How can I do many things in a single loop?

The loops you have seen so far all have a single command or pipeline in their body, but a loop can contain any number of commands. To tell the shell where one ends and the next begins, you must separate them with semi-colons:

for f in seasonal/*.csv; do echo $f; head -n 2 $f | tail -n 1; done

seasonal/autumn.csv
2017-01-05,canine
seasonal/spring.csv
2017-01-25,wisdom
seasonal/summer.csv
2017-01-11,canine
seasonal/winter.csv
2017-01-03,bicuspid

Suppose you forget the semi-colon between the echo and head commands in the previous loop, so that you ask the shell to run:

for f in seasonal/*.csv; do echo $f head -n 2 $f | tail -n 1; done

What will the shell do?

Possible answers

Print an error message.

Print one line for each of the four files.

Print one line for autumn.csv (the first file).

Print the last line of each file.

Exercise

How can I do many things in a single loop?

Instructions

Possible answers