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/* System call limits

   Copyright 2018 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, see <>.  */

#ifndef _SYS_LIMITS_H
#define _SYS_LIMITS_H

#include <limits.h>

/* Maximum number of bytes to read or write in a single system call.
   This can be useful for system calls like sendfile on GNU/Linux,
   which do not handle more than MAX_RW_COUNT bytes correctly.
   The Linux kernel MAX_RW_COUNT is at least INT_MAX >> 20 << 20,
   where the 20 comes from the Hexagon port with 1 MiB pages; use that
   as an approximation, as the exact value may not be available to us.

   Using this also works around a serious Linux bug before 2.6.16; see

   Using this also works around a Tru64 5.1 bug, where attempting
   to read INT_MAX bytes fails with errno == EINVAL.  See

   Using this is likely to work around similar bugs in other operating
   systems.  */

enum { SYS_BUFSIZE_MAX = INT_MAX >> 20 << 20 };