Redirect output to 'file' command

Question

Is there any way to have the file command get it's input from stdin? Specifically, I am trying to get the file type of a file in an archive, and am trying to do it in a single command. I tried this:

ar -p foo.a baz.o | file

but that does not work.

Answer 1

Use file -. The hyphen means "take input from standard input".

Answer 2

Try this one:

ar -p foo.a baz.o | xargs file