HP 3000 Manuals HP 3000 Manuals
DISPLAY
Is a Symbolic Debug command that causes the current contents of specified
data-items to be displayed on your terminal.
Syntax
[ O[CTAL] ]
{rec-item [USING t1[,t2]...]}[ I[NTEGER] ][|FOR| n |ITEMS|]
DI[SPLAY] { data-item }[ C[HARACTER] ]
{"literal" }[ H[EXADECIMAL]]
Parameters
Data-item Any COBOL data name or index name defined in the COBOL
(COBOL) source program. A data-item may be qualified with:
(1) OF,
(2) IN,
(3) subscript (must be an integer value), or
(4) periods separating the data names, where the most
significant data name is specified first.
If data-item is subscripted, the subscript must be an
integer value and not a variable. If no subscript has
been used, a subscript of 1 will be assumed.
You cannot reference a data-item in a program or
subprogram other than the one that is currently
executing.
Data-item Any Pascal variable declared in the source program.
(Pascal) Standard Pascal selectors are used to qualify arrays and
records.
Data-item Any FORTRAN data name defined in the source program.
(FORTRAN) Standard FORTRAN delimiters are used in referencing
array elements.
To reference a variable outside the currently running
program or subprogram, the variable must be in a common
block.
Literal Displays the delimited string. Although double quotes
are not valid in standard Pascal, double quotes and
single quotes are allowed as delimiters.
If a delimiter is a character in the literal, it must
appear twice consecutively.
OCTAL INTEGER These keyword options override the implied format of the
CHARACTER specified data-item. If the CHARACTER option is used,
HEXADECIMAL the contents of the entire item are displayed as a
continuous string of USASCII characters. Non-printing
characters are replaced by a period.
Rec-item A data-item of Record type.
USING Pascal Only
t1[,t2]...
Used when you want to display a specific variant part of
a rec-item. t1...tn represent tag field constants that
you may specify to explicitly select different variant
parts of a record in the display.
If no tag field constant is specified in the DISPLAY
command for discriminated union records, the default is
to use the actual tag field data-item to select the
variant part. This default can be overridden by using
the tag field options constant of this command.
If no tag field constant has been explicitly specified
for free union records, the first variant of the record
will be displayed by default.
FOR n ITEMS Is used to display a specified number of table elements.
(COBOL) This clause can only be used if the data item contains
an OCCURS clause in its DATA DIVISION declaration. n is
assigned the value of 1 if this clause is not specified.
FOR n ITEMS Is used to display a specified number of characters in a
(Pascal) STRING or a specified number of elements in an ARRAY.
When this clause is specified for a string, the string
must be subscripted. n characters of the string will be
displayed beginning with the character indicated by the
subscript.
FOR n ITEMS Is used to display a specified number of elements in an
(FORTRAN) array.
Description
The DISPLAY command displays the current contents of data-items you
specify on your terminal according to formats implied by the type
descriptions in the Data Division of your source file (COBOL) or
according to the formats implied in the declarations of your source file
(Pascal or FORTRAN).
COBOL
Data Division Formats
(1) Data with PICTURE X or A is output as USASCII
characters.
(2) Picture 9 data is output in a format consistent with the
COBOL Display statement.
(3) Computational-3 packed data is output as decimal digits.
The sign bits are interpreted and output before the
number. Leading zeros are displayed.
(4) Computational binary data is output as decimal integers.
Negative signs are output preceding the number.
Table Items
If the data-item is a table item with an actual or assumed subscript (i),
the [FOR n ITEMS] clause has the effect of issuing a DISPLAY command for
each item in the table with subscript (i) to (i+n-1) inclusive.
Group Items
The default format for a group item is to display the entire item in
character format.
Pascal
The DISPLAY command displays the current contents of specified data-items
according to the formats implied in the source program's type
declarations. Only those data-items that are active at the current
breakpoint may be displayed.
