uio_lim.h 1.4 KB

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  1. /* Implementation limits related to sys/uio.h - Linux version.
  2. Copyright (C) 2017-2021 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <https://www.gnu.org/licenses/>. */
  15. #ifndef _BITS_UIO_LIM_H
  16. #define _BITS_UIO_LIM_H 1
  17. /* Maximum length of the 'struct iovec' array in a single call to
  18. readv or writev.
  19. This macro has different values in different kernel versions. The
  20. latest versions of the kernel use 1024 and this is good choice. Since
  21. the C library implementation of readv/writev is able to emulate the
  22. functionality even if the currently running kernel does not support
  23. this large value the readv/writev call will not fail because of this. */
  24. #define __IOV_MAX 1024
  25. #endif