TDMS Open Function

Owning Palette: TDM Streaming VIs and Functions

Requires: Base Package (ETS, VxWorks, Windows)

Opens a .tdms file for reading or writing. You also can use this function to create a new file or replace an existing file. Use the TDMS Close function to close the reference to the file.

Examples

	file format version specifies the file format version for the .tdms file. Refer to the NI Developer Zone for more information about the file format of .tdms files. 0 1.0 1 2.0 (default)
	file path is the full path to the file you want to open. If you use this function to create a new file, the file extension of the filename you specify in file path must be .tdms. Otherwise, this function automatically appends .tdms to the filename you specify. If you use this function to open or update an existing file, you do not have to ensure that the file extension is .tdms.
	operation specifies the operation to perform. 0 open (default)—Opens a .tdms file to write to. 1 open or create—Creates a new .tdms file or opens an existing .tdms file to configure. 2 create or replace—Creates a new .tdms file or replaces an existing .tdms file. 3 create—Creates a new .tdms file. 4 open (read-only)—Opens a read-only version of the .tdms file.
	byte order specifies the byte order, or endian format, of the data in the .tdms file. Byte order specifies whether LabVIEW represents integers in memory from most significant byte to least significant byte or vice versa. Note  If you use this function to read a .tdms file, LabVIEW reads and presents the data in the byte order of the operating platform. If you use this function to create a new .tdms file, LabVIEW writes data to the file in the byte order you specify. If you use this function to update an existing .tdms file, LabVIEW ignores this input and writes data in the byte order of that file. 0 big-endian, network order—Specifies that the most significant byte occupies the lowest memory address. 1 native, host order—Specifies that this function uses the byte order of the host computer. 2 little-endian (default)—Specifies that the least significant byte occupies the lowest memory address.
	error in (no error) describes error conditions that occur before this node runs. This input provides standard error in functionality.
	disable buffering (Windows) specifies whether LabVIEW opens, creates, or replaces a .tdms file without system buffering. The default is TRUE, which means you disable system buffering. Disable system buffering can speed up data transfers in certain situations. If you have a small amount of data to transfer, you might not notice a difference if you disable buffering. To read or write a data file to a Redundant Array of Independent Disks (RAID), consider opening the file without buffering to speed up data transfers. To read the same set of data repeatedly from the computer, consider enabling buffering.
	tdms file out generates a TDMS file reference to the .tdms file on which you performed the operation.
	error out contains error information. This output provides standard error out functionality.

Examples

Refer to the following VIs for examples of using the TDMS Open function:

• Read Channel Groups (TDMS) VI: labview\examples\file\storage.llb
• TDMS - Read data (events) VI: labview\examples\file\plat-tdms.llb
• Read TDMS File VI: labview\examples\file\storage.llb
• TDMS - Concurrent File Access VI: labview\examples\file\plat-tdms.llb