Practice it end to end

Put it all together on one task. A directory has many log files, and you need to clean it up and pull some statistics without opening a single file by hand.

1. Create a working directory and generate the data:

$ mkdir ~/logs-lab && cd ~/logs-lab
$ for i in 1 2 3; do echo -e "INFO ok\nERROR fail\nINFO ok" > app$i.log; done

(We cover the for construct in detail in Part II; for now just run the line, it creates three files.)

1. Look at the result: a detailed listing and the contents of one file through less.
2. Collect every line containing ERROR from all the logs into a single file errors.txt with one command.
3. Count how many ERROR lines you ended up w