Question

I have rm -i inside a for loop but when I run it, it prints the question (“do you want to delete this?) but doesn’t stop to let me answer.

find .. -name "*.tex" | while read line; do
    printf "${line%%tex}""aux" | xargs rm -i
done

How do I fix this?

Also I was originally trying to do it by using exec like so

find ..-name "*.tex" -exec printf "${{}%%tex}""aux"\; | xargs rm -i

but I get the error “bad substitution”.

Answer 1

On Linux:

find .. -name "*.tex" | while read line; do
    rm -i "${line%%tex}aux" < /dev/tty
done

You don’t need to use xargs if you have a single argument, but you do need to access the original tty somehow while inside the loop. The above works on Linux, there are probably similar tricks on other systems.

Another (possibly more portable) way to do this is to “save” stdin before entering the while loop (assuming you’re not using fd 9 for other purposes):

exec 9<&0
find .. -name "*.tex" | while read line; do
    rm -i "${line%%tex}aux" <&9
done

Difference between the two: the first one will always try (and possibly fail) to read from the controlling tty. The other one will read from whatever stdin was outside the loop.