Checking an arbitrary file-content based condition with find

Question

I'd like to find and delete all core files in some large directory tree.

To do this, I'd like to match files that satisfy a particular file name pattern, like:

find . -name 'core*'

... but once such a file is found, I also want to run the file command on it to make sure it's really a core dump, something like:

file --brief --mime <filename> | grep -q 'application/x-coredump'

If that command succeeds, I'd like to delete the file. Can I do it all within find?

It's important that the behavior is "shortcut": I don't want to run file unless the command matches the pattern, since that would be very slow.

Answer 1

find + bash approach:

find / -type f -name "*core*" -exec bash -c \
'[[ `file -bi "$0"` =~ application/x-coredump ]] && echo rm "$0"' {} \;

Remove echo call if you convinced of found "needed" filenames.

---

Or even shorter - with find's -delete action:

 find / -type f -name "*core*" -exec bash -c \
'[[ `file -bi "$0"` =~ application/x-coredump ]]' {} \; -delete

Answer 2

Sure it's possible:

find . -name '*.core' -type f -exec \
    sh 'if file -bi "$1" | grep -qw ^application/x-coredump; then printf "%s\n" "$1"; fi' \
    sh {} \;

If you're happy with the result replace printf "%s\n" by rm -f.