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FutureBasic 5
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read field
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statement
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Syntax:
read field [#]deviceID,handleVar
Description:
This statement creates a new relocatable block in memory, reads data from the open file or serial port specified by deviceID
into the new block, and returns a handle to the block into handleVar
, which must be a long-integer variable or a Handle
variable.
The data in the file (or coming in through the serial port) must be in a particular format in order to be read properly. The first 4 bytes (at the current "file mark" position) must be a long integer which indicates the size of the block to create. This should be immediately followed by the data which is to go into the block. This is the format in which the write field
statement writes to a file; almost always, the data you read with read field
will have been created using a write field
statement.
Note:
Your program is responsible for disposing of the handle returned in handleVar
when you're finished using the block. You can use a statement such as DisposeH
or kill field
to do this.
See Also:
write field; read file; open; kill field; DisposeH