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m---------gnulib0
-rw-r--r--gnulib/lib/pwrite.c64
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diff --git a/gnulib b/gnulib
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-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/lib/pwrite.c b/gnulib/lib/pwrite.c
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+++ b/gnulib/lib/pwrite.c
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+/* Write block to given position in file without changing file pointer.
+ POSIX version.
+ Copyright (C) 1997-1999, 2002, 2011 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ 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 of the License, 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 <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <unistd.h>
+
+#include <errno.h>
+
+#define __libc_lseek(f,o,w) lseek (f, o, w)
+#define __set_errno(Val) errno = (Val)
+#define __libc_write(f,b,n) write (f, b, n)
+
+/* Note: This implementation of pwrite is not multithread-safe. */
+
+ssize_t
+pwrite (int fd, const void *buf, size_t nbyte, off_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;
+ off_t old_offset = __libc_lseek (fd, 0, SEEK_CUR);
+ if (old_offset == (off_t) -1)
+ return -1;
+
+ /* Set to wanted position. */
+ if (__libc_lseek (fd, offset, SEEK_SET) == (off_t) -1)
+ return -1;
+
+ /* Write out the data. */
+ result = __libc_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 (__libc_lseek (fd, old_offset, SEEK_SET) == (off_t) -1)
+ {
+ if (result == -1)
+ __set_errno (save_errno);
+ return -1;
+ }
+ __set_errno (save_errno);
+
+ return result;
+}