MXGDB(1) X Version 11/OSF Motif MXGDB(1)
Jan 10 1992
NAME
mxgdb - Motif based X window system interface to the gdb debugger.
SYNOPSIS
mxgdb [ -toolkitoption ... ] [-mxgdboption ... ] [-gdboption ... ]
[objfile [ corefile ]]
DESCRIPTION
Mxgdb is a Motif based graphical user interface to the gdb debugger
under the X Window System. It provides visual feedback and mouse
input for the user to control program execution through breakpoints,
to examine and traverse the function call stack, to display values of
variables and data structures, to browse source files and functions
and to obtain help on gdb commands and options. Mxgdb allows initial
gdb commands stored in the file .gdbinit to be executed immediately
after the symbolic information is read. If .gdbinit does not exist in
the current directory, the user's home directory is searched
(~/.gdbinit). Objfile is an object file produced by a compiler with
the appropriate option (-g) specified to produce symbol table
information for gdb. If no objfile is specified, the file command can
be used later to specify the program to be debugged. If a file named
core exists in the current directory or a corefile is specified, mxgdb
can be used to examine the state of the program when the core dump
occurred. The name of the debugger invoked by mxgdb is, by default,
gdb, but it can be overridden with the environment variable
MXGDB_DEBUGGER. Likewise the prompt used by gdb can be overriden by
the environment variable GDB_PROMPT.
OPTIONS
Mxgdb accepts all of the standard X Toolkit command line options (see
X(1)), and all the gdb options (see gdb(1)), plus the following mxgdb
specific options:
-bigicon
Uses a 64x64 icon instead of the default 48x48 icon.
-cmdd
Uses a separate detached window to hold command buttons instead
of the default button layout in the Source Window.
WINDOW PANES
The mxgdb interface consists of the following window panes:
Menu Pane Provide access to the File, Commands and Help
pulldown menus.
File Window Display the full pathname of the file displayed in
the source window, and the line number of the
caret.
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Source Window Display the contents of a source file and provides
a set of buttons of the common gdb commands which
are invoked by pressing the LEFT mouse button
down. Browsing text in the window is possible via
the cursor keys, pg up/down, and the vertical
scroll bar (see SCROLLBAR). viewing lines greater
than the window's width is possible through the
left page and right page command buttons.
Message Window Display the execution status and error messages of
mxgdb.
Dialogue Window Provide a typing interface to gdb which is
identical to the gdb command line interface with
the exception that mxgdb reserves the right to
intercept output for its own interpretation and
use. The relative sizes of the Source Window and
the Dialogue Window can be adjusted by dragging
the grip (a small square near the right edge of a
horizontal border) with the LEFT mouse button
down. Ordering of the command buttons in the
Source Window will not change when the window is
resized but the height of the buttons will change
to completely fill the height of the window.
DIALOG WINDOWS
Mxgdb can optionally display the following dialog windows:
Display Window Provide a window with a scrolling work area for
displaying variables each time execution stops.
Help Window Provide a window for access to gdb's built in help
functions. The basic components of this window are
a scrolling work area and a command line. The work
area contains gdb's help text menu where the
commands and categories are placed in buttons.
Selecting these buttons accesses help more
specific to the respective command or category.
The command line always contains a Quit button,
which will remove the Help Window if chosen, and
optionally an Up Arrow button which only appears
if you have chosen an additional help selection
from the work area. In this case choosing the Up
Arrow button will return you to the previous help
text menu.
File Selection Window
Provide a window for selection of directories,
executables and source files. The File Selection
Window consists of five basic components: a
Filter, which can be edited and which affects what
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Jan 10 1992
appears in the Directories list and the Files
list, a Selection which can either be edited or
altered by selecting elements of the Directories
or Files lists, and a set of Buttons which control
the use of the Selection contents. The File
Window initially starts by displaying the current
directory and its contents. You can use the Filer
button to change the displayed directory or to
restrict the set of files which are displayed in
the Files list. Selecting the OK button will
provide a listing of the file if it is one fo the
current source files, will use it as the exec-file
and symbol-file if it is executable or will add it
to the source path if it is a directory.
