** Bug fixes
+ dd's oflag=direct option now works even when the size of the input
+ is not a multiple of e.g., 512 bytes.
+
install runs faster again with SELinux enabled
[introduced in coreutils-7.0]
@opindex direct
@cindex direct I/O
Use direct I/O for data, avoiding the buffer cache.
+Note that the kernel may impose restrictions on read or write buffer sizes.
+For example, with an ext4 destination file system and a linux-based kernel,
+using @samp{oflag=direct} will cause writes to fail with @code{EINVAL} if the
+output buffer size is not a multiple of 512.
@item directory
@opindex directory
{
size_t total_written = 0;
+ if ((output_flags & O_DIRECT) && size < output_blocksize)
+ {
+ int old_flags = fcntl (STDOUT_FILENO, F_GETFL);
+ if (fcntl (STDOUT_FILENO, F_SETFL, old_flags & ~O_DIRECT) != 0)
+ error (0, errno, _("failed to turn off O_DIRECT: %s"),
+ quote (output_file));
+ }
+
while (total_written < size)
{
ssize_t nwritten;
|| S_ISDIR (stdout_stat.st_mode)
|| S_TYPEISSHM (&stdout_stat))
error (EXIT_FAILURE, ftruncate_errno,
- _("truncating at %"PRIuMAX" bytes in output file %s"),
+ _("failed to truncate to %"PRIuMAX" bytes in output file %s"),
size, quote (output_file));
}
}
cp/src-base-dot \
cp/symlink-slash \
cp/thru-dangling \
+ dd/direct \
dd/misc \
dd/not-rewound \
dd/reblock \
--- /dev/null
+#!/bin/sh
+# ensure that dd's oflag=direct works
+
+# Copyright (C) 2009 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 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/>.
+
+if test "$VERBOSE" = yes; then
+ set -x
+ dd --version
+fi
+
+. $srcdir/test-lib.sh
+
+truncate -s 8192 in || framework_failure
+dd if=in oflag=direct of=out 2> /dev/null \
+ || skip_test_ 'this file system lacks support for O_DIRECT'
+
+truncate -s 511 short || framework_failure
+truncate -s 8191 m1 || framework_failure
+truncate -s 8193 p1 || framework_failure
+
+fail=0
+for i in short m1 p1; do
+ rm -f out
+ dd if=$i oflag=direct of=out || fail=1
+done
+
+Exit $fail