Because the interfaces of the Ext2fs library are so abstract and general, new programs which require direct access to the Ext2fs filesystem can very easily be written. For example, the Ext2fs library was used during the port of the 4.4BSD dump and restore backup utilities. The Ext2fs library provides access to several classes of operations. The first class are the filesystem-oriented operations. A program can open and close a filesystem, read and write the bitmaps, and create a new filesystem on the disk.
Functions are also available to manipulate the filesystem's bad blocks list.
The second class of operations affect directories. A caller of the Ext2fs library can create and expand directories, as well as add and remove directory entries. Functions are also provided to both resolve a pathname to an inode number, and to determine a pathname of an inode given its inode number. The final class of operations are oriented around inodes. It is possible to scan the inode table, read and write inodes, and scan through all of the blocks in an inode.