How to unescape a text file?

Question

I have a file log.txt with this content:

systemd[1]: Starting dracut cmdline hook...\r\n[    8.759274] systemd[1]:

When I do cat log.txt output is:

systemd[1]: Starting dracut cmdline hook...\r\n[    8.759274] systemd[1]:

Expected output is 2 lines (\r\n to be replaced with visibly new line):

systemd[1]: Starting dracut cmdline hook...
[    8.759274] systemd[1]:

How to achieve this in a bash terminal?

Answer 1

Without involving any external command, you can do this using printf '%b\n' instead of cat:

printf '%b\n' "$(<log.txt)"

systemd[1]: Starting dracut cmdline hook...
[    8.759274] systemd[1]:

• %b expands backslash escape sequences in the corresponding argument
• $(<log.txt) is bash directive to get content of log.txt

Answer 2

You can use echo -e for that:

echo -e $(<log.txt)