循环遍历 docker bash 命令的输出

Question

I am trying to loop through a docker bash command like this: sudo docker exec -it my-container bash -c "cd sites && ls" > output.txt which gives me expected output, when I loop through it as: cat output.txt | while read line do echo "abcd${line}def"; done cat output.txt | while read line do echo "abcd${line}def"; done cat output.txt | while read line do echo "abcd${line}def"; done it gives me output as:

defdfile1
defdfile2

in short it is overlapping after file name If I do all this without the docker command like only ls on my host it works fine, how to resolve this issue?

Answer 1

When using the -t flag docker outputs to standard out with added carriage return character. It shows as ^M with cat -vte output.txt . ( -v , --show-nonprinting shows non printing characters using ^ or M- notation)

This carriage return breaks the formatting and the lines are not processed correctly. Remove the -t flag from the command to get the correct result.