kind=defined
names===,eql?
visibility=public

--- eql?(other)     -> bool
--- ==(other)       -> bool

ポインタの指すアドレスが同一かどうかを判定します。

例:

 require 'dl' 
 
 s = 'abc'
 cptr  = DL::CPtr[s]
 cptr0 = DL::CPtr[s]
 cptr1 = cptr + 1
 
 p cptr == cptr1     #=> false
 p cptr == cptr0     #=> true

