Only filenames matching access.log should be returned.

Unfortunately, since shopt globstar is disabled I ended up needing to do this:

    grep 500 $(find . -type f -iname "access.log*")

You could also include "shopt -s globstar; " at the beginning of your line.

grep -r 500 --include access.log

That returns the filenames in the format "./access.log" but it wanted "access.log". It's a bug.

I used echo -e 'access.log\naccess.log.1\nREADME'. :D

Gotcha. Thanks.

Hahahaha I did the exact same thing

You are: grep matches strings, not integers.

    grep -rl '500'

works just fine.

There is no concept of an integer on an argument vector. Quoting in bash just escapes IFS characters (usually whitespace) to control whether to include them in a given argument on the vector, but these arguments (as passed to exec) are always character strings (with or without quoting).

Interestingly enough

grep -rl "500" .

doesn't work because it returns with the "./".