anchor.diff:  
   (include "errno.h")
   
  -(declaim (inline errno))
  +(declaim (inline errno %set-errno))
  +
   (defwrapper* ("iolib_get_errno" errno) :int
     ()
     "return errno;")
   
  -(declaim (inline %set-errno))
   (defwrapper* ("iolib_set_errno" %set-errno) :int
     ((value :int))
  -  "errno = value;"
  -  "return errno;")
  +  "errno = value; return errno;")
    
   
  
positive.code: (include "sys/types.h" "dirent.h")
  
  (declaim (inline dirfd))
  (defwrapper (dirfd "dirfd") :int
    (dirp ("DIR*" :pointer)))
  
negative.code: (include "stdlib.h") ; needed on FreeBSD to define NULL
  (include "sys/socket.h")
  
  (declaim (inline cmsg.space cmsg.len cmsg.firsthdr cmsg.data))
  
  (defwrapper ("CMSG_SPACE" cmsg.space) :unsigned-int
    (data-size :unsigned-int))
  
  (defwrapper ("CMSG_LEN" cmsg.len) :unsigned-int
    (data-size :unsigned-int))
  
  (defwrapper ("CMSG_FIRSTHDR" cmsg.firsthdr) :pointer
    (msg ("struct msghdr*" :pointer)))
  
  (defwrapper ("CMSG_DATA" cmsg.data) :pointer
    (cmsg ("struct cmsghdr*" :pointer)))
  