Open/Create/Replace Datalog Function

Owning Palette: Datalog Functions

Requires: Base Development System

Opens an existing datalog file, creates a new datalog file, or replaces an existing datalog file, programmatically or interactively using a file dialog box. This function does not work for files inside an LLB.

You can optionally specify a dialog prompt or default filename. Use this function with the intermediate Write Datalog or Read Datalog functions. Use the Close File function to close the reference to the file.

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record type can be any data type. Wire a cluster matching the record data type and cluster order to this input when creating datalog files.
prompt is the message that appears above the list of files and directories or folder in the file dialog box.
datalog path is the absolute path to the file. If you do not wire datalog path, the function displays a dialog box from which you can select a file. If you specify an empty or relative path, this function returns an error.
operation is the operation to perform. Error 43 occurs if you cancel the dialog box.

0open (default)—Opens an existing file. Error 7 occurs if the file cannot be found.
1replace—Replaces an existing file by opening the file and setting its end of file to 0.
2create—Creates a new file. Error 10 occurs if the file already exists.
3open or create—Opens an existing file or creates a new file if one does not exist.
4replace or create—Creates a new file or replaces a file if it exists. This VI replaces a file by opening the file and setting its end of file to 0.
5replace or create with confirmation—Creates a new file or replaces a file if it exists and you give permission. This VI replaces a file by opening the file and setting its end of file to 0.
access specifies how you plan to access the file.

0read/write (default)
1read-only
2write-only
error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
refnum out is the reference number of the open file. The value is Not A Refnum if the file cannot be opened.
cancelled is TRUE if you cancel the file dialog box or if you do not select the replacement in an advisory dialog box.
error out contains error information. This output provides standard error out functionality.