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52bd938169
This patch adds support of preadv2 and pwritev2 which are similar to preadv/pwritev but with an extra flag argument. As for preadv/pwritev both interfaces are added a non-standard GNU API. For default 'posix' implementation trying to emulate the Linux supported flags is troublesome: * We can not temporary change the file state of the O_DSYNC and O_SYNC flags to emulate RWF_{D}SYNC (attempts to change the state of using fcntl are silently ignored). * IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal semantic not provided by any other flag (O_NONBLOCK for instance). So default sysdeps/posix implementations fails with EOPNOTSUPP for any non supported flag (which are none currently) calls generic preadv/pwritev. Basically this implementation supports only preadv2 called as preadv (with flags sets to 0). The Linux one uses the preadv2/pwritev2 syscall if defined, otherwise it call preadv/writev. Instead of using the previous __ASSUME_* to unconditionally issue the syscall (and avoid building the fallback routine), it call pread/write if the preadv2/pwritev2 syscalls fails. The idea is just avoid adding another __ASSUME_* and checking each architecture on every kernel bump and simplify code conditionals. Checked on x86_64-linux-gnu and on i686-linux-gnu and a check with run-built-tests=no on aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu, mips{64,64n32}-linux-gnu, nios2-linux-gnu, powerpc{64,64le}-linux-gnu, s390{x}-linux-gnu, sparc{64,v9}-linux-gnu, tile{gx,pro}-linux-gnu, and sh4-linux-gnu (all using gcc 6.3). * NEWS: Add note about pwritev2 and preadv2 inclusion. * misc/Makefile (routines): Add preadv2, preadv64v2, pwritev2, and pwritev64v2. (tests): Add tst-preadvwritev2 and tst-preadvwritev64v2. * misc/Versions (GLIBC_2.26): Add preadv2, preadv64v2, pwritev2, and pwritev64v2. * misc/preadv2.c: New file. * misc/preadv64v2.c: Likewise. * misc/pwritev2.c: Likewise. * misc/pwritev64v2.c: Likewise. * misc/tst-preadvwritev2.c: Likewise. * misc/tst-preadvwritev64v2.c: Likewise. * manual/llio.texi: Add preadv2 and pwritev2 documentation. * misc/sys/uio.h [__USE_GNU && !__USE_FILE_OFFSET64] (preadv2): New prototype. [__USE_GNU && !__USE_FILE_OFFSET64] (pwritev2): Likewise. [__USE_GNU && __USE_FILE_OFFSET64] (preadv64v2): Likewise. [__USE_GNU && __USE_FILE_OFFSET64] (pwritev64v2): Likewise. * misc/tst-preadvwritev-common.c (PREADV): Define if not defined. (PWRITEV): Likewise. (do_test_with_offset): Use PREADV and PWRITEV macros and check for ENOSYS. * nptl/tst-cancel4.c (tf_pwritev2): New test. (tf_preadv2): Likewise. (tf_fsync): Add tf_pwritev2 and tf_preadv2. * sysdeps/posix/preadv2.c: Likewise. * sysdeps/posix/preadv64v2.c: Likewise. * sysdeps/posix/pwritev2.c: Likewise. * sysdeps/posix/pwritev64v2.c: Likewise. * sysdeps/unix/sysv/linux/kernel-features.h: Add comment for syscall support in kernel. * sysdeps/unix/sysv/linux/preadv2.c: Likewise. * sysdeps/unix/sysv/linux/preadv64v2.c: Likewise. * sysdeps/unix/sysv/linux/pwritev2.c: Likewise. * sysdeps/unix/sysv/linux/pwritev64v2.c: Likewise. * sysdeps/unix/sysv/linux/preadv.c (preadv): Add libc_hidden_def. * sysdeps/unix/sysv/linux/preadv64.c (preadv64): Likewise. * sysdeps/unix/sysv/linux/pwritev.c (pwritev): Likewise. * sysdeps/unix/sysv/linux/pwritev64.c (pwritev64): Likewise. * sysdeps/unix/sysv/linux/bits/uio.h: Add supported preadv2/pwritev2 support flags on Linux. * sysdeps/unix/sysv/linux/aarch64/libc.abilist (GLIBC_2.26): Add preadv2, preadv64v2, pwritev2, pwritev64v2. * sysdeps/unix/sysv/linux/alpha/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/arm/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/hppa/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/i386/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/ia64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/microblaze/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/nios2/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/sh/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/sysv/linux/tile/tilegx/tilegx32/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/sysv/linux/tile/tilegx/tilegx64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libc.abilist (GLIBC_2.26): Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist (GLIBC_2.26): Likewise.
164 lines
5.9 KiB
C
164 lines
5.9 KiB
C
/* Copyright (C) 1991-2017 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#ifndef _SYS_UIO_H
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#define _SYS_UIO_H 1
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#include <features.h>
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#include <sys/types.h>
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__BEGIN_DECLS
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/* This file defines `struct iovec'. */
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#include <bits/uio.h>
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/* Read data from file descriptor FD, and put the result in the
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buffers described by IOVEC, which is a vector of COUNT 'struct iovec's.
