Detect whether static library is a thin archive

Question

When linking a static library as a thin archive the .o-files are not copied into the archive, but rather they are referenced with their relative path from the .a file.

How can I check if a given .a file is a thin archive or not?

Answer 1

How can I check if a given .a file is a thin archive or not?

head -1 t.a 
!<thin>

Eventually, file(1) should be able to tell you. My file-5.09 just says data.