anchor.diff:  ;;;-------------------------------------------------------------------------
   
   (defsyscall* (%%sys-open "open") :int
  -  (pathname filename-designator)
  -  (flags    :int)
  -  (mode     mode-t))
  +  (path  filename-designator)
  +  (flags :int)
  +  (mode  mode-t))
   
   (defvar *default-open-mode* #o666)
   
  -(defentrypoint %sys-open (pathname flags &optional (mode *default-open-mode*))
  -  (%%sys-open pathname flags mode))
  +(defentrypoint %sys-open (path flags &optional (mode *default-open-mode*))
  +  "Open a file descriptor for PATH using FLAGS and permissions MODE
  +\(default value is *DEFAULT-OPEN-MODE* - #o666)."
  +  (%%sys-open path flags mode))
   
   (defsyscall* (%sys-creat "creat") :int
  -  (pathname filename-designator)
  -  (mode     mode-t))
  +  "Create file PATH with permissions MODE and return the new FD."
  +  (path filename-designator)
  +  (mode mode-t))
   
   (defsyscall (%%sys-pipe "pipe") :int
     (filedes :pointer))
  
positive.code: (defcvar ("environ" :read-only t) (:pointer :string))
  
  (defsyscall (%sys-getenv "getenv") :string
    "Returns the value of an environment variable"
    (name :string))
  
  (defsyscall (%sys-setenv "setenv") :int
    "Changes the value of an environment variable"
    (name      :string)
    (value     :string)
    (overwrite bool-designator))
  
  (defsyscall (%sys-unsetenv "unsetenv") :int
    "Removes the binding of an environment variable"
    (name :string))
  
  
negative.code: ;;;-------------------------------------------------------------------------
  
  (defentrypoint (setf %sys-errno) (value)
    "Set errno value."
    (%%sys-set-errno value))
  
  (defsyscall (%%sys-strerror-r (#+linux "__xpg_strerror_r" "strerror_r"))
  