Kernverknüpfungen

Kernverknüpfungen, also known as kernel links or hard links in English, are a fundamental concept in many file systems, particularly Unix-like systems such as Linux and macOS. A kernverknüpfung is essentially a directory entry that points to an inode, which is a data structure containing metadata about a file, including its location on the disk. When a kernverknüpfung is created, it doesn't create a new copy of the file's data; instead, it creates a new name or path that refers to the exact same data and metadata as another existing file.

This means that all kernverknüpfungen to the same inode are indistinguishable from the original file. If a file is modified through any of its kernverknüpfungen, the changes are reflected in all other kernverknüpfungen because they all point to the same underlying data. Similarly, deleting a kernverknüpfung does not remove the file's data until the last kernverknüpfung pointing to that inode is deleted. The inode itself keeps a count of how many kernverknüpfungen point to it.

Kernverknüpfungen are distinct from symbolic links (symlinks), which are a special type of file that contains a text string which is interpreted as a path to another file. A symbolic link is a separate file with its own inode, and it essentially acts as a pointer or shortcut to the target file. Kernverknüpfungen, on the other hand, are direct references to the file's data and metadata. They are typically used for tasks such as creating multiple access points to important system files without duplicating them, saving disk space, and ensuring that modifications to a file are immediately visible across all its references.