 |
HP OpenVMS Debugger Manual
The debugger might do type conversion during a deposit operation if the
language rules allow it. For example, a real value specified to the
right of the equal sign might be converted to an integer value if it is
being deposited into a location with an integer type. In general, the
debugger tries to follow the assignment rules for the current language.
There are several ways of changing the type associated with a program
location so that you can deposit data of a different type into that
location:
- To change the default type for all locations that do not
have a symbolic name, you can specify a new type with the SET TYPE
command.
- To change the default type for all locations (both those
that do and do not have a symbolic name), you can specify a new type
with the SET TYPE/OVERRIDE command.
- To override the type currently associated with a particular
location for the duration of a single DEPOSIT command, you can specify
a new type by using a qualifier (/ASCII:n, /BYTE,
/TYPE=(name), and so on).
When debugging a C program, or a program in any case-specific language,
you cannot use the DEPOSIT/TYPE command if the type specified is a
mixed or lowercase name. For example, suppose the program has a
function like the following:
xyzzy_type foo ()
{
xyzzy_type z;
z = get_z ();
return (z);
}
|
If you try to enter the following command, the debugger issues a
message that it cannot find the type "xyzzy_type":
DBG> DEPOSIT/TYPE=(xyzzy_type) z="whatever"
|
The debugger can interpret and display integer data in any one of four
radixes: binary, decimal, hexadecimal, and octal.
The default radix for both data entry and display is decimal for most
languages. The exceptions are BLISS and MACRO, which have a default
radix of hexadecimal.
You can use the SET RADIX and SET RADIX/OVERRIDE commands to change the
default radix.
The DEPOSIT command sets the current entity built-in symbols %CURLOC
and period (.) to the location denoted by the address expression
specified. Logical predecessors (%PREVLOC or the circumflex character
(^)) and successors (%NEXTLOC) are based on the value of the current
entity.
Related commands:
CANCEL TYPE/OVERRIDE
EVALUATE
EXAMINE
MONITOR
(SET,SHOW,CANCEL) RADIX
(SET,SHOW) TYPE
Examples
This command deposits the value 7 into the integer variable I.
| #2 |
DBG> DEPOSIT WIDTH = CURRENT_WIDTH + 24.80
|
This command deposits the value of the expression CURRENT_WIDTH + 24.80
into the real variable WIDTH.
| #3 |
DBG> DEPOSIT STATUS = FALSE
|
This command deposits the value FALSE into the Boolean variable STATUS.
| #4 |
DBG> DEPOSIT PART_NUMBER = "WG-7619.3-84"
|
This command deposits the string WG-7619.3-84 into the string variable
PART_NUMBER.
| #5 |
DBG> DEPOSIT EMPLOYEE.ZIPCODE = 02172
|
This command deposits the value 02172 into component ZIPCODE of record
EMPLOYEE.
| #6 |
DBG> DEPOSIT ARR(8) = 35
DBG> DEPOSIT ^ = 14
|
In this example, the first DEPOSIT command deposits the value 35 into
element 8 of array ARR. As a result, element 8 becomes the current
entity. The second command deposits the value 14 into the logical
predecessor of element 8, namely element 7.
| #7 |
DBG> FOR I = 1 TO 4 DO (DEPOSIT ARR(I) = 0)
|
This command deposits the value 0 into elements 1 to 4 of array ARR.
| #8 |
DBG> DEPOSIT COLOR = 3
%DEBUG-E-OPTNOTALLOW, operator "DEPOSIT" not allowed on
given data type
|
The debugger alerts you when you try to deposit data of the wrong type
into a variable (in this case, if you try to deposit an integer value
into an enumerated type variable). The E (error) message severity
indicates that the debugger does not make the assignment.
| #9 |
DBG> DEPOSIT VOLUME = - 100
%DEBUG-I-IVALOUTBNDS, value assigned is out of bounds
at or near '-'
|
The debugger alerts you when you try to deposit an out-of-bounds value
into a variable (in this case a negative value). The I (informational)
message severity indicates that the debugger does make the assignment.
| #10 |
DBG> DEPOSIT/BYTE WORK = %HEX 21
|
This command deposits the expression %HEX 21 into location WORK and
converts it to a byte integer.
| #11 |
DBG> DEPOSIT/OCTAWORD BIGINT = 111222333444555
|
This command deposits the expression 111222333444555 into location
BIGINT and converts it to an octaword integer.
| #12 |
DBG> DEPOSIT/FLOAT BIGFLT = 1.11949*10**35
|
This command converts 1.11949*10**35 to an F_floating type value and
deposits it into location BIGFLT.
