0x02-shell_redirections

Shell, I/O Redirections and filters

In this project, I learned about using the head, tail, find, wc, sort, uniq, grep, and tr commands to redirect standard input and output and combine commands in the Shell. Further, I learned about how special characters work and how to filter text from files.

Resources

Read or watch:

• Shell, I/O Redirection
  
• Special Characters

In this project, I learned about using the head, tail, find, wc, sort,

• 0. Hello World

• 0-hello_world: Bash script that prints "Hello, World" followed by a new line to the standard output.

• 1. Confused smiley

  • 1-confused_smiley: Bash script that displays a confused smiley "(Ôo)'.

• 2. Let's display a file

  • 2-hellofile: Bash script that displays the content of the /etc/passwd file.

• 3. What about 2?

  • 3-twofiles: Bash script that displays the content of etc/passwd and /etc/hosts.

• 4. Last lines of a file

  • 4-lastlines: Bash script that displays the last 10 lines of /etc/passwd.

• 5. I'd prefer the first ones actually

  • 5-firstlines: Bash script that displays the first 10 lines of /etc/passwd.

• 6. Line #2

  • 6-third_line: Bash script that displays the third line of the file iacta.

• 7. It is a good file that cuts iron without making a noise

  • 7-file: Bash script that creates a file named exactly \*\\'"Holberton School"\'\\*$\?\*\*\*\*\*:) containing the text Holberton School ending by a new line.

• 8. Save current state of directory

  • 8-cwd_state: Bash script that writes into the file ls_cwd_content the result of the command ls -la.

• 9. Duplicate last line

  • 9-duplicate_last_line: Bash script that duplicates the last line of the file iacta.

• 10. No more javascript

  • 10-no_more_js: Bash script that deletes all the regular files (not directories) with a .js extension that are present in the current directory and all its subfolders.

• 11. Don't just count your directories, make your directories count

  • 11-directories: Bash script that counts the number of directories and sub-directories in the current directory, not including the current and parent directories but counting hidden ones.

• 12. What’s new

  • 12-newest_file: Bash script that displays the 10 newest files in the current directory, one file per line, sorted from newest to oldest.

• 13. Being unique is better than being perfect

  • 13-unique: Bash script that takes a list of words as input and only prints words that appear exactly once, one word per line, sorted.

• 14. It must be in that file

  • 14-findthatword: Bash script that displays lines containing the pattern "root" from the file /etc/passwd.

• 15. Count that word

  • 15-countthatword: Bash script that displays the number of lines containing the pattern "bin" in the file /etc/passwd.

• 16. What's next?

  • 16-whatsnext: Bash script that displays lines containing the pattern "root" and 3 lines after them in the file /etc/passwd.

• 17. I hate bins

  • 17-hidethisword: Bash script that displays all lines in the file /etc/passwd that do not contain the pattern "bin".

• 18. Letters only please

  • 18-letteronly: Bash script that displays all lines of the file /etc/ssh/sshd_config starting with a letter, including capital letters.

• 19. A to Z

  • 19-AZ: Bash script that replaces all characters A and c from input to Z and e respectively.

• 20. Without C, you would live in hiago

  • 20-hiago: Bash script that removes all letters c and C from input.

• 21. esreveR

  • 21-reverse: Bash script that reverses its input.

• 22. DJ Cut Killer

  • 22-users_and_homes: Bash script that displays all users and their home directories, sorted by users, based on the /etc/passwd file.

• 23. Empty casks make the most noise

  • 100-empty_casks: Bash script that finds all empty files and directories in the current directory and all sub-directories as follows:
    • Only the names of the files and directories are displayed.
    • Hidden files included.
    • One file name per line.

• 24. A gif is worth ten thousand words

  • 101-gifs: Bash script that lists all the files with a .gif extension in the current directory and all its sub-directories as follows:
    • Hidden files included.
    • Only regular files (not directories) listed.
    • File names displayed without extensions.
    • Files sorted by byte values, but case insensitive.
    • One file name per line.

• 25. Acrostic

  • 102-acrostic: Bash script that decodes acrostics that use the first letter of each line.

• 26. The biggest fan

  • 103-the_biggest_fan: Bash script that parses web server logs in TSV format as input and displays the 11 hosts or IP addresses which did the most requests.
  • Ordered by number of requests, with most active hosts or IP's at the top.