work6 - setvbuf

[David Burgess <dburgess@...>]

The addition of setvbuf to liolib.c is welcome, however can we
have an extra parameter to specifiy the buffer size?

liolib.c 421
-  return pushresult(L, setvbuf(f, NULL, mode[op], 0) == 0, NULL);

+  return pushresult(L, setvbuf(f, NULL, mode[op], 
+  luaL_optinteger(L,3,0)) == 0, NULL);

DB