| #13 |
DBG> DEPOSIT/ASCII:10 WORK+20 = 'abcdefghij'
|
This command deposits the string "abcdefghij" into the
location that is 20 bytes beyond that denoted by the symbol WORK.
| #14 |
DBG> DEPOSIT/INSTR SUB2+2 = 'MOVL #20A,R0'
|
On VAX systems, this command deposits the instruction MOVL #20A,R0'
into the location SUB2 + 2 bytes.
| #15 |
DBG> DEPOSIT/TASK VAR = %TASK 2
DBG> EXAMINE/HEX VAR
SAMPLE.VAR: 0016A040
DBG> EXAMINE/TASK VAR
SAMPLE.VAR: %TASK 2
DBG>
|
The DEPOSIT command deposits the Ada task value %TASK 2 into location
VAR. The subsequent EXAMINE commands display the contents of VAR in
hexadecimal format and as a task value, respectively.
DISABLE AST
Disables the delivery of asynchronous system traps (ASTs) in your
program.
Format
DISABLE AST
Description
The DISABLE AST command disables the delivery of ASTs in your program
and thereby prevents interrupts from occurring while the program is
running. If ASTs are delivered while the debugger is running
(processing commands, and so on), they are queued and are delivered
when control is returned to the program.
The ENABLE AST command reenables the delivery of ASTs, including any
pending ASTs (ASTs waiting to be delivered).
Note
Any call by your program to the $SETAST system service that enables
ASTs overrides a previous DISABLE AST command.
|
Related commands:
(ENABLE,SHOW) AST
Example
|
DBG> DISABLE AST
DBG> SHOW AST
ASTs are disabled
DBG>
|
The DISABLE AST command disables the delivery of ASTs in your program,
as confirmed by the SHOW AST command.
DISCONNECT
Releases a process from debugger control without terminating the
process (kept debugger only).
Format
DISCONNECT process-spec
Parameters
process-spec
Specifies a process currently under debugger control. Use any of the
following forms:
|
[%PROCESS_NAME]
process-name
|
The process name, if that name does not contain spaces or lowercase
characters. The process name can include the asterisk (*) wildcard
character.
|
|
[%PROCESS_NAME] "
process-name "
|
The process name, if that name contains spaces or lowercase characters.
You can also use apostrophes (') instead of quotation marks (").
|
|
%PROCESS_PID
process_id
|
The process identifier (PID, a hexadecimal number).
|
[%PROCESS_NUMBER]
process-number
(or %PROC
process-number)
|
The number assigned to a process when it comes under debugger control.
A new number is assigned sequentially, starting with 1, to each
process. If a process is terminated with the EXIT or QUIT command, the
number can be assigned again during the debugging session. Process
numbers appear in a SHOW PROCESS display. Processes are ordered in a
circular list so they can be indexed with the built-in symbols
%PREVIOUS_PROCESS and %NEXT_PROCESS.
|
|
process-set-name
|
A symbol defined with the DEFINE/PROCESS_SET command to represent a
group of processes.
|
|
%NEXT_PROCESS
|
The next process after the visible process in the debugger's circular
process list.
|
|
%PREVIOUS_PROCESS
|
The process previous to the visible process in the debugger's circular
process list.
|
|
%VISIBLE_PROCESS
|
The process whose stack, register set, and images are the current
context for looking up symbols, register values, routine calls,
breakpoints, and so on.
|
Description
(Kept debugger only.) The DISCONNECT command releases a specified
process from debugger control without terminating the process. This is
useful if, for example, you have brought a running program under
debugger control with a CONNECT command and you now want to release it
without terminating the image. (In contrast, when you specify a process
with the EXIT or QUIT command, the process is terminated.)
Caution
The debugger kernel runs in the same process as the image being
debugged. If you issue the DISCONNECT command for this process, you
release your process, but the kernel remains activated.
This activation continues until the program image finishes running.
If you install a new version of the debugger while one or more
disconnected but activated kernels inhabit user program space, you can
experience problems with debugger behavior if you try to reconnect to
one of those kernels.
|
Related commands:
EXIT
QUIT
CONNECT
Example
This command releases process JONES from debugger control without
terminating the process.
DISPLAY
Creates a new screen display or modifies an existing display.
Note
This command is not available in the HP DECwindows Motif for OpenVMS user interface to
the debugger.
|
Format
DISPLAY display-name [AT window-spec] [display-kind] [,...]
Parameters
display-name
Specifies the display to be created or modified.
If you are creating a new display, specify a name that is not already
used as a display name.
