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+/* System call limits
+
+ Copyright 2018-2020 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
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ 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 <https://www.gnu.org/licenses/>. */
+
+#ifndef _GL_SYS_LIMITS_H
+#define _GL_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
+ <https://bugzilla.redhat.com/show_bug.cgi?id=612839>.
+
+ Using this also works around a Tru64 5.1 bug, where attempting
+ to read INT_MAX bytes fails with errno == EINVAL. See
+ <https://lists.gnu.org/r/bug-gnu-utils/2002-04/msg00010.html>.
+
+ Using this is likely to work around similar bugs in other operating
+ systems. */
+
+enum { SYS_BUFSIZE_MAX = INT_MAX >> 20 << 20 };
+
+#endif