/sys$common/syshlp/helplib.hlb CC, Run-time functions, derror  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Returns a string describing the last error that occurred from a
  call to dlopen, dlclose, or dlsym.

  Syntax:

       #include <stdio.h>

       char *dlerror(void);