niHWS_OpenFile

NI-HWS C Function Reference

niHWS_OpenFile

C Function Prototype

tHWS_Status niHWS_OpenFile (const char filePath[], tHWS_FilePermissions permissions, tHWS_FileHandle* fileHandle);

Purpose

Opens or creates an HWS waveform file. The file must be closed with the niHWS_CloseFile function.

Parameters

Name Type Description
filePath const char[] Specifies the path and filename of the HWS file to create or open. The .hws extension is typically used for HWS files, although using this extension is optional.
permissions tHWS_FilePermissions Specifies file access options

Defined Values

niHWS_Val_ReadOnly—Opens an existing file for reading. An error is returned if the specified file does not exist. An error is returned if an attempt is made to write to the file.

niHWS_Val_ReadWriteExisting—Opens an existing file for both reading and writing. An error is returned if the specified file does not exist.

niHWS_Val_ReadWriteCreateNew—Creates a new file for both reading and writing. An error is returned if the specified file already exists.

niHWS_Val_ReadWriteCreateNewAlways—Creates a new file for both reading and writing. If the specified file already exists, its contents are lost.

fileHandle tHWS_FileHandle* Refers to an open HWS file.

Return Value