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/* This header file provides the reentrancy.  */

/* The reentrant system calls here serve two purposes:

   1) Provide reentrant versions of the system calls the ANSI C library
      requires.
   2) Provide these system calls in a namespace clean way.

   It is intended that *all* system calls that the ANSI C library needs
   be declared here.  It documents them all in one place.  All library access
   to the system is via some form of these functions.

   There are three ways a target may provide the needed syscalls.

   1) Define the reentrant versions of the syscalls directly.
      (eg: _open_r, _close_r, etc.).  Please keep the namespace clean.
      When you do this, set "syscall_dir" to "syscalls" and add
      -DREENTRANT_SYSCALLS_PROVIDED to newlib_cflags in configure.host.

   2) Define namespace clean versions of the system calls by prefixing
      them with '_' (eg: _open, _close, etc.).  Technically, there won't be
      true reentrancy at the syscall level, but the library will be namespace
      clean.
      When you do this, set "syscall_dir" to "syscalls" in configure.host.

   3) Define or otherwise provide the regular versions of the syscalls
      (eg: open, close, etc.).  The library won't be reentrant nor namespace
      clean, but at least it will work.
      When you do this, add -DMISSING_SYSCALL_NAMES to newlib_cflags in
      configure.host.

   Stubs of the reentrant versions of the syscalls exist in the libc/reent
   source directory and are used if REENTRANT_SYSCALLS_PROVIDED isn't defined.
   They use the native system calls: _open, _close, etc. if they're available
   (MISSING_SYSCALL_NAMES is *not* defined), otherwise open, close, etc.
   (MISSING_SYSCALL_NAMES *is* defined).  */

/* WARNING: All identifiers here must begin with an underscore.  This file is
   included by stdio.h and others and we therefore must only use identifiers
   in the namespace allotted to us.  */