Defining a display file for DDS

When you specify positional entries for display files, you need to follow some specific rules for filling in positions 1 through 44 of the data description specifications (DDS) form.

Specify the entries in the following order to define a display file:
1. File-level entries
2. Record-level entries
3. Help-level entries
4. Field-level entries
Specify at least one record format in the file.
The maximum number of record formats in a display file is 1024. The maximum number of fields in any one record format is 32 763. The maximum number of fields that can be displayed per record is 4095. The maximum combined length of all named fields and indicators in a record format is 32 763 bytes, regardless of the usage (I, O, B, M, H, P). For more information, see Usage for display files (position 38). Also, see the Application Display Programming book for the maximum number of input-capable fields.
Note: Specify the file name through the Create Display File (CRTDSPF) command, not through DDS.

You can find an explanation of file-level, record-level, help-level, and field-level entries as well as syntax rules for specifying DDS keywords in Rules for DDS keywords and parameter values.

The following figure shows a display file example.

Figure 1. Display file example

|...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+....8
00100A* DISPLAY FILE EXAMPLE
00101A*
00102A                                      REF(PAYROLL)
00103A          R MENU
00104A          H                           HLPARA(1 1 12 80)
00105A                                      HLPRCD(RECORD1 FILEA)
00106A N01
00107AO 02        FLDA          20I 2O  2  2DSPATR(HI)
00108A            FLDB          22N 2B  3  2
00109A  72 73
00110AO 60 61 62
00111AA 63                                  DSPATR(HI)
00112A            FLDC           7Y 0B  7 20DSPATR(RI PC)
00113A  42 43
00114AO 60 61
00115AO 62                              9  2'Constant'
00116A            FLDD      R          11  2