re-entrant

3 definitions found

re-entrant - Collaborative International Dictionary of English v.0.48 :

  Reentrant \Re*en"trant\ (-trant), a.
     Reentering; pointing or directed inwards; as, a reentrant
     angle.
     [1913 Webster]

re-entrant - WordNet (r) 2.1 (2005) :

  re-entrant
      adj 1: (of angles) pointing inward; "a polygon with re-entrant
             angles" [syn: re-entrant, reentrant] [ant: salient]

re-entrant - Free On-line Dictionary of Computing (26 May 2007) :

  re-entrant
  
     <programming> Used to describe code which can have multiple
     simultaneous, interleaved, or nested invocations which will
     not interfere with each other.  This is important for
     parallel processing, recursive functions or subroutines,
     and interrupt handling.
  
     It is usually easy to arrange for multiple invocations
     (e.g. calls to a subroutine) to share one copy of the code and
     any read-only data but, for the code to be re-entrant, each
     invocation must use its own copy of any modifiable data (or
     synchronised access to shared data).  This is most often
     achieved using a stack and allocating local variables in a
     new stack frame for each invocation.  Alternatively, the
     caller may pass in a pointer to a block of memory which that
     invocation can use (usually for outputting the result) or the
     code may allocate some memory on a heap, especially if the
     data must survive after the routine returns.
  
     Re-entrant code is often found in system software, such as
     operating systems and teleprocessing monitors.  It is also
     a crucial component of multithreaded programs where the term
     "thread-safe" is often used instead of "re-entrant".
  
     (1996-12-21)