This section describes basic operational requirements and provides a rough guideline on how to proceed when planning to apply the debugger.
The use of the debugger can be controlled by Natural Security:
You can protect the debugger against unauthorized use by disallowing the TEST
system command, which invokes the debugger; see Command Restrictions in the section Library Maintenance in the Natural Security documentation.
You can disallow or restrict the use of the debugger as described in Components of an Environment Profile in the Natural Security documentation.
The debugger is only invoked when you execute a cataloged object stored
in the current library in the current Natural system file. The debugger is
not invoked when you execute source code contained in the work area by
using the RUN
command.
Efficient and correct debugging requires that the source code in the
source object corresponds to the compiled source code in the cataloged object
which can be guaranteed with the system command
STOW
. If you change a source object after
you cataloged it, it is possible that a debug entry (breakpoint or watchpoint)
does not function properly because the referenced statement or variable has
changed or no longer exists. When the debugger detects that a source object has
an earlier time stamp than the corresponding cataloged object, the following
warning appears Time stamps of source and cataloged object do not
match.
The debugger investigates all Natural objects contained in the current library or in one of its steplibs. The debugger does not investigate Natural objects stored in the Natural system library SYSLIB or SYSLIBS.
The following restrictions apply to the use of the debugger:
The debugger can only be applied to objects of Natural Version 2.3 and above, but not to Natural objects cataloged with any previous version. The debugger supports only debug environments which were created with Natural Version 2.3 and above; debug environments created with any previous version will be ignored. For detailed information on debug environments, see Debug Environment Maintenance.
For objects cataloged in Natural versions earlier than Version 4.1, breakpoints can only be set on lines with WHEN
and VALUE
clauses. These restrictions do not apply to objects cataloged in Natural Version 4.1 and above.
Although the debugger is mainly designed for interactive usage in online mode, the debugger commands can also be used for batch execution such as for setting breakpoints or watchpoints.
Note:
There are restrictions for batch processing which can cause a
debugger command to be rejected. For example, the debugger does not support the
commands ++
and
+4
.
The following is an example of using debugger direct commands in batch mode to generate and print a report about call statistics:
//NATBATCH EXEC PGM=NATBAT42, // PARM=('INTENS=1,IM=D,CF=$,PRINT=((1-2),AM=STD)') //STEPLIB DD DISP=SHR,DSN=NATURAL.V2.TEST.NUCLEUS //CMPRINT DD SYSOUT=X //SYSOUT DD SYSOUT=X //CMPRT01 DD SYSOUT=X //CMSYNIN DD * LOGON DEBUGLIB TEST PROFILE ,,,,CMPRT01 ,,,,,,$K3 ,,$K3 TEST ON TEST SET XSTAT COUNT DEBUG2P TEST PRINT XSTAT FIN /*
To invoke the debugger
Establish a debug environment for a Natural object or application:
Invoke the Debug Main Menu by entering the
Natural system command TEST
.
Or:
From within a running application, enter the terminal
command %<TEST
.
Use the functions of the Debug Main Menu to specify debug entries for a Natural object or application:
Debug environment maintenance
Spy maintenance
Breakpoint maintenance
Watchpoint maintenance
Call statistics maintenance
Statement execution statistics maintenance
Variable maintenance
List object source
Activate the debugger:
At a command prompt, enter the command TEST
ON
.
Or:
In the Debug Main Menu, enter
function code T
.
Execute the Natural object or application.
The debugger pauses program execution at the specified debug entries and invokes the Debug Break window.
To invoke the debugger for error handling
At session start, set the profile parameter
DBGERR
to ON
.
See also DBGERR - Automatic Start of Debugger at Runtime Error in the Parameter Reference documentation.
Or:
During the session, enter the command TEST
ON
at a command prompt or enter function code T
in a
main debug maintenance menu.
The debugger invokes the Debug Break window when a Natural error occurs.
See also the section Error Handling.
The maintenance functions of the debugger as described in the relevant
sections, refer to objects you specify either in the corresponding name fields
of menus or with direct commands. If you do not specify an object name, by
default, the debugger assumes the name of the current object as it is displayed
in the Object field, in the upper right corner of the
Debug Main Menu. With a default object specified, no
object name is required in direct commands and menu options used to specify
breakpoints or watchpoints. To change the default object, see the syntax of the
command SET
in
the section Command Summary and Syntax.