Selecting the Cancel button will remove the File
Selection Window without executing any commands.
Search Window Provide a window for searching through the
contents of the Source Window. This window has
five components: a Selection which is edited for
the string to search for, a Down button which
scans the Source Window for occurrences of the
Selection down from the current line, an Up button
which scans the Source Window for occurrences of
the Selection up from the current line, a Cancel
button which ends the search and returns the text
to the original line, and a Stop button which ends
the search but stays at the current line.
Commands Window Provide a window to contain the command buttons
(appears only if mxgdb was invoked with -cmdd or
if the useCommandDialog resource is set to True).
Xtty Window Provide a pseudo-tty device through an xterm for
use by the debug process for character I/O. This
pdeudo-device uses the xterm terminal type and is
configured with the following terminal settings:
intr = DEL; quit = ^|; erase = ^h; kill = ^u; eof
= ^d; eol = ^` swtch = ^z; susp = ^z -parenb
-parodd cs8 -cstopb hupcl cread -clocal -loblk
-ignbrk brkint ignpar -parmrk -inpck -istrip
-inlcr -igncr icrnl -iuclc -ixon -ixany -ixoff
isig icanon -xcase echo echoe echok echonl -noflsh
-tostop -iexten opost -olcuc onlcr -ocrnl -onocr
-onlret -ofill -ofdel
Exit Window Asks the user if he really wishes to exit mxgdb.
Selecting OK will exit mxgdb immediately.
Selecting Cancel will remove the window and return
to mxgdb.
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Jan 10 1992
Info Window Provides a window containing the authors' names,
the current versions and date and any additional
information on this version.
PULL DOWN MENUS
The following pull menus are provided with mxgdb:
File
File... Invoke the File Selection Window dialog.
Search... Invoke the Search Window dialog.
Commands... Redisplay the Commands Window dialog (this is only
sensitive if the Commands Window is being used).
Xtty... Invoke the Xtty Window and direct gdb to use it
(via gdb's stty function). Selecting Xtty a second
time will remove the Xtty Window and reset gdb to
use the normal I/O terminal.
Exit... Presents the Exit Window and asks if you wish to
exit mxgdb.
Commands The entries in the Commands menu contains the
following groups of gdb commands:
Running run continue next step finish
Data print display undisplay
Breakpoints break clear tbreak
Stack up down
Info locals args stack
Help
Gdb Help... Invokes the Help Window dialog.
Info... Invokes the Info Window dialog.
KEY BINDINGS AND ACCELLERATORS
Mxgdb uses the following key bindings in the respective windows:
Source Window (add later)
Dialog Window (add later) Mxgdb defines the following
accellerator keys:
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Jan 10 1992
Cntrl-f Invokes the File Selection Window.
Cntrl-x Invokes the Exit Window.
Cntrl-w Invokes the Search Window.
Cntrl-r Executes the run command.
Cntrl-n Executes the next command.
Cntrl-s Executes the step command.
Cntrl-p Executes the print command.
Cntrl-b Executes the break command.
Cntrl-g Executes the up command.
Cntrl-j Executes the down command.
Cntrl-h Invokes the Help Window.
SELECTION
Text selection in the source window is modified to make it easier to
select C expressions. Using the LEFT mouse button in combination with
the SHIFT key selects a C expression by highlighting it in reverse-
video. LEFT mouse button down alone positions the caret and updates
the line label accordingly. C expression selection is based on the
resource delimiters which determines the set of characters that
delimits a C expression. Text selection adjustment is possible by
holding the LEFT mouse button down and dragging. To paste a selection
in the Dialog Window press the MIDDLE mouse button down. The selection
will be put on the mxgdb command line only and cannot be inserted
anywhere but the command line. A selection may be inserted from any
text selection available on the given display. Selection of displayed
varables in the Display Window is also made easier. Using the LEFT
mouse button down on the line containing the variable name the
displayed variable is automatically selected by its number (see the
description of the undisplay command button).
