text: /* Copyright (C) 1991, 94, 95, 97, 98, 2000 Free Software Foundation, Inc.
     This file is part of the GNU C Library.
  
     The GNU C Library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
     License as published by the Free Software Foundation; either
     version 2.1 of the License, or (at your option) any later version.
  
     The GNU C Library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public
     License along with the GNU C Library; if not, write to the Free
     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
     02111-1307 USA.  */
  
  #include <errno.h>
  #include <hurd.h>
  #include <unistd.h>
  
  /* Extend the process's data space by INCREMENT.
     If INCREMENT is negative, shrink data space by - INCREMENT.
     Return the address of the start of the new data space, or -1 for errors.  */
  void *
  __sbrk (intptr_t increment)
  {
    void *result;
  
    HURD_CRITICAL_BEGIN;
    __mutex_lock (&_hurd_brk_lock);
    result = (void *) _hurd_brk;
    if (increment != 0 && _hurd_set_brk (_hurd_brk + increment) < 0)
      result = (void *) -1;
    __mutex_unlock (&_hurd_brk_lock);
    HURD_CRITICAL_END;
  
    return result;
  }
  
  weak_alias (__sbrk, sbrk)
  