[ruby-talk:00528] Single char conventions in Ruby's core?

Hi,

some of the functions/variables/datatypes in the ruby core have one
character in its name which is used, I assume, to indicate the kind
of it.

To understand the naming scheme behind it I want to know, what they
mean?

In the table below, I have added all chars I have already found, an
example of a function name, and my guess, what it means.

Char	Fn Name				Guess
---------------------------------------------------------
_s_	rb_ary_s_new			Singleton methods
_f_	rb_f_open			Global function
_r_	reloc_r_rightshift		?
_b_	syserr_list_b_general		?
_d_	old_d_vars			?

Can somebody please enlight me?

Thanks in advance,
Cle.