LogFileName - Name of disk file to which logged data is written

Description

When you start a logging operation using the start function, and the LoggingMode property is set to 'disk' or 'disk&memory', then DataChange events (records) are logged to a disk file with the name specified by LogFileName. You may specify any value for LogFileName as long as it conforms to the operating system file naming conventions. If no extension is specified as part of LogFileName, then .olf is used.

If a log file with the same name as LogFileName already exists when logging is started, the LogToDiskMode property is used to determine whether to overwrite the existing file, append records to that file, or create an indexed file based on LogFileName.

The log file is an ASCII file in comma-separated variable format, arranged as follows:

DataChange: LocalEventTime
ItemID1, Value1, Quality1, TimeStamp1
ItemID2, Value2, Quality2, TimeStamp2
...
ItemIDN, ValueN, QualityN, TimeStampN
DataChange: <LocalEventTime>
ItemID1, Value1, Quality1, TimeStamp1
ItemID2, Value2, Quality2, TimeStamp2
...
ItemIDN, ValueN, QualityN, TimeStampN
...

Characteristics

Access	Read-only while logging
Applies to	dagroup
Data type	string
Values	The default value is 'opcdatalog.olf'.

See Also

Functions

start

Properties

LoggingMode, LogToDiskMode

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