5.4.5.1 Open Statement
Note
This section describes the implementation of MS-VBAL §5.4.5.1 Open Statement.
Syntax
| AST node | Instruction kind(s) | Notes |
|---|---|---|
| OpenStatementNode | Simple |
Mode, Access and Lock are keyword choices, not expressions. They are typed VBFileMode, VBFileAccessMode and VBFileLockMode. |
See RD-VBAL §3.4.3 File Statements.
Runtime Semantics
The session's file-channel shim holds the numbered channels Open opens. Each channel records the mode it was
opened under (RD-VBAL §5.4.5 File Statements).
The statement/mode/access table of MS-VBAL §5.4.5.1 is held once, for every file statement; see RD-VBAL §5.4.5 File Statements.
MS-VBAL §5.4.5.1 constrains the Len clause but does not say what an absent Len clause means. A Random
channel whose Open statement declared no Len clause counts positions in 128-byte records, MS-VBA's own
default record length; see RD-VBAL §5.4.5.11 Put Statement.
Implementation
| Name | Role |
|---|---|
| IFileChannels | Holds the numbered channels, each with the mode it was opened under. |
| FileStatementAccess | Holds MS-VBAL §5.4.5.1's statement/mode/access table. |
5.4.5.1.1 File Numbers
This section corresponds to MS-VBAL §5.4.5.1.1 File Numbers.
Note
Reserved. This section has no content yet.
⏮️ RD-VBAL §5.4.5 File Statements | ⏭️ RD-VBAL §5.4.5.2 Close and Reset Statements