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
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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.