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The buffers are filled in the order specified.
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Operates just like 'read' (see <unistd.h>) except that data are
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put in IOVEC instead of a contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t readv (int __fd, const struct iovec *__iovec, int __count)
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__wur;
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/* Write data pointed by the buffers described by IOVEC, which
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is a vector of COUNT 'struct iovec's, to file descriptor FD.
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The data is written in the order specified.
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Operates just like 'write' (see <unistd.h>) except that the data
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are taken from IOVEC instead of a contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t writev (int __fd, const struct iovec *__iovec, int __count)
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__wur;
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#ifdef __USE_MISC
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# ifndef __USE_FILE_OFFSET64
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/* Read data from file descriptor FD at the given position OFFSET
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without change the file pointer, and put the result in the buffers
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described by IOVEC, which is a vector of COUNT 'struct iovec's.
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The buffers are filled in the order specified. Operates just like
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'pread' (see <unistd.h>) except that data are put in IOVEC instead
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of a contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t preadv (int __fd, const struct iovec *__iovec, int __count,
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__off_t __offset) __wur;
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/* Write data pointed by the buffers described by IOVEC, which is a
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vector of COUNT 'struct iovec's, to file descriptor FD at the given
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position OFFSET without change the file pointer. The data is
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written in the order specified. Operates just like 'pwrite' (see
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<unistd.h>) except that the data are taken from IOVEC instead of a
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contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t pwritev (int __fd, const struct iovec *__iovec, int __count,
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__off_t __offset) __wur;
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# else
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# ifdef __REDIRECT
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extern ssize_t __REDIRECT (preadv, (int __fd, const struct iovec *__iovec,
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int __count, __off64_t __offset),
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preadv64) __wur;
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extern ssize_t __REDIRECT (pwritev, (int __fd, const struct iovec *__iovec,
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int __count, __off64_t __offset),
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pwritev64) __wur;
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# else
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# define preadv preadv64
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# define pwritev pwritev64
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# endif
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# endif
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# ifdef __USE_LARGEFILE64
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/* Read data from file descriptor FD at the given position OFFSET
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without change the file pointer, and put the result in the buffers
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described by IOVEC, which is a vector of COUNT 'struct iovec's.
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The buffers are filled in the order specified. Operates just like
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'pread' (see <unistd.h>) except that data are put in IOVEC instead
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of a contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t preadv64 (int __fd, const struct iovec *__iovec, int __count,
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__off64_t __offset) __wur;
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/* Write data pointed by the buffers described by IOVEC, which is a
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vector of COUNT 'struct iovec's, to file descriptor FD at the given
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position OFFSET without change the file pointer. The data is
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written in the order specified. Operates just like 'pwrite' (see
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<unistd.h>) except that the data are taken from IOVEC instead of a
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contiguous buffer.
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This function is a cancellation point and therefore not marked with
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__THROW. */
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extern ssize_t pwritev64 (int __fd, const struct iovec *__iovec, int __count,
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__off64_t __offset) __wur;
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# endif
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#endif /* Use misc. */
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#ifdef __USE_GNU
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# ifndef __USE_FILE_OFFSET64
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/* Same as preadv but with an additional flag argumenti defined at uio.h. */
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extern ssize_t preadv2 (int __fp, const struct iovec *__iovec, int __count,
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__off_t __offset, int ___flags) __wur;
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/* Same as preadv but with an additional flag argument defined at uio.h. */
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extern ssize_t pwritev2 (int __fd, const struct iovec *__iodev, int __count,
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__off_t __offset, int __flags) __wur;
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# else
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# ifdef __REDIRECT
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extern ssize_t __REDIRECT (pwritev2, (int __fd, const struct iovec *__iovec,
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int __count, __off64_t __offset,
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int __flags),
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pwritev64v2) __wur;
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extern ssize_t __REDIRECT (preadv2, (int __fd, const struct iovec *__iovec,
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int __count, __off64_t __offset,
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int __flags),
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preadv64v2) __wur;
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# else
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# define preadv2 preadv64v2
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# define pwritev2 pwritev64v2
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# endif
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# endif
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# ifdef __USE_LARGEFILE64
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/* Same as preadv but with an additional flag argumenti defined at uio.h. */
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extern ssize_t preadv64v2 (int __fp, const struct iovec *__iovec,
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int __count, __off64_t __offset,
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int ___flags) __wur;
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/* Same as preadv but with an additional flag argument defined at uio.h. */
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extern ssize_t pwritev64v2 (int __fd, const struct iovec *__iodev,
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int __count, __off64_t __offset,
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int __flags) __wur;
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# endif
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#endif /* Use GNU. */
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__END_DECLS
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#endif /* sys/uio.h */
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