I test content of a set of data files whether they contain at least one of a set of characters which consists of printing and non-printing characters.
My last issue is detecting whether the file contains a line-feed. My GNU grep 3.0 states every input contains a LF... Why is that?
echo -n "test" | grep -UF -e $'\x0a'
Any ideas? I suspect some implicit EOL/EOF interference.