.Fa start_size
bytes, and specifying
.Fa flags
-that alter the standard behavior of the zone.
The returned malloc zone can be used to provide custom allocation and
deallocation behavior, and to retrieve additional information about the
allocations in that zone.
+At present there are no client settable flag values recognized by malloc_create_zone(),
+the flags argument should always be passed as zero.
.Pp
The
.Fn malloc_destroy_zone