vfs.open-file-system
Declaration export external file function open-file-system
value string filename
on value directory on-dir optional
for value integer access-type optional initial {read-mode}
Argument definitions
- filename
- The path to the file to be opened.
- on-dir
- A connected vfs.directory object. If this parameter is specified the filename parameter is interpreted relative to the vfs.directory and must be expressed as a relative URL.
- access-type
- An integer constant signifying the desired mode of access. The default value is vfs.read-mode.
Purpose
You can use vfs.open-file-system
to open a file. vfs.open-file-system
creates a vfs.file object that represents the file, and which can be used with various OMVFS functions to manipulate the file.
You may specify the mode in which the file is opened. The default mode is read mode. The following modes are available:
- vfs.read-mode - open the file in read-only mode. You can only read from the file.
- vfs.write-mode - allows only writing to the file. File is truncated to byte 0 when opened.
- vfs.read-write-mode - allows for both reading and writing to the file. The cursor is positioned at the first byte of the file.
- vfs.read-write-append-mode - allows both reading and writing of the file. The cursor is positioned after the last byte of the file.
- vfs.write-append-mode - file opened for writing only. The cursor is positioned after the last byte of the file.
This function is identical to vfs.open
except that non-file URLs are not supported.
Exceptions
The following exceptions may occur:
- VFS001 The requested function is not supported for the type of connection
- VFS004 The specified name 'X' exceeds system length limits
- VFS100 The vfsDir object must be connected before it can be used
- VFS105 The path 'X' is not a valid absolute or relative path
- VFS111 The URL 'X' contains invalid encoding
- VFS201 An invalid value was specified for the file access
- VFS300 Generic operating system error
- VFS306 The file 'X' does not exist