Volume Operations

Volume Operations

Five general operations can be performed on a volume:

A volume can be opened (mounted). During the opening of a volume, file system control structures are read from the underlying device, parsed and verified.

Files can be accessed on a volume. A file is a linear data sequence (‘file contents’) associated with some logical, typically human-readable identifier (‘file name’). Additional properties, such as size, update date/time and access mode (e.g., read-only, write-only, read-write) may be associated with a file. File accesses constitute reading data from files, writing data to files, creating new files, renaming files, copying files, etc. File access is accomplished via file module-level functions, which are covered in Chapter 6, “Files” on page 83.

Directories can be accessed on a volume. A directory is a container for files and other directories. Operations include iterating through the contents of the directory, creating new directories, renaming directories, etc. Directory access is accomplished via directory module-level functions, which are covered in Chapter 7, “Directories” on page 93.

A volume can be formatted. (More specifically, high-level formatted.) Formatting writes the control information for a file system to the partition on which a volume is located.

A volume can be closed (unmounted). During the closing of a volume, any cached data is written to the underlying device and associated structures are freed.

For information about using volume names, see section 4-2 “μC/FS Device and Volume Names” on page 61. For FAT-specific volume functions, see Chapter 4, “File Systems: FAT” on page 153.

1. 1. Volume API functions