iProgramming Restrictions [ Micro Focus COBOL System Reference, Volume 2 ] MPE/iX 5.0 Documentation
Micro Focus COBOL System Reference, Volume 2
iProgramming Restrictions
This section gives details of items of COBOL syntax that are not
implemented, areas of programming you should use with care, and
programming restrictions.
COBOL Syntax Not Implemented
The following COBOL syntax documented in the Language Reference is not
supported:
* ENTER. If statements in another language follow an ENTER
statement, they can cause spurious errors.
* RESERVE. The RESERVE clause in the File-Control entry is
documentary only.
Neither of these items is defined in the ANSI standard.
The following OS/VS COBOL syntax is not supported:
* NOMINAL KEY
* USE AFTER...GIVING data-name
Areas to Avoid
This section describes areas of programming that you should avoid or use
with care. Unpredictable results may occur when using the following
item.
ALTER. In a segmented program, you must not alter code outside the
current segment. However, if you do this, the Compiler does not report
an error. The Compiler alters the code when the segment is entered.
PERFORM Nesting
The maximum number of levels for standard PERFORM nestings is 100 in .int
code. The maximum for .gnt code depends on the memory allowed by your
operating system.
The maximum level of PERFORM nesting when animating is 254. If your
program exceeds this level, Animator will only Step, even if Zoom mode is
specified.
Parameters in USING Clause
The maximum number of parameters in the USING phrase of the PROCEDURE
DIVISION header is 126.
Size of Numbers
According to the ANSI standard, numbers are limited to 18 significant
decimal digits. All significant digits must be within 18 digits of the
decimal point.
Under the COBOL system, the result of a multiplication or division which
is greater than 36 digits gives an ON SIZE ERROR, as does the result of
an addition or subtraction which is greater than 37 digits.
The ENTRY Statement
Entry points defined using the ENTRY statement can be accessed only after
the main entry point (identified by the program-id) has been called,
unless the program is statically linked.
A nested program cannot contain ENTRY statements.
Local-Storage Section
A nested program cannot have a Local-Storage Section.
Screens Utility
The maximum number of data entries a screen can contain is 200. This can
be any combination of fields or groups. If you attempt to use more than
200 entries on a screen the following message appears:
Field table full
and the results on the existing fields are undefined. You should,
however, use groups to avoid using this many entries and to make the
generated code smaller and easier to maintain.
MPE/iX 5.0 Documentation