wguidrwc.gml

开放源码的编译器open watcom 1.6.0版的源代码

stack frames currently on the stack is called a call chain.
.np
.ix 'call chain'
The stack trace function lets you walk the call chain. This allows you
to determine where each function in the call chain was called from and
where it will return to. To perform a stack trace, click on the Stack
Trace button in the Task Status dialog to reveal the Stack Trace
dialog.
.keep 16
.figure *depth='2.34' *scale=63 *file='DRW11' The Stack Trace dialog allows you to walk the call chain.
.np
When the Stack Trace dialog opens, it contains information from the
stack frame for the function that was executing at the time of the
fault. The Instructions Around Fault section displays the assembly
instructions around the call to the faulting function. The instruction
directly after the call to the faulting function is marked with an
asterisk. Other information includes the address of this instruction
(CS:IP) and the base stack pointer (SS:BP) at the time of the call. If
the faulting module contained debugging information and the marked
assembly instruction corresponds to a source line, then source file
information appears.
.np
Selecting the Next button displays information from the next oldest
stack frame. This is information about the point from which the
currently displayed function was called. If the currently displayed
function was called by the operating system, then the message "No more
stack frames!" appears because there are no stack frames for calls
made from the operating system.
.np
Selecting the Prev button displays information from the next most
recent stack frame. This moves you in the opposite direction along the
call chain as pressing the Next button.
.np
The Cancel button closes the window.
.*
.endlevel
.*
.section Resetting the Fault Handled Flag
.*
.ix 'Fault Handled Flag'
.ix '&drwc' 'Fault Handled Flag'
.np
The Reset Fault Handled Flag menu item is only accessible when an
exception occurs from which &drwc is unable to recover. When such an
error occurs, &drwc cannot log exceptions or be terminated until you
choose Reset Fault Handled Flag from the File menu. This will not
happen frequently.
.*
.endlevel
.*
.section &drwc.: Working with Log Files
.*
.ix '&drwc' 'Log files'
.ix 'Log files'
.np
A log file is a text file created by &drwc.. The log file consists of
entries that describe the state of the system at the time the entry
was made. &drwc gives you the opportunity to create a log file entry
each time an exception occurs. Such entries include information about
the state of the program that caused the exception, as well as
information about the state of the system. You can create a log file
entry at any time using the Log Current State menu item in the Log
menu.
.np
A log file is a permanent record of the state of the system and,
possibly, your program. With a log file you can make note of an error
and return to it at a later time to examine and debug the problem.
.*
.beglevel
.*
.section Log the Current State
.*
.ix 'Log Current State'
.ix '&drwc' 'Log Current State'
.np
Choose Log Current State from the Log menu to write to the current log
file. This tells &drwc to create a log file entry with all of the log
details except the Offending Task Information. The settings in the Log
Options dialog determine the information written to the log file.
.np
The Log Current State item is also available on the system menu.
.*
.section Erase the Log File
.*
.ix 'Erase Log File'
.ix '&drwc' 'erase log file'
.ix 'Log File' 'erase'
.np
To erase the current log file, choose Erase Log File from the Log
menu. This erases the log file specified in the Log File Options
dialog.
.np
Choosing this item reveals a message box which asks you to verify that
you want to erase the specified log file. Select yes to erase the log
file or No to cancel the request.
.*
.section *refid=drwccu Customize the Log File
.*
.ix 'Log File' 'customizing'
.ix '&drwc' 'customize log file'
.np
The Log Options item in the Log menu opens the Log Options
dialog where you indicate to &drwc the information you want to appear
in log file entries. The Log Options item is also available from the
system menu.
.keep 23
.figure *depth='3.73' *scale=64 *file='DRW12' In the Log Options dialog, you customize the log file to which you write information.
.np
The following sections describe the options that make up the Log
Options dialog.
.*
.beglevel
.*
.section &drwc.: Naming the Log File
.*
.np
.ix 'Log File' 'naming'
.ix '&drwc' 'naming the log file'
In the Log File Name field you can specify the file to which &drwc
writes the log file entries. The Browse button to the right of this
field opens the Pick Log Filename dialog. This dialog lets you browse
your file structure and select the path to which &drwc writes the log
file entries.
.*
.section &drwc.: Specifying the Log File Data
.*
.ix 'Log file' 'data'
.ix '&drwc' 'specify log file data'
.np
In the Log File Data and Disassembly Options sections of the Log File
Options dialog you select the information you want to appear in the
log file. The Log File Data section lists the various types of
information that can be included in a log file. If the check box for a
piece of information is marked then that type of information will be
written to the log file. The options in this section are:
.begpoint $break Log File Data
.point Stack Trace
When this option is selected stack trace information for the
application that caused the exception is written when a log file entry
is made. This option only affects log entries made due to exceptions.
.point Current Tasks
When this option is selected a list of all tasks currently running in
the system, including information about each task is included in each
log entry.
