# Recitation6 ## Topics Today - Inode - Hard link - Soft link - Process # Inode ## What's Inode - An "index node" (inode) is a data structure in Unix-like file systems. - It stores metadata about files and directories. ## Attributes - File type (regular file, directory, symlink, etc.) - Permissions (read, write, execute) - Ownership (user and group) - Size - Timestamps (modification, access, change) - Disk block pointers - Link count ## How to check Inode ```bash= ls -l myfile.txt ``` or ```bash= stat myfile.txt ``` # Hard Link Hard link points to some space on disk. directories have 2 or more hard links - 1 from its parent directory - 1 from itself (.) - 1 from each of its subdirectories (via ..) ```bash= mkdir mydir stat mydir ``` or ```bash= ls -i mydir ``` `ln` create a new hard link for an existing file ```bash= ln myfile.txt testfile.txt ``` `rm` unlinks a file ```bash= rm myfile.txt ``` `mv` unlinks a the source file name and relinks it at the destination ```bash= mv testfile.txt myfile.txt ``` # Soft Link Symbolic link (soft link) serves as a pointer or reference to another file or directory. It's a way to create shortcuts to files or directories, allowing you to reference them using a different name or location ## Creates a symbolic link using the `ln` command with the `-s` option ```bash= ln -s myfile.txt testlink ``` Then use `stat` to check it. ``` stat testlink ``` # Process Use `top` or `htop` to check running process