If you are modifying an existing display, you can specify any of the
following entities:
- A predefined display:
SRC
OUT
PROMPT
INST
REG
FREG (Alpha and I64 only)
IREG
- A display previously created with the DISPLAY command
- A display built-in symbol:
%CURDISP
%CURSCROLL
%NEXTDISP
%NEXTINST
%NEXTOUTPUT
%NEXTSCROLL
%NEXTSOURCE
You must specify a display unless you use /GENERATE (parameter
optional), or /REFRESH (parameter not allowed).
You can specify more than one display, each with an optional window
specification and display kind.
window-spec
Specifies the screen window at which the display is to be positioned.
You can specify any of the following entities:
- A predefined window. For example, RH1 (right top half).
- A window definition previously established with the SET WINDOW
command.
- A window specification of the form (start-line, line-count[,
start-column, column-count]). The specification can include
expressions which can be based on the built-in symbols %PAGE and %WIDTH
(for example, %WIDTH/4).
If you omit the window specification, the screen position depends on
whether you are specifying an existing display or a new display:
- If you are specifying an existing display, the position of the
display is not changed.
- If you are specifying a new display, it is positioned at window H1
or H2, alternating between H1 and H2 each time you create another
display.
display-kind
Specifies the display kind. Valid keywords are as follows:
|
DO (
command[;...])
|
Specifies an automatically updated output display. The commands are
executed in the order listed each time the debugger gains control.
Their output forms the contents of the display. If you specify more
than one command, the commands must be separated by semicolons.
|
|
INSTRUCTION
|
Specifies an instruction display. If selected as the current
instruction display with the SELECT/INSTRUCTION command, it displays
the output from subsequent EXAMINE/INSTRUCTION commands.
|
|
INSTRUCTION (
command)
|
(VAX only) Specifies an automatically updated instruction display. The
command specified must be an EXAMINE/INSTRUCTION command. The
instruction display is updated each time the debugger gains control.
|
|
OUTPUT
|
Specifies an output display. If selected as the current output display
with the SELECT/OUTPUT command, it displays any debugger output that is
not directed to another display. If selected as the current input
display with the SELECT/INPUT command, it echoes debugger input. If
selected as the current error display with the SELECT/ERROR command, it
displays debugger diagnostic messages.
|
|
REGISTER
|
Specifies an automatically updated register display. The display is
updated each time the debugger gains control.
|
|
SOURCE
|
Specifies a source display. If selected as the current source display
with the SELECT/SOURCE command, it displays the output from subsequent
TYPE or EXAMINE/SOURCE commands.
|
|
SOURCE (
command)
|
Specifies an automatically updated source display. The command
specified must be a TYPE or EXAMINE/SOURCE command. The source display
is updated each time the debugger gains control.
|
You cannot change the display kind of the PROMPT display.
If you omit the display-kind parameter, the display
kind depends on whether you are specifying an existing display or a new
display:
- If you specify an existing display, the display kind is not changed.
- If you specify a new display, an OUTPUT display is created.
Qualifiers
/CLEAR
Erases the entire contents of a specified display. Do not use this
qualifier with /GENERATE or when creating a new display.
/DYNAMIC (default)
/NODYNAMIC
Controls whether a display automatically adjusts its window dimensions
proportionally when the screen height or width is changed by a SET
TERMINAL command. By default (/DYNAMIC), all user-defined and
predefined displays adjust their dimensions automatically.
/GENERATE
Regenerates the contents of a specified display. Only automatically
generated displays are regenerated. These include DO displays, register
displays, source (cmd-list) displays, and instruction
(cmd-list) displays. The debugger automatically regenerates
all these kinds of displays before each prompt. If you do not specify a
display, it regenerates the contents of all automatically generated
displays. Do not use this qualifier with /CLEAR or when creating a new
display.
/HIDE
Places a specified display at the bottom of the display pasteboard
(same as /PUSH). This hides the specified display behind any other
displays that share the same region of the screen. You cannot hide the
PROMPT display.
/MARK_CHANGE
/NOMARK_CHANGE (default)
Controls whether the lines that change in a DO display each time it is
automatically updated are marked. Not applicable to other kinds of
displays.
When you use /MARK_CHANGE, any lines in which some contents have
changed since the last time the display was updated are highlighted in
reverse video. This qualifier is particularly useful when you want any
variables in an automatically updated display to be highlighted when
they change.
The /NOMARK_CHANGE qualifier (default) specifies that any lines that
change in DO displays are not to be marked. This qualifier cancels the
effect of a previous /MARK_CHANGE on the specified display.
/POP (default)
/NOPOP
Controls whether a specified display is placed at the top of the
display pasteboard, ahead of any other displays but behind the PROMPT
display. By default (/POP), the display is placed at the top of the
pasteboard and hides any other displays that share the same region of
the screen, except the PROMPT display.
