Normally, count=n means read(2) will be called n times on the input to dd. If
the read() returns short, as may happen when reading from a pipe, fewer bytes
will be copied from the input. With conv=sync the buffer is padded with zeros
to fill the rest of the block.
iflag=fullblock causes dd to continue reading until the block is full, so that
count=n means n full blocks are copied. This flag is compatible with illumos
and GNU dd and is used in the ZFS test suite.
Submitted by: Ryan Moeller
Reviewed by: manpages, mmacy@
MFC after: 1 week
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D21441
Sets the O_FSYNC flag on the output file. oflag=fsync and oflag=sync are
synonyms just as O_FSYNC and O_SYNC are synonyms. This functionality is
intended to improve portability of dd commands in the ZFS test suite.
Submitted by: Ryan Moeller
Reviewed by: manpages, mmacy@
MFC after: 1 week
Sponsored by: iXsytems, Inc.
Differential Revision: https://reviews.freebsd.org/D21422
The fdatasync flag performs an fdatasync(2) on the output file before closing it.
This will be useful for the ZFS test suite.
Submitted by: Ryan Moeller
Reviewed by: manpages, mmacy@
MFC after: 1 week
Sponsored by: iXSystems, Inc.
Differential Revision: https://reviews.freebsd.org/D21373
The fsync flag performs an fsync(2) on the output file before closing it.
This will be useful for the ZFS test suite.
Submitted by: ryan@ixsystems.com
Reviewed by: jilles@, imp@
MFC after: 1 week
Sponsored by: iXsystems, Inc.
with macro based around memcmp(). The latter is expected to be some
8 times faster on a modern 64-bit architectures.
In practice, throughput of doing conv=sparse from /dev/zero to /dev/null
went up some 5-fold here from 1.9GB/sec to 9.7GB/sec with this change
(bs=128k).
MFC after: 2 weeks
This reports the current status on a single line every second, mirroring
similar functionality in GNU dd, and carefully interacts with SIGINFO.
PR: 229615
Submitted by: Thomas Hurst <tom@hur.st> (modified for style(9) nits by me)
MFC after: 1 week
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
dd(1) casts many of its numeric arguments from uintmax_t to intmax_t and
back again to detect whether or not the original arguments were negative.
This is not correct, and causes problems with boundary cases, for example
when count is SSIZE_MAX-1.
PR: 191263
Submitted by: will@worrbase.com
Reviewed by: pi, asomers
MFC after: 3 weeks
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.
Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96
The intent of the previous code in that case was to force
an explicit write, but the implementation was incorrect, and
as a result the write was never performed. This new implementation
instead uses ftruncate(2) to extend the file with a trailing hole.
Also introduce regression tests for these cases.
PR: 189284
(original PR whose fix introduced this bug)
PR: 207092
Differential Revision: D5248
Reviewed by: sobomax,kib
MFC after: 2 weeks
dd(1) casts many of its numeric arguments from uintmax_t to intmax_t
and back again to detect whether or not the original arguments were
negative. This caused wrong behaviour in some boundary cases:
$ dd if=/dev/zero of=/dev/null count=18446744073709551615
dd: count cannot be negative
After the fix:
$ dd if=/dev/zero of=/dev/null count=18446744073709551615
dd: count: Result too large
PR: 191263
Submitted by: will@worrbase.com
Approved by: cognet@
* Don't use sysexits.h. Just exit 1 on error and 0 otherwise.
* Don't sacrifice precision by converting the output of clock_gettime() to a
double and then comparing the results. Instead, subtract the values of
the two clock_gettime() calls, then convert to double.
* Don't use CLOCK_MONOTONIC_PRECISE. It's an unportable synonym for
CLOCK_MONOTONIC.
* Use more appropriate names for some local variables.
* In the summary message, round elapsed time to the nearest microsecond.
Reported by: bde, jilles
MFC after: 3 days
X-MFC-With: 265472
borrowed where syntax status=noxfer means no transfer statistics
and status=none means no status information at all.
This feature is useful because the statistics information can
sometimes be annoying, and redirecting stderr to /dev/null would
mean error messages also gets silenced.
Obtained from: OpenBSD
MFC after: 2 weeks
to specify an alternative padding character when using a conversion
mode, or when using noerror with sync and an input error occurs. This
facilities reading old and error-prone media by allowing the user to
more effectively mark error blocks in the output stream.
BDEification process of dd(1). Most of the changes are from BDE's archive.
Support for negative offsets is gone again, but the case where you
lseek() onto byte -1 of something from a negative offset using seek/skip
is fixed; if you end up on -1, you won't get a false positive lseek failure.
The biggest changes are to data types (more size_t, for instance) and
argument parsing. skip/seek on /dev/{,k}mem now occurs (instead of "read
until you reach the offset") due to mem devices now being D_DISK. Some
const things are now correctly declared as such, and the "case table"
building is better. The only thing that seems to be left to make dd(1)
everything TOG wants it to be is l10n.
request of Bruce. More changes may follow later. 'g' multiplier has
been added (i.e. dd seek=5g if=bigfile.) Some minor corrections were made
as well.
Noticed by: bde
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
and he's right ... I forgot about this floating point stuff you can
use in user-land :-)
Increase precision of duration to microseconds.
No heuristics to avoid overflow in calculation needed - just depend
on DBL_MAX being a bit larger than LONG_MAX.
Use double instead of `struct timeval' in dd.h so that everything
doesn't have to include <sys/time.h>.
Fixed style bugs in recent and old FreeBSD changes.
Reviewed by: phk
Submitted by: bde
