Lock Instruction

Syntax

Lock StreamNum
-or-
Lock StreamNum, RecordNum
-or-
Lock StreamNum, [start] To end

Group

File

Description

Form 1: Lock all of StreamNum.

Form 2: Lock a record (or byte) of StreamNum.

Form 3: Lock a range of records (or bytes) of StreamNum. If start is omitted then lock starting at the first record (or byte).

Note: Be sure to Unlock for each Lock instruction.
Note: For sequential files (Input, Output and Append) lock always affects the entire file.

Parameter	Description
StreamNum	Streams 1 through 255 are private to each macro. Streams 256 through 511 are shared by all macros.
RecordNum	For Random mode files this is the record number. The first record is 1. Otherwise, it is the byte position. The first byte is 1.
start	First record (or byte) in the range.
end	Last record (or byte) in the range.

See Also: Open, Unlock.

Example

Sub Main
Dim V As Variant
Open "SAVE_V.DAT" For Binary As #1
Lock #1
Get #1, 1, V
V = "Hello"
Put #1, 1, V
Unlock #1
Close #1
End Sub