You need to set the appropriate information in the FCD according to the operation codes that you will use. The following block sets the details required for the opening of the file.
set-fcd section. *> Initially sets up FCD for OPEN op move low-values to fcd move length of fcd to fcd-length move fcd--version-number to fcd-version move fcd--indexed-org to fcd-organization move fcd--dynamic-access to fcd-access-mode move fcd--open-closed to fcd-open-mode *> When opening a file this should be set to fcd--open-closed move fcd--recmode-variable to fcd-recording-mode move fcd--format-big to fcd-file-format move fcd--auto-lock-bit to fcd-lock-mode move 12 to fcd-name-length set fcd-filename-address to address of ex-filename set fcd-idxname-address to address of ex-index-name set fcd-key-def-address to address of ex-keydef move 10 to fcd-max-rec-length move 5 to fcd-min-rec-length set fcd-record-address to address of ex-record perform set-keydefinitions .
This section populates the FCD data area with the details required to perform an OPEN. The last line performs another section that will populate the key definition block that you defined in the last step; that section is below.
set-keydefinitions section. move low-values to ex-keydef move length of ex-keydef to key2length move 1 to key-count set component-defs to length of key-specification add 14 to component-defs move 1 to component-count move 0 to component-offset *> start of key move 5 to component-length *> key length .
This section states that there will be only one key (move 1 to key-count), and that will contain only one component (move 1 to component-count), 5 bytes in length (move 5 to component-length).
Next step is to code the call to the file handler.