.point All Modules
When this option is selected a list of all modules currently loaded in
the system, including information about each module is included in each
log entry.
.point GDI Heap Info
When this option is selected summary information about the state of the
GDI local heap is included in each log entry.
.point User Heap Info
When this option is selected summary information about the state of the
User local heap is included in each log entry.
.point Mem Manager Info
When this option is selected summary information about the state of
the virtual memory manager is included in each log entry.
.point Module Segments
When this option is selected log file entries list the selectors
for each module currently loaded in the system. The All Modules
option must also be selected to write this information.
.point Query for Notes
When the Query for Notes option is selected &drwc displays an
Annotate Log dialog whenever a log file entry is made. This dialog
lets you enter some explanatory text that will be included in
the log file entry.
.keep 19
.figure *depth='3.00' *scale=100 *file='DRW13' In the Annotate Log dialog box, enter text you want to include in the log file entry.
.np
Enter any text you want to include in the space provided. Press the OK
button to include this text in the log file. If you press the Cancel
button &drwc continues to create the log file entry but does not
include any information from the dialog.
.endpoint
.np
The values in the Disassembly Options box only affect log entries made
due to exceptions. These values relate to the disassembly section
appearing in the log file. The value in the Disasm Backup field tells
&drwc the number of instructions before the fault you want written to
the log file. The value in the Disasm Lines field tells &drwc the
total number instructions you want it to show in the log file. This
value includes the instructions displayed before the fault.
.*
.section &drwc.: Other Options
.*
.ix 'Auto Log'
.ix '&drwc' 'Auto Log'
.ix '&drwc' 'Log Restarted Tasks'
.ix 'Log Restarted Tasks'
.np
If the Auto Log option is selected, &drwc creates a log file when an
exception occurs and then terminates the application that caused the
fault instead of revealing the exception dialog. The Auto Log option is
useful when running test streams.
.np
The Max Log File Size field allows you to set the maximum size in bytes
for a log file. When the log file exceeds this size, &drwc prompts you
with a message box when you start the application.
.keep 14
.figure *depth='2.02' *scale=100 *file='DRW14' A message box prompts you to erase the log file when it becomes larger than the maximum log file size specified on the Log File Options dialog.
.np
This message box offers you the opportunity to delete your log file
before it becomes uncontrollably large.
.*
.endlevel
.*
.endlevel
.*
.section Performing Task Control
.*
.ix 'Task Control'
.ix '&drwc' 'task control'
.np
Choosing Task Control from the Task menu or the System menu opens the
Task Control dialog. This dialog displays a Task List which consists
of all programs currently running under Windows. The Task Control
dialog lets you terminate and debug tasks.
.np
The task list in the Task Control dialog is different from the
system Task List which appears when you double click on the wallpaper.
The system Task List list displays only applications that currently
have a window open on the desktop. The task list in the Task Control
dialog lists all tasks regardless of whether they have a window open.
.*
.beglevel
.*
.section Terminating a Task
.*
.ix 'Kill Task'
.ix '&drwc' 'Kill Task'
.ix 'Task Control'
.np
The Kill Task button on the Task Control dialog terminates a task
listed in the Task List. This function is extremely powerful. It
allows you to terminate programs immediately without giving them the
opportunity to clean up by saving data, unloading DLLs, and freeing
allocated memory.
.np
For this reason, you should exercise care when using this function. It
is wise to only use the Kill Task function for tasks that cannot be
terminated in the usual way.
.begstep To terminate a task:
.step Choose Task Control
from the Task menu.
.result
This opens the Task Control dialog containing a list of all tasks
currently running in the system.
.keep 19
.figure *depth='2.96' *scale=80 *file='DRW15' In the Task Control dialog, you can terminate a task selected from the Task List.
.step Select the task you want to terminate
by clicking on its entry in the task list.
.step Select the Kill Task button.
.result
This terminates the selected task, removing it from the task list.
&drwc enters this event in the event list.
.endstep
.*
.section Debugging a Task
.*
.ix 'Task' 'debugging'
.ix '&drwc' 'debugging a task'
.ix 'Debugging' 'tasks in &drwc'
.np
Use the Debug Task button on the Task Control dialog to attach the
debugger to the selected task from the Task List.
.begstep To debug a task:
.step Choose Task Control from the Task menu.
.result
This opens the Task Control dialog containing a list of all tasks
currently running in the system.
.step Select the task you want to debug
by clicking on its entry in the task list.
.step Select the Debug Task button.
.result
This opens the Debugger Options dialog box.
.keep 17
.figure *depth='2.56' *scale=100 *file='DRW16' In the Debugger Option dialog, you enter the command line options to pass to the debugger.
.step Enter the command line options
you want &drwc to pass to the debugger.
.step Click on OK.
.result
This starts the debugger.
.endstep
.*
.endlevel