1  /* Linux implementation of pwritev2 (LFS version).
       2     Copyright (C) 2017-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <sys/uio.h>
      20  #include <sysdep-cancel.h>
      21  
      22  ssize_t
      23  pwritev64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
      24  	     int flags)
      25  {
      26    ssize_t result = SYSCALL_CANCEL (pwritev2, fd, vector, count,
      27  				   LO_HI_LONG (offset), flags);
      28    if (result >= 0 || errno != ENOSYS)
      29      return result;
      30  
      31    /* Trying to emulate the pwritev2 syscall flags is troublesome:
      32  
      33       * We can not temporary change the file state of the O_DSYNC and O_SYNC
      34         flags to emulate RWF_{D}SYNC (attempts to change the state of using
      35         fcntl are silently ignored).
      36  
      37       * IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal
      38         semantic not provided by any other flag (O_NONBLOCK for instance).  */
      39  
      40    if (flags != 0)
      41      {
      42        __set_errno (ENOTSUP);
      43        return -1;
      44      }
      45    if (offset == -1)
      46      return __writev (fd, vector, count);
      47    else
      48      return pwritev64 (fd, vector, count, offset);
      49  }
      50  
      51  #ifdef __OFF_T_MATCHES_OFF64_T
      52  strong_alias (pwritev64v2, pwritev2)
      53  #endif