The /NOPOP qualifier preserves the order of all displays on the
pasteboard (same as /NOPUSH).
/PROCESS[=(process-spec)]
/NOPROCESS (default)
Used only when debugging multiprocess programs (kept debugger only).
Controls whether the specified display is process specific (that is,
whether the specified display is associated only with a particular
process). The contents of a process-specific display are generated and
modified in the context of that process. You can make any display
process specific, except the PROMPT display.
The /PROCESS=(process-spec) qualifier causes the specified
display to be associated with the specified process. You must include
the parentheses. Use any of the following process-spec forms:
|
[%PROCESS_NAME]
proc-name
|
The process name, if that name contains no space or lowercase
characters. The process name can include the asterisk (*) wildcard
character.
|
|
[%PROCESS_NAME] "
proc-name"
|
The process name, if that name contains space or lowercase characters.
You can also use apostrophes (') instead of quotation marks (").
|
|
%PROCESS_PID
proc-id
|
The process identifier (PID, a hexadecimal number).
|
%PROCESS_NUMBER
proc-number
(or %PROC
proc-number)
|
The number assigned to a process when it comes under debugger control.
Process numbers appear in a SHOW PROCESS display.
|
|
proc-group-name
|
A symbol defined with the DEFINE/PROCESS_GROUP command to represent a
group of processes. Do not specify a recursive symbol definition.
|
|
%NEXT_PROCESS
|
The process after the visible process in the debugger's circular
process list.
|
|
%PREVIOUS_PROCESS
|
The process previous to the visible process in the debugger's circular
process list.
|
|
%VISIBLE_PROCESS
|
The process whose call stack, register set, and images are the current
context for looking up symbols, register values, routine calls,
breakpoints, and so on.
|
The /PROCESS qualifier causes the specified display to be associated
with the process that was the visible process when the DISPLAY/PROCESS
command was executed.
The /NOPROCESS qualifier (which is the default) causes the specified
display to be associated with the visible process, which might change
during program execution.
If you do not specify /PROCESS, the current process-specific behavior
(if any) of the specified display remains unchanged.
/PUSH
/NOPUSH
The /PUSH qualifier has the same effect as /HIDE. The /NOPUSH qualifier
preserves the order of all displays on the pasteboard (same as /NOPOP).
/REFRESH
Refreshes the terminal screen. Do not specify any command parameters
with this qualifier. You can also use Ctrl/W to refresh the screen.
/REMOVE
Marks the display as being removed from the display pasteboard, so it
is not shown on the screen unless you explicitly request it with
another DISPLAY command. Although a removed display is not visible on
the screen, it still exists and its contents are preserved. You cannot
remove the PROMPT display.
/SIZE:n
Sets the maximum size of a display to n lines. If more than
n lines are written to the display, the oldest lines are lost
as the new lines are added. If you omit this qualifier, the maximum
size of the display is as follows:
- If you specify an existing display, the maximum size is unchanged.
- If you are creating a display, the default size is 64 lines.
For an output or DO display, /SIZE:n specifies that the
display should hold the n most recent lines of output. For a
source or instruction display, n gives the number of source
lines or lines of instructions that can be placed in the memory buffer
at any one time. However, you can scroll a source display over the
entire source code of the module whose code is displayed (source lines
are paged into the buffer as needed). Similarly, you can scroll an
instruction display over all of the instructions of the routine whose
instructions are displayed (instructions are decoded from the image as
needed).
Description
You can use the DISPLAY command to create a display or to modify an
existing display.
To create a display, specify a name that is not already used as a
display name (the SHOW DISPLAY command identifies all existing
displays).
By default, the DISPLAY command places a specified display on top of
the display pasteboard, ahead of any other displays but behind the
PROMPT display, which cannot be hidden. The specified display thus
hides the portions of other displays (except the PROMPT display) that
share the same region of the screen.
For a list of the key definitions associated with the DISPLAY command,
type Help Keypad_Definitions_CI. Also, use the SHOW KEY command to
determine the current key definitions.
Related commands:
Ctrl/W
EXPAND
MOVE
SET PROMPT
(SET,SHOW) TERMINAL
(SET,SHOW,CANCEL) WINDOW
SELECT
(SHOW,CANCEL) DISPLAY
Examples
This command shows the predefined register display, REG, at its current
window location.
| #2 |
DBG> DISPLAY/PUSH INST
|
This command pushes display INST to the bottom of the display
pasteboard, behind all other displays.
| #3 |
DBG> DISPLAY NEWDISP AT RT2
DBG> SELECT/INPUT NEWDISP
|
|
