Filesystem interfaces
The WVA offers a mechanism to access files and directories for a variety of purposes, but primarily information storage. Occasional uses might include pushing a firmware update to the WVA, or examining the system event log.
The WVA has a volume, named userfs that you can use for custom file storage. Files in this volume are stored in a hierarchical directory structure. There are several system-specific directories and files in userfs that you cannot manipulate.
In the WVA filesystem, a path refers to a specification for a directory within the volume. Individual files have a filename in a particular “path.”
Other volume names correspond to storage space on USB devices. An example USB volume name is sda1.
For consistency with a wide range of existing Digi products, the WVA has two directory paths pre-existing when the system is created: /userfs/WEB and /userfs/WEB/python. Both paths are writable, and you can create custom directory trees below these paths.
Note The WVA filesystem interface is used to manipulate specific files in the embedded system at relatively fixed paths. An external application that uses web services must know the paths to the files, and know which paths and names are directories versus files. The filesystem interface itself does not provide hints as to the types of file names found in the directory tree.
PDF
