Check the format of the magic file (files argument is invalid with
Run file on the filenames in list.
Do not follow symbolic links.
Use file as the magic file instead of /etc/magic.
Many file types are understood. Output lists each filename, followed by a brief classification such as:
ascii text c program text c-shell commands data empty iAPX 386 executable directory [nt]roff, tbl, or eqn input text shell commands symbolic link to ../usr/etc/arp
List all files that are deemed to be nroff/troff input:
file * | grep roff