STEP is ON. Directives start with a '//' comment prefix followed by a space, the DEBUG command, a colon (':'), and the condition. The following debugger directives are available:

DIRECTIVE	EFFECT
// DEBUG:BREAKPOINT	Acts as if a break point has been hit when it is encountered.
// DEBUG:BREAKPOINT:<expL>	Acts as if a break point has been hit when <expL> evaluates to .T. (True).
// DEBUG:WATCHPOINT:<memvar>	Sets a watch point on the specified memory variable.

Debugger directives can also be used when programs are run via the Recital Database and Mirage Servers.

Example

debug main

Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer