The following topics are covered:
In Natural, session parameters are used:
to specify certain characters,
to set processing time limits,
to set a particular response for a given condition,
to set various size limits,
to determine various aspects of output reports.
At the installation of Natural, the Natural administrator sets these parameters to default values which are then valid for all users of Natural.
Natural session parameters can be set in several ways:
via the default Natural parameter file NATPARM, which is set when Natural is installed;
via dynamic parameters specified when invoking Natural (as described in your Natural Operations documentation);
via a SET GLOBALS
statement (in reporting mode only);
via a FORMAT statement;
via parameter specification within statements where parameters also are evaluated,
for example, INPUT, DISPLAY, WRITE;
via terminal commands.
Instead of the parameter values ON and OFF, you can also
specify T (true) or F (false) respectively.
You can change certain parameters for the duration of a single program (report). This
is done by using a FORMAT
statement in the program, which will override the session-wide settings for these
parameters.
FORMAT AL=10 HC=R
Parameters set with a FORMAT
statement apply until the end of the executed program, unless they are changed with
another FORMAT statement in the program.
Not all session parameters can be changed at program level, while several parameters that can be specified at program level cannot be specified at session level; most of the latter are parameters which affect the format of an output report.
Most of the parameters you can change with a FORMAT statement you can also change for an
individual statement; for example, for a particular DISPLAY, WRITE, INPUT or REINPUT statement.
This is done by specifying the parameter (in parentheses) after the statement name.
DISPLAY (SF=4) NAME JOB-TITLE CURR-CODE SALARY
A parameter set at statement level applies only to the statement in which it is specified. The setting at statement level overrides, for that statement only, all other settings of that parameter at other levels.
Within a DISPLAY, WRITE, INPUT or REINPUT statement, you can also change
some parameters for an individual field or output element.
This is done by specifying the parameter (in parentheses) after the field name.
DISPLAY NAME (AL=10) JOB-TITLE CURR-CODE SALARY
The parameter value then applies only to that field. The setting at field level overrides, for that field only, all other settings of that parameter at other levels. However, only some of the parameters that can be set at statement level can also be set at field level.
Parameters specified with the statements DISPLAY, FORMAT, PRINT, INPUT, REINPUT, WRITE, WRITE
TITLE and WRITE
TRAILER are processed during program compilation and are therefore
included in the corresponding object module for the program.
The following hierarchy is used for evaluation:
Parameters set at element/field (highest priority)
Parameters set at statement level
Parameters set with a FORMAT
statement
The default parameter settings (lowest priority)
Parameters set with a SET
GLOBALS statement cause the execution time environment to be modified.
These modifications remain in effect until overridden by another SET GLOBALS
statement.