Chaining find exec and a while loop

Question

I'm trying to stack a find command so that the results it returns only contains files with "warning:" or "error:" text within them. I also require those results in a specific format so I'm using exec stat for that.

I can get a version of this to work, but I need to be able to use -exec stat within the while loop to formulate a specific string, and that -exec stat is making my shell hand me the > prompt. The part that's not working is in bold below.

Separately I can get these to work. Together I cannot.

Here's an example of one I've got working:

find . -type f -exec grep -li error: {} \; | while read -r file; do ls -l "$file"; done

So now I'm trying to shoehorn that in with another process that limits the files to specific times, types etc. It's not going well:

find /my/directory/here/ -type f -name *.log -mmin -480 -mmin +60 -exec grep -li warning: {} \; -exec grep -li error: {} \; | while read -r file; do -exec stat -c "$file" '%n|%y|%x|%s|%U|%u' {} \; done

Note, the whole thing works if I remove the -exec stat from within the while loop. If I replace that with a simple ls -l, results are given back to me. Right now the shell is just giving me a command prompt.

I know I'm not doing this right but I have no ideas right now on what I should be resolving first.

Answer 1

find /my/directory/here/ -type f -name '*.log' -mmin -480 -mmin +60 \
    -exec grep -qi warning: {} \; \
    -exec grep -qi error: {} \; \
    -exec stat -c '%n|%y|%x|%s|%U|%u' {} +

That is, you don't need the actual output of the two grep command, only the exit status, so we use -q instead of -l. There is no need for a while loop. The stat may be called with multiple files, so we use -exec stat ... {} +. I have also quoted the *.log pattern to prevent it from expanding to any such name in the current directory.

Related:

• Understanding the -exec option of `find`

Another way of doing the same thing:

find /my/directory/here/ -type f -name '*.log' -mmin -480 -mmin +60 \
    -exec sh -c '
        for pathname do
            if grep -qi warning: "$pathname" &&
               grep -qi error: "$pathname"
            then
                stat -c "%n|%y|%x|%s|%U|%u" "$pathname"
            fi
        done' sh {} +

This uses find as a pathname generator for a for loop running in a child shell. This would however call stat once for each file that contains matches for both patterns, so it's slightly less efficient.

Answer 2

GNU's grep(1) can do recursive pattern matching:

grep -R warning that-dir

checks all files under that-dir.