Set Data File Position
Sets the read-write position in an open data file.
See also
Options
- File ID is a numeric expression that specifies the file ID of an open data file.
- New position is a numeric expression that specifies the data file's new read-write position.
Compatibility
Product | Supported |
FileMaker Pro | Yes |
FileMaker Go | Yes |
FileMaker WebDirect | No |
FileMaker Server | Yes |
FileMaker Cloud | Yes |
FileMaker Data API | No |
Custom Web Publishing | Yes |
Originated in version
18.0
Description
The read-write position is the number of bytes from the beginning of the file at which to start reading or writing data. At the beginning of a file, the read-write position is 0. At the end of a file, the position is the same as the file size (see Get File Size script step).
Notes
- If you specify a negative value for New position, the Get(LastError) function returns an error.
Example 1
Sets the read-write position of an open file with file ID of 2 to the value stored in a variable.
Set Data File Position [ File ID: 2 ; New position: $position ]
Example 2
Writes the contents of the Utilities::Log Entry field to the end of the file named change.log that is in the Documents folder.
Set Variable [ $file ; Value: Get ( DocumentsPath ) & "change.log" ]
Get File Exists [ "$file" ; Target: $fileExists ]
If [ not $fileExists ]
Exit Script [ Text Result: ]
End If
Get File Size [ "$file" ; Target: $fileSize ]
Open Data File [ "$file" ; Target: $fileID ]
Set Data File Position [ File ID: $fileID ; New position: $fileSize ]
Write to Data File [ File ID: $fileID ; Data source: Utilities::Log Entry ; Write as: UTF-8 ; Append line feed ]