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

  Compares two 7 bit ASCII strings for case and size, with case
  insensitivity.

  Syntax:

        #include <strings.h>

        int strncasecmp (const char *s1, const char *s2, size_t n);