Strings
The default display of variables with a structure type STRING is
CHARACTER format. The first and last characters of the string are
indicated by enclosing them in quotes. The current and maximum lengths
of the string are also shown.
Record
The default display of data-items of Record type is based on its
declaration in the source. This means that each field of the record is
treated as its own separate data-item with its own separate default
display type. You have the option of displaying the record in OCTAL,
INTEGER, CHARACTER, or HEXADECIMAL. In these cases, the data is displayed
contiguously.
If you qualify the record with a particular field, such as MyRec.Field1,
only that field will be displayed in its declared type, unless it is
overridden by the OCTAL, INTEGER, CHARACTER or HEXADECIMAL option.
If the record is a union type, the fixed and a variant part of the record
will be displayed.
Pointer
The default display of Pointer type variables is the HEX address in the
pointer or NIL.
Enumerated
Variables of enumerated type are displayed using the values associated
with that enumerated type.
Set
Data-items of the structured type SET are displayed as members of the
base type of that SET.
Boolean, Real, or Longreal
The default display for BOOLEAN type variables is TRUE or FALSE. The
default display for variables of REAL type is real. The default display
for variables of LONGREAL type is longreal.
Function or Procedure
Functions or procedures that are parameters to procedures are displayed
with the name of the procedure they are parameters to along with the
external program label as it appears in the Segment Transfer Table.
Character, Integer, and User-Defined
Displays of variables that are of CHARACTER or INTEGER type are displayed
in the corresponding default format, as are user defined variables of
CHARACTER or INTEGER base type.
Constants
The display of symbols that are simple CONSTANTS contains the value and
the source statement where it is declared. If the symbol is a structured
Constant, including Arrays, Strings, Records and Set Constants, only the
source statement will be displayed.
Withs
If execution has been suspended inside of a with construct, then fields
inside the with referenced record may be displayed by simply specifying
the field names.
Using Clause
When displaying a record with fields that are records, and both contain
variant parts, the USING clause parameters are used to select which
variant of each record to display. Consider the following code and
examples:
TYPE Case1 = (V1,V2,V3);
Case2 = (V21,V22,V23);
VAR Rec : RECORD
F1 : RECORD
F1: INTEGER;
F2: INTEGER;
CASE CASE1 OF
V1: (F21 : INTEGER); {(1)}
V2: (F22 : CHAR); {(2)}
V3: (F23 : RECORD {(3)}
F1 : BOOLEAN;
F2 : REAL;
CASE CASE2 OF
V21 : (F21: INTEGER);
V22 : (F22: BOOLEAN); {(3)}
V23 : (F23: REAL);
END;
END;
F2: CHAR;
CASE CASE1 OF
V1 : (F21: REAL); {(1) BY DEFAULT}
V2 : (F22: INTEGER); {(2)}
V3 : (F23: BOOLEAN); {(3)}
END;
NOTE One cannot DISPLAY, MOVE, or DATATRACE Pascal local variables or
parameters that reference global types that have not been included
in the main outer block compile. In other words, variables or
parameters that reference newly added global types in their
subprogram compile. This may be a problem with mixed languages.
FORTRAN Default Display Data Types
Character
Character data types are displayed as USASCII characters.
Integer, Short Integer
Integer and short integer are displayed as decimal numbers.
Real, Double Precision
Real and double precision will be displayed as real or double precision
real numbers.
Logical
The default display for Logical type variables is .TRUE. or .FALSE.
Complex, Double Complex
Display will be with the Real or Double Precision number first followed
by the imaginary number (e.g., (3.4E38,1.2E10)).
Array
The data will be displayed with the type the array name was declared as.
FORTRAN arrays are row-major; a DISPLAY will increment through the row
index before incrementing the column index.
Function, Subprogram
Functions and subroutines that are parameters to subroutines are
displayed with the name of the procedure they are parameters to, along
with the external procedure or subroutine label.
Constants (Parameter)
Constants defined with the PARAMETER statement will be displayed exactly
as the constant was defined in the source program.
