Skip to content

2023 Boost - Week 5#


This week we do "destructive" file system stuff related and take a lot of time to review the most common dangers. Watch this is you want to keep your job once you get it.

  1. How do I create a new directory?

    mkdir NAME
  2. How do I "hide" a file or directory?

    Give it a dot (.) as the first character in name.

  3. How do I move or rename a file or directory?

    mv OLD NEW


    Be very careful when moving and renaming since you can easily clobber an existing file or directory. Don't bother with activating noclobber because it will get in your way more than help you, just become aware/paranoid about the danger.

  4. How do I move multiple files into a single directory?

    mv SOURCE... DIR

    SOURCE can be a file, directory (or path to) or a glob.


    When moving muliple SOURCEs make sure that DIR is a directory and not a file.


    Note that mv sometimes will not work because the source and destination are on different file systems.

  5. How do I list properties of a directory (instead of contents)?

    ls -lda DIR
  6. How do I safely avoid typing long or complicated names?

    Tap tab (once or twice) for tab completion.

  7. How do I remove a file?

    rm FILE


    When working with destructive commands that operate on many files try ls first to make sure it only affects the files you want.

  8. How do I create a temporary container (sandbox) just to try dangerous (stupid) things?

    podman run -it --rm
  9. How do I remove a directory?

    rmdir DIR


    Prefer rmdir over alternatives to force yourself to be sure of each individual thing that is being deleted within that directory (since rmdir will not remove directories containing).

  10. How do I remove a directory and everything under it recursively?

    rm -rf DIR


    Even though this command does not work on significant system directories (like /) it is very recursively destructive and should almost never be used. Use rmdir instead.

  11. How do I recover a broken or deleted configuration file?

    cp /etc/skel/FILE ~
  12. How do I start a new shell and replace the currently running one?

    exec bash -l
  13. How do I copy a file?

  14. How do I recusively copy a directory and subdirectories?

    cp -r SOURCE.. DIR


    This creates new files with new creation dates/times and ownership if copying from another user. Use other cp argument options when preserving them is important.