The supported POSIX functions are listed in . These are divided into four groups. First, the functions which operate on file objects (
FS_FILEs) are grouped under file access (or simply file) functions. An application stores information in a file system by creating a file or appending new information to an existing file. At a later time, this information may be retrieved by reading the file. Other functions support these capabilities; for example, the application can move to a specified location in the file or query the file system to get information about the file.
A separate set of file operations (or entry) functions manage the files and directories available on the system. Using these functions, the application can create, delete and rename files and directories.
The entries within a directory can be traversed using the directory access (or simply directory) functions, which operate on directory objects (FS_DIRs). The name and properties of the entries are returned within a struct fs_dirent structure.
The final group of functions is the working directory functions. For information about using file and path names, see µC/FS File and Directory Names and Paths.