Please follow and complete the free online Command Line Crash Course tutorial or Codecademy's Learn the Command Line. These are helpful tutorials. Each "chapter" focuses on a command. Type the commands you see in the Do This section, and read the You Learned This section. Move on to the next chapter. You should be able to go through these in a couple of hours.
Here's a list of items with which you should be familiar:
- show current working directory path
- creating a directory
- deleting a directory
- creating a file using
touchcommand - deleting a file
- renaming a file
- listing hidden files
- copying a file from one directory to another
Make a cheat sheet for yourself: a list of at least ten commands and what they do. (Use the 8 items above and add a couple of your own.)
show current working directory: pwd create a directory: mkdir[dir] delete a directory: rmdir[dir] (if empty) or rm -R [dir] (if directory not empty) create a file using touch: touch [file] deleting a file: rm [file] or rm -i[file] with confirmation renaming a file: mv [file] [new filename] listing hidden files: ls -a copying a file from one directory to another: cp [file] [dir] pushing output to a file to a file: > [file] changing directory: cd[dir] last command written: up arrow auto-fill: tab
What do the following commands do:
ls
ls -a
ls -l
ls -lh
ls -lah
ls -t
ls -Glp
ls: lists the files and directory in current directory ls -a: lists all files including hidden ones ls -l: displays files in long format ls -lh: displays in long format and uses unit suffixes for size of file ls -lah: displays all of the files, including hidden, using unit suffixes in long format ls -t: displays time modified files first before sorting by alphabetical order ls -Glp: Enables color output, in long format, with a /after the directories
Explore these other ls options and pick 5 of your favorites:
ls -d: displays only directories ls -R: displays subdirectories ls -t: displays newest files first ls -c: displays files by timestamp ls -r: displays files in reverse order
What does xargs do? Give an example of how to use it.
Xargs is a command line tool that reads data from a standard input (stdin) and executes the command supplied to it. It is often used in combination with a find command for files with a certain string pattern and then pipe those results as input to a xarg command which then does something else with them. You can also use a xarg command to find directly. I'll need to play around with this tool to wrap my head around how it works.
Finding a files then piping into a xarg command which lists the results: find ./[dir] -name "*[string pattern]" -print0 | xargs -0 ls
$ xargs find -name "*.txt" - which will find all of the files with .txt as an extension in that directory