Inodetabeller

Inodetabeller, often referred to as inode tables, are a fundamental data structure used in Unix-like file systems to manage file system information. Each file and directory on a file system is represented by an inode, which stands for "index node." The inodetabell is essentially an array of these inodes.

Each inode contains crucial metadata about a file or directory, such as its permissions, owner, group, size, timestamps (creation, modification, access), and importantly, pointers to the actual data blocks that store the file's content. The inode itself does not store the file's name; that information is typically found within the directory entry that points to the inode.

When a user accesses a file, the operating system first consults the directory structure to find the file's name and its corresponding inode number. It then uses this inode number to locate the correct inode in the inodetabell. Once the inode is retrieved, the system can access the file's metadata and, if necessary, the data blocks it points to.

The size and number of inodes on a file system are usually determined at the time the file system is created. If a file system runs out of inodes, it becomes impossible to create new files or directories, even if there is available disk space. This is why a full file system can occur even when reported disk usage is not at its maximum. File system utilities like `mkfs` are used to specify the inodetabell's parameters during formatting.