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I am trying to understand what an inode is. However, this passage from Wikipedia puzzles me:
Installation of new libraries is simple with inode filesystems. A running process can access a library file while another process replaces that file, creating a new inode, and an all new mapping will exist for the new file so that subsequent attempts to access the library get the new version. This facility eliminates the need to reboot to replace currently mapped libraries. For this reason, when updating programs, best practice is to delete the old executable first and create a new inode for the updated version, so that any processes executing the old version may proceed undisturbed.