bash loop all files in directory, then loop lines of each file

Question

I have

urls1.txt
urls2.txt
urls3.txt

And so on.

How can I loop all files in this directory then loop each line of these files?

What would you want to do to each line of each file? It's very seldom necessary to read in lines from a file in a shell script. It's more common to process each file through awk or sed or some such tool. See e.g. https://unix.stackexchange.com/questions/169716 — Kusalananda, Jan 14 '19 at 15:20
This seems simple enough to do even notwithstanding the truth of @Kusalananda's comment. What have you tried? How did it not work as expected or intended? — DopeGhoti, Jan 14 '19 at 15:21

score 1 · Answer 1 · edited Jan 14 '19 at 20:27

1

To answer your question as it is written you can do the following:

#!/bin/bash

for file in /path/to/files/*.txt; do
    # This will loop through each .txt file in the directory
    # setting the full file path to $file
    # I recommend adding the .txt if you know all your files
    # will have that extension otherwise the following is fine:
    # for file in /path/to/files/*; do
    while read -r line; do
        # This will loop through each line of the current file
        # and set the full line to the $line variable
        command "$line"
    done < "$file"
done

Explanations are in comments within the code

edited Jan 14 '19 at 20:27

Ralf

507
2
10

answered Jan 14 '19 at 15:34

jesse_b

37,005

IT doesnt work ./test.sh: line 16: syntax error near unexpected token while' ./test.sh: line 16: while read -r line; do' – Born vs. Me Jan 14 '19 at 15:53
@Bornvs.Me: sorry I forgot a do in the for loop, see if that fixes it. – jesse_b Jan 14 '19 at 15:55
2

It'll trim whitespace. – Kusalananda Jan 14 '19 at 15:57

bash loop all files in directory, then loop lines of each file

1 Answers1