Example - opening file

• Function do_sys_open():

• • Get unused file descriptor
  • Perform path lookup using namei/ path_lookup functions (open_namei() and do_path_lookup())
  • • get root
    • get directory entry - read using FS-specific function if not present in cache, calls iget in superblock if inode not present in cache
    • if directory – lookup name in directory
    • cross mount points, follow symlinks, ...
  • Call filesystem-specific open routine from file_operations (__dentry_open())