3.29 Example: unistr

   /*  exstr.c - Sample code for unistr. 
       
      Search for a substring of a string. 
   */ 
           
   #include <nunicode.h> 
   #include <assert.h> 
   
   void main(void) 
   { 
     punicode ret; 
      
     ret = unistr(L"aa bb cc dd", L"cc"); 
     assert (unicmp(ret, L"cc dd") == 0); 
     ret = unistr(L"aa bb cc dd", L"xx");   /* "xx" does not occur */ 
     assert (ret == NULL); 
   }