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-rw-r--r--sysdeps/posix/pwrite64.c59
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diff --git a/sysdeps/posix/pwrite64.c b/sysdeps/posix/pwrite64.c
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+++ b/sysdeps/posix/pwrite64.c
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+/* Write block to given position in file without changing file pointer.
+ POSIX version.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <errno.h>
+#include <unistd.h>
+
+ssize_t
+__pwrite64 (int fd, const void *buf, size_t nbyte, off64_t offset)
+{
+ /* Since we must not change the file pointer preserve the value so that
+ we can restore it later. */
+ int save_errno;
+ ssize_t result;
+ off64_t old_offset = lseek64 (fd, 0, SEEK_CUR);
+ if (old_offset == (off64_t) -1)
+ return -1;
+
+ /* Set to wanted position. */
+ if (lseek64 (fd, offset, SEEK_SET) == (off64_t) -1)
+ return -1;
+
+ /* Write out the data. */
+ result = write (fd, buf, nbyte);
+
+ /* Now we have to restore the position. If this fails we have to
+ return this as an error. But if the writing also failed we
+ return this error. */
+ save_errno = errno;
+ if (lseek64 (fd, old_offset, SEEK_SET) == (off64_t) -1)
+ {
+ if (result == -1)
+ __set_errno (save_errno);
+ return -1;
+ }
+ __set_errno (save_errno);
+
+ return result;
+}
+#ifndef __pwrite64
+weak_alias (__pwrite64, pwrite64)
+#endif