SCROLLBAR
Pressing the LEFT mouse button scrolls the text forward, whereas
pressing the RIGHT mouse button scrolls the text backward. The amount
of scrolling depends on the distance of the pointer button away from
the top of the scrollbar. If the button is pressed at the top of the
scrollbar, only one line of text is scrolled. If the button is
pressed at the bottom of the scrollbar, one screenful of text is
scrolled. Pressing the MIDDLE mouse button changes the thumb position
of the scrollbar. Dragging the MIDDLE mouse button down moves the
thumb along and changes the text displayed.
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COMMAND BUTTONS
The mxgdb command buttons are positioned either in the left margin of
the Source Window (by default) or in the Command Window dialog. The
buttons are situated vertically in two columns and correspond (from
top to bottom). The following commands can be chosen by pressing the
LEFT mouse button down within the command button:
run Begin program execution.
stack Show a stack trace of the functions called.
locals Print the local variables of the selected frame, each on a
separate line. These are all variables declared static or
automatic within all program blocks that execution in this
frame is currently inside of.
up Move up one level on the call stack.
args Print the arguments of the selected stack frame, each on a
separate line.
down Move down one level on the call stack.
print * Print the value of the object the selected expression is
pointing to.
print Print the value of a selected expression.
cont Continue execution from where it stopped.
step Execute one source line, stepping into a function if the
source line contains a function call.
finish Continue execution until the selected procedure returns; the
current procedure is used if none is selected.
next Execute one source line, without stepping into any function
call.
clear Remove the breakpoint on the source line selected or the
function name selected.
break Stop program execution at the line selected. To set a
breakpoint in the program, place the caret on the source
line and choose the break button. A stop-sign will appear
next to the source line. To set a breakpoint in a function,
select the function name and choose the break button. A
stop-sign will be placed near the first executable line of
the function.
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Jan 10 1992
undisplay Stop displaying the value of the selected expression in the
Display Window dialog. If the selected expression is a
constant, it refers to the display number associated with an
expression in the display window.
display Display the value of a selected expression in the Display
Window dialog, updating its value every time execution
stops.
left page Shift the Source Window contents to the left so that lines
longer that the width of the Source Window can be made
visible.
right page
Shift the Source Window contents to the right.
X DEFAULTS
To change the default values of widget resources used in mxgdb, you
need to reference the widgets by name or by class. The widget
hierarchies for the window panes and the dialog windows are given in
the file /usr/lib/X11/app-defaults/Mxgdb. These can overriden by
making similar entries in the .Xdefaults file in you home directory.
In addition to the standard X resources, mxgdb uses the following
application-specific resources for user customization. The value in
parentheses is the default value.
bell If True, the bell is on. (True)
displayWindow
If True, the display window appears on start up. (False)
delimiters
The set of delimiters for word selection. (" !%^&*()+=~|;:{},/#<?
prompt
The prompt string used in mxgdb. ("(mxgdb) ")
button_color
Color of all of the buttons not specified below. (Black)
stop_color
Color of the stop sign, and set/clear breakpoint buttons. (Red)
arrow_color
Color of the arrow sign, and the right/left scroll buttons.
(Blue)
updown_color
Color of the updown sign, and the up/down stack buttons. (Blue)
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Jan 10 1992
bomb_color
Color of the bomb sign. (Red)
FILES
a.out default object file
core default core file
.gdbinit local initial commands file
~/.gdbinit user's initial commands file
SEE ALSO
X(1), gdb(1)
LIMITATIONS
BUGS
Output from the debug program can fool the mxgdb parser if an Xtty
Window is not used to manage I/O from the debug process. A separate
asynchronous pseudo-tty should be used as the default means of I/O
with the debug process.
COPYRIGHT
Derived from manpage from xxgdb(1) Derived from manpage from xdbx(1)
Copyright 1989 The University of Texas at Austin Copyright 1990
Microelectronics and Computer Technology Corporation Copyright 1991
Bull HN
AUTHOR
Po Cheung (xdbx(1)) Jim Tsillas (mxgdb(1))
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