For sequential access, makes available the next or previous logical record from a file. For random access, makes available a specified record from a disk file.
| Opcode | Operation | File Types |
|---|---|---|
| 8D | READ(sequential) WITH NO LOCK | L S R I |
| D8 | READ (sequential) WITH LOCK | L S R I |
| D9 | READ (sequential) WITH KEPT LOCK | L S R I |
| F5 | READ (sequential) | L S R I |
| 8C | READ PREVIOUS WITH NO LOCK | R I |
| DE | READ PREVIOUS WITH LOCK | R I |
| DF | READ PREVIOUS WITH KEPT LOCK | R I |
| F9 | READ PREVIOUS | R I |
| 8E | READ (random) WITH NO LOCK | R I |
| DA | READ (random) WITH LOCK | R I |
| DB | READ (random) WITH KEPT LOCK | R I |
| F6 | READ (random) | R I |
| 8F | READ (direct) WITH NO LOCK | L S R I |
| D6 | READ (direct) WITH LOCK | L S R I |
| D7 | READ (direct) WITH KEPT LOCK | L S R I |
| C9 | READ (direct) | L S R I |
| F1 | READ (position) | L S R I |
Input Fields
| fcd-relative-key | Relative record number (R) if READ random or direct |
| fcd-key-id | Key identifier (I) |
| fcd-record-address | Pointer to the record area |
Output Fields
| fcd-file status | File status |
| fcd-current-rec-len | Current record length |
| fcd-reladdr-offset or fcd-reladdr-big | Relative byte address |