VMS Help CC, Run-time functions, getname  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Returns the file specification associated with a file descriptor.

  Syntax:

       #include <unixio.h>

       char *getname(int file_descriptor, char *buffer,...);

  where the ...  is an optional argument that can be either 1 or 0.
  If you specify 1, getname returns the directory specification in
  OpenVMS format.  If you specify 0, getname returns the directory
  specification (path name) in UNIX style format.  If you do not
  specify this argument, getname returns the file name according to
  your current command-language interpreter.