Example
The following DISPLAY commands illustrate the sequence that TOOLSET/XL
uses when displaying variants within nested records. The variant
displayed by each DISPLAY command is labeled with the number of that
example in the sample code above.
(1) DISPLAY REC USING V1
Displays the variant V1 located in the nested record F1 and, by default,
the variant V1 in the outer record REC.
-->Stmt #4 Var: REC Record
F1 - Record
F1 = 10
F2 = 20
F21 = 30
F2 = 'a'
F21 = 1.034000E+2
(2) DISPLAY REC USING V2, V2
Displays the variant V2 located in the nested record F1 and the variant
V2 located in the outer record REC.
-->Stmt #4 Var: REC - Record
F1 - Record
F1 = 10
F2 = 20
F22 = 'z'
F2 = 'a'
F22 = 30
(3) DISPLAY REC USING V3, V22, V3
Displays the variant V3 located in the nested record F1. Since the
variant V3 is of record type with its own variant, this command also
displays the variant V22 located in the record F23 nested 2 deep inside
REC. Lastly, this command displays the variant V3 located in the outer
record REC.
-->Stmt #4 Var: REC - Record
F1 - Record
F1 = 10
F2 = 20
F23 - Record.
F1 = TRUE
F2 = -3.4577008E+2
F22 = FALSE
F2 = 'A'
F23 = TRUE
The fixed fields for all of these records are also displayed.
![[]](../../pic3k/M010490/F04053c50.gif)
Figure 4-5. Display Command Screen (COBOL)
Pascal
Given the following:
VAR Integer_Var: INTEGER;
Boolean_Var: BOOLEAN;
Char_Var: CHAR;
Real_Var: REAL;
Longreal_Var: LONGREAL;
(1) >>DISPLAY Integer_Var
-->Stmt #101: Var: INTEGER_VAR = 1234
Displays the value of INTEGER_VAR.
(2) >>DISPLAY Boolean_Var
-->Stmt #102: Var: BOOLEAN_VAR = TRUE
Displays the value of BOOLEAN_VAR.
Given the following:
TYPE Polys = (circle, square, rectangle, triangle);
Polygon = RECORD (*fixed part and tagless variant part*)
Poly_Color: (red, yellow, blue);
CASE Polys OF
circle: (Radius: INTEGER);
square: (Side: INTEGER);
rectangle: (Length, Width: INTEGER);
triangle: (Base, Height: INTEGER);
END;
VAR Figure: Polygon;
(1) >>DISPLAY Figure
-->Stmt #76: Var: FIGURE - Record
POLY_COLOR = RED
RADIUS = 42
(2) >>DISPLAY Figure Using Rectangle
-->Stmt #75: Var: FIGURE - Record
POLY_COLOR =RED
LENGTH = 42
WIDTH = 21
Given the following:
TYPE Fruit = SET OF (apple, banana, cherry, peach, pear, pineapple); VAR
Fruits : Fruit;
(1) >>DISPLAY FRUITS
-->Stmt #34: Var: FRUITS = [APPLE, BANANA, PEAR]
FORTRAN Data Types
Given
INTEGER*4 LONG_INTEGER_VAR
INTEGER*2 SHORT_INTEGER_VAR
REAL*4 REAL_VAR
DOUBLE PRECISION DOUBLE_PREC_VAR (or REAL*8)
COMPLEX COMPLEX_VAR (or COMPLEX*8)
DOUBLE COMPLEX DOUBLE_COMPLEX_VAR (or COMPLEX*16)
LOGICAL*4 LONG_LOGICAL_VAR
LOGICAL*2 SHORT_LOGICAL_VAR
then
>>DISPLAY LONG_INTEGER_VAR
--> Stmt #101: Var: LONG_INTEGER_VAR = 1234567890
>>DISPLAY SHORT_INTEGER_VAR
--> Stmt #102: Var: SHORT_INTEGER_VAR = 32767
>>DISPLAY REAL_VAR
--> Stmt #103: Var: REAL_VAR = 3.402823E38
>>DISPLAY DOUBLE_PREC_VAR
--> Stmt #104: Var: DOUBLE_PREC_VAR = 1.79769313486231E308
>>DISPLAY COMPLEX_VAR
--> Stmt #105: Var: COMPLEX_VAR = (3.4E38,1.2E10)
>>DISPLAY DOUBLE_COMPLEX_VAR
--> Stmt #106: Var DOUBLE_COMPLEX_VAR = (1.8E308,3.8E308)
>>DISPLAY LONG_LOGICAL_VAR
--> Stmt #107: Va:r LONG_LOGICL_VAR = .TRUE.
