FPARMS and TABLES file parameters

From m204wiki
Jump to navigation Jump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

Overview

Associated with each file are a number of parameters that determine its structure, define its privileges, and keep track of its status and usage. The categories of file parameters are:

Category Meaning
FPARMS File characteristics parameters summarize the organization, status, privileges, and field level security levels associated with the file.
TABLES File table parameters summarize information about the various tables that make up the file.

This page describes how to view, display, and set file parameters. For a listing of all the Model 204 parameters, see List of Model 204 parameters.

File parameter access

The ability to access the file-related parameters described in this page is a privilege under the control of the PRIVDEF parameter. A file manager or system manager can restrict access to the file parameters of sensitive files to qualified users only.

If the X'0001' bit of PRIVDEF is on, the user can access the file-related parameters. If it is off, the user cannot access these parameters.

The CURFILE parameter is unaffected by the PRIVDEF setting.

You can access file-related parameters through a command (VIEW or DISPLAY FILE), a SOUL function ($VIEW), or a Host Language function (IFDISP or IFEPRM). Trying to access parameters without the correct privilege generates an error message from VIEW or DISPLAY FILE; $VIEW returns a null string, and IFEPRM produces a return code of 4.

Using the VIEW command

You can display the file characteristics or table parameters with the following VIEW command options:

VIEW {FPARMS | TABLES}

You can view individual file parameters as shown in the following example:

> VIEW FILEORG FILEORG X'03' (KEY REQUIRED,SORTED) FILE ORGANIZATION

You can also use the Host Language Interface function IFEPRM to examine individual parameter values, and use the SOUL function $VIEW to return the value of a parameter to a SOUL request.

The FILEORG parameter is a flag, or bitmap, parameter, that is, a parameter whose value is the sum of the individual bits or flags that compose it. When a flag parameter is viewed, Model 204 displays a phrase that indicates the individual flag settings. The individual parameter's description page (linked from List of Model 204 parameters) include a complete list of the flags that can be set.

The previous FILEORG example indicates that the file is sorted (X'01') and that a sort key is required in every record (X'02'). Other file flag parameters include FISTAT, FOPT, OPENCTL, and SECTY.

Using the DISPLAY command

Use the DISPLAY command (or Host Language Interface function IFDISP) to display file parameters. The following form of the DISPLAY command displays all the file characteristics (FPARMS) or file table (TABLES) parameters for the specified files or all the files the user has open:

DISPLAY FILE {(FPARMS) | (TABLES)} {filename[,filename...] | ALL}

Both FPARMS and TABLES can be specified in the same command. The DEFINITIONS option of DISPLAY also includes both types of file parameters. For further description of the DISPLAY options and capabilities, refer to Defining fields manually and to DISPLAY command.

Setting file parameters

Some of the file parameters are view-only parameters; that is, you can examine them but not change them. Other parameters can be set only during file creation. You can specify the new value of the parameter in a PARAMETER statement that follows the CREATE command. (Refer to the description of file creation in Creating a file.) Other parameters can be set only during file initialization. You can specify the value of the parameter in the INITIALIZE command (see Initializing files).

You can reset some of the file parameters at any time using the RESET command. For example:

RESET BRESERVE=50

You must have ad hoc update privileges in order to reset file parameters.

If a parameter that has a minimum value is set to a value less than the minimum allowed, Model 204 sets the parameter to the minimum value and displays the following message:

*** M204.1149: parameter HAS BEEN SET TO ITS MINIMUM VALUE:value

If a parameter that has a maximum value is set to a value greater than the maximum allowed, Model 204 sets the parameter to the maximum value and displays the following message:

*** M204.1149: parameter HAS BEEN SET TO ITS MAXIMUM VALUE:value

File characteristics parameters (FPARMS)

File characteristics parameters describe the status and organization of a Model 204 file and the privileges associated with the file.

Viewing file characteristics parameters

To view parameters in the file characteristics category, enter the following command:

VIEW FPARMS

Only the file manager can set file parameters (except for those that cannot be set). CURFILE is included in both the FPARMS parameters and also in the file table parameters (TABLES).

View-only FPARMS

The following FPARMS parameters cannot be set:

CURFILE
CURLOC
FICREATE
FIFLAGS
FIFORMAT
FITRANS
SECTY

FPARMS set during file creation

The following parameters can be set during file creation:

FILEORG
IVERIFY
LANGFILE

Resettable FPARMS set by Model 204

The following parameter is set by Model 204 and can be reset by the File Manager:

FISTAT

Resettable FPARMS set during file creation

The following parameters can be set during file creation and can be reset by the File Manager:

ADDLVL
FILEMODL
FOPT
FRCVOPT
OPENCTL
PRCLDEF
PRIVDEF
READLVL
SELLVL
UPDTLVL
VERIFY

Non-resettable FPARMS set during file initialization

The following parameters are set during file initialization (the INITIALIZE command), if applicable, and cannot be reset:

HASHKEY
RECSCTY
SORTKEY

File table parameters (TABLES)

File table parameters describe the characteristics of the various tables that make up a Model 204 file.

Viewing file table parameters

To view parameters in the file table category, enter the following command:

VIEW TABLES

Only the File Manager can set the file table parameters (except for those that cannot be set). CURFILE is included in this category and also in FPARMS.

View-only TABLES parameters

The following TABLES parameters cannot be set:

ARETRIES DHIGHPG HIGHSORT OINENTRY
ASIZE DPGSUSED MSTRADD OVFLADD
BHIGHPG EHIGHPG MSTRDEL OVFLDEL
BLOWPG EOVFLADD OIDEPTH SPILLADD
BQLEN EOVFLDEL OILEAVES SPILLDEL
BREUSED EPGSUSED OILPACT XHIGHPG
CRETRIES EXTNADD OINBYTES XQLEN
CURFILE EXTNDEL OINODES XREUSED
DACTIVE FREESIZE    

TABLES parameters set during file creation

The following parameters can be set during file creation:

ASTRPPG BSIZE PDSIZE
ATRPG CSIZE PDSTRPPG
BEXTOVFL DSIZE RECPDOPT
BPGPMSTR ESIZE XRECPPG
BPGPOVFL FVFPG XSIZE
BRECPPG MVFPG  

Resettable TABLES parameters set during file creation

The following parameters can be set during file creation and can be reset by the File Manager:

BAUTOINC DAUTOINC XAUTOINC
BREUSE DPGSRES XRESERVE
BRESERVE DRESERVE XREUSE