43 lines
1.6 KiB
C
43 lines
1.6 KiB
C
/* System call limits
|
|
|
|
Copyright 2018-2023 Free Software Foundation, Inc.
|
|
|
|
This file 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.
|
|
|
|
This file 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 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
|