>>DISPLAY SHORT_LOGICAL_VAR
--> Stmt #108: Var: SHORT_LOGICAL_VAR = .FALSE.
Array Types
Given
INTEGER*4 ARRAY_VAR(2:5,1:3)
(note that this is equivalent to:
INTEGER*4 ARRAY_VAR
DIMENSION ARRAY_VAR(2:5,1:3) )
then
>>DISPLAY ARRAY_VAR
--> Stmt #101: Var ARRAY_VAR
--> Starting with ARRAY_VAR[2,1].
1234 4566 12345678 9876
--> Continuing with ARRAY_VAR[2,2]
23456 121 357951 0
--> Continuing with ARRAY_VAR[2,3]
654 1 963 5
>>DISPLAY ARRAY_VAR[4,1]FOR 3 ITEMS
--> Stmt #101: Var ARRAY_VAR
--> Starting with ARRAY_VAR[4,1].
12345678 9876
--> Continuing with ARRAY_VAR[2,2]
23456
>>DISPLAY ARRAY_VAR[5,3]
--> Stmt #101: Var ARRAY_VAR[5,3] = 5
Character and Character Array Variables
Given:
CHARACTER*8 CHAR_VAR
CHARACTER*8 ARRAY_CHAR_VAR
DIMENSION ARRAY_CHAR_VAR(4,4,4)
and if the value of CHAR_VAR is 'abcdefgh', then
>>DISPLAY CHAR_VAR
--> Stmt #101:Var CHAR_VAR = 'abcdefgh'
>>DISPLAY CHAR_VAR(1) FOR 3 ITEMS
--> Stmt #101:Var CHAR_VAR = 'abc'
If the value of ARRAY_CHAR_VAR(1,1,2) is 'ijklmnop', then
>>DISPLAY ARRAY_CHAR_VAR(1,1,2)
--> Stmt #101: Var ARRAY_CHAR_VAR = 'ijklmnop'
>>DISPLAY ARRAY_CHAR_VAR(1,1,2)(5) FOR 4 ITEMS
--> Stmt #101:Var ARRAY_CHAR_VAR = 'mnop'
>>DISPLAY ARRAY_CHAR_VAR(3,4,1) FOR 5 ITEMS
--> Stmt #101: Var ARRAY_CHAR_VAR
--> Starting with ARRAY_CHAR_VAR(1,1,1)
ARRAY_CHAR_VAR[3,4,1]
ARRAY_CHAR_VAR[4,4,1]
ARRAY_CHAR_VAR[1,1,2]='ijklmnop'
ARRAY_CHAR_VAR[2,1,2]
ARRAY_CHAR_VAR[3,1,2]
Common Blocks
Given:
INTEGER*2 I,J
COMMON /BLOCKA/I(4),J(6),ALPHA,SAM
CHARACTER*4 ALPHA
then
>>DISPLAY BLOCKA
--> Stmt #101: COMMON BLOCK:BLOCKA
I - ARRAY
--> Starting with I(1)
0 1234 45 3
J - ARRAY
--> Starting with J(1)
1 23 45 67 87 5
ALPHA = 'abcd'
SAM = 90.00