Sorry, but the TESTCOVER.LIB is an import library for linking to Windows applications only.
TESTCOVER is supported in Unix/Linux environments.
If you look in the documentation for Visual COBOL Eclipse 2.1 Update 1 for Linux here: it will provide a link to the Server Express 6.0 docs where you will find the information for using the testcover tools from a Unix command line.
The tools work the same way in Visual COBOL as they did in Server Express.
Thanks.