Natural System Files

The table below lists and describes the Natural system files that are usually available in a Natural environment. The availability of the system files and the data contained in the files depends on the Software AG products installed in addition to base Natural.

The settings for the system files are defined with Natural profile parameters of the same names (exception: scratch-pad file). You can follow the hyperlinks in the table below to read details about these parameters in the Parameter Reference documentation.

System File Supplied with File Contents
FNAT Base Natural All objects required for Natural system applications.
FUSER Base Natural User-specific objects required for user-defined applications.
FPROF Base Natural Parameter profiles specified by the profile parameter PROFILE, provided no database information is supplied as subparameter of PROFILE.
Scratch-pad file Base Natural Data that is not stored explicitly as a Natural object in another system file. See also Natural Scratch-Pad File in the Operations documentation.
FDIC Base Natural Natural Data Definition Modules (DDMs).

If Predict is installed, FDIC also contains data for the Predict dictionary system.

If the Natural Development Server is installed, FDIC also contains application data and holds object locking information.

FREG Base Natural Registry data that is not stored explicitly in another system file.
FSEC Natural Security Control information required for security definitions.
FSPOOL Natural Advanced Facilities Control and spooling information required to output a report on a screen or printer and obtain print statistics.

Natural Scratch-Pad File

The Natural scratch-pad file is used to store recordings and screen captures which cannot be explicitly saved as a Natural object in the Natural FNAT or FUSER system file.

In contrast to FNAT and FUSER, a scratch-pad file is not mandatory in a Natural session. However, you must define a scratch-pad file if you are working with read-only access to system files (profile parameter ROSY=ON). Otherwise, the recordings and screen capture cannot be stored and a corresponding error message (NAT0106) is issued instead. The scratch-pad file is excluded from read-only access.

A reasonable estimate about the related storage requirements is hardly possible as the amount of storage used by the Recording utility and the NATPAGE utility (for screen captures) cannot be calculated beforehand. However, the scratch-pad file size required at your site can be estimated with a better understanding of the types of records that are stored on it. The content of the scratch-pad file is described in the following section:

Related Topic:

Defining a Scratch-Pad File in the Installation for z/OS, Installation for z/VSE and Installation for BS2000 documentation.


The Recording utility is activated using terminal commands as described in the Utilities documentation. Recordings are stored like Natural source programs (or other object types). The size of a recording depends on how many screen inputs have been done during a recording session. Recordings are like programs related to a library.

Currently, it is not possible to list recordings on the scratch-pad file by using the Natural LIST system command. SYSMAIN can be used, though, to list and maintain the recordings stored on the scratch-pad file. To store the recordings on the FNAT/FUSER file instead of on the scratch-pad file, set the profile parameter RFILE.

Recordings which are being stored on the system file FNAT or FUSER are affected (interrupted) by transaction backouts (BTs) which are issued in the user's application programs. This is a very common problem encountered by users of the recording facility and it can be avoided by using the scratch-pad file.

Screen Captures - NATPAGE

The screen capturing utility NATPAGE can be used to store screen images (in chronological sequence of their appearance) on the scratch-pad file. NATPAGE can be activated with the terminal command %P. From the moment %P is issued, all screens presented to the end user are stored onto the scratch-pad file (if it has been defined for your session) until the terminal command %O is entered. The captured screens can be displayed using the terminal command %E.

For each screen image, the current content of the page buffer and the page attribute buffer is stored. This means that the amount of data being stored depends on the settings of the profile parameters PS/LS for the session and, of course, on the number of screen images. The number of possible screens per user session depends on the profile parameter PD (default is 50; valid values are 0-255).

The size of the page buffer can be calculated as:


The size of the page attribute buffer is determined dynamically.

File Maintenance

The scratch-pad file does not need any maintenance, provided it is of sufficient size.

  • Recordings on the scratch-pad file can be deleted, copied, moved and listed by using the utility SYSMAIN.

  • Captured screens can be deleted by using the %E terminal command.

  • Saved screen images, however, cannot be maintained in Natural at all.

Space on the scratch-pad file can be reclaimed by refreshing it with Adabas utilities in times of non-activity without affecting subsequent Natural sessions which are using the scratch-pad file.