copy_and_remove_files.md

3. Copy and remove files

Please go to the directory exercise_3.

3.1. Create a directory and copy a file to it.

To find characters seven and eight, you need to create a subdirectory named solution in exercise_3/ and copy the file code.txt to it. For creating directories, you can use the command

mkdir <directory name>

For copying, you can use the command

cp <filename from> <filename to>

Use ls solution/ afterwards to see whether the file is there. The program

./check_code

will give you the solution.

3.2. Removing files

In the same directory, there is a file junk.txt that does not contain anything useful, and should be deleted. To do so, use the command

rm <filename>

Also, there are more files to be deleted in the data directory. To remove more than one file at once, you can use '*' as a wildcard, i.e. 'rm pro*' will delete all of profile, 'protein.txt and prototype.doc. To get characters nine and ten, please run the program

./check_junk

after removing the files.

WARNING

On Unix, it is not possible to undelete files!

Hint

To remove an empty directory, you can use

rmdir <directory name>

To delete a directory and everything in it, the command rm -r exists. In combination with the '*' symbol, this is dangerous, because it gives you the possibility to wipe out all your data with a single command (e.g. if you type the wrong directory by accident). Thus, first make a backup and then play with this command.