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
close(2) can return errors from previous operations which should not be ignored.
PR: 229616
Submitted by: Thomas Hurst
Reported by: Thomas Hurst
Reviewed by: mmacy@
Obtained from: Ryan Moeller
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21376
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
Notable changes from what landed in r337505:
- sigalarm handler isn't setup unless we're actually using it
- Humanized versions of the amount of data transferred in the progress
update
Submitted by: imp
Reviewed by: kevans
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D16642
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
dd is a bootstrap tool and that header isn't installed as part of the
bootstrap environment for previous releases (eg freebsd-10.)
We'll figure it out in post and then re-commit it.
X1000 systems on chips.
Imgtec CI20 and Ingenic CANNA boards supported.
Submitted by: Alexander Kabaev <kan@FreeBSD.org>
Reviewed by: Ruslan Bukin <br@FreeBSD.org>
Sponsored by: DARPA, AFRL
(when they actually get committed, that is), and might also come in handy
in other situations.
Reviewed by: wblock@ (man page)
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
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
conv=sparse.
This change fixes two separate issues observed when the last output
block is all zeroes, and conv=sparse is in use. In this case, care
must be taken to roll back the last seek and write the entire last zero
block at the original offset where it should have occurred: when the
destination file is a block device, it is not possible to roll back
by just one character as the write would then not be properly aligned.
Furthermore, the buffer used to write this last all-zeroes block
needs to be properly zeroed-out. This was not the case previously,
resulting in a junk data byte appearing instead of a zero in the
output stream.
PR: bin/189174
PR: bin/189284
Reviewed by: kib
MFC after: 2 weeks
gettimeofday returns the system clock, which may jump forward or back,
especially if NTP is in use. If the time jumps backwards, then dd will see
negative elapsed time, round it up to 1usec, and print an absurdly fast
transfer rate.
The solution is to use clock_gettime(2) with CLOCK_MONOTONIC_PRECISE as the
clock_id. That clock advances steadily, regardless of changes to the system
clock.
Reviewed by: delphij
MFC after: 3 days
Sponsored by: Spectra Logic
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
If the bs= expr operand is specified and no conversions other than sync,
noerror, or notrunc are requested, the data returned from each input
block shall be written as a separate output block.
In particular, when both bs=size and conv=sparce were specified, the
resulted file was fully filled, instead of sparce.
PR: standards/177742
Submitted by: Matthew Rezny <mrezny@hexaneinc.com>
MFC after: 2 weeks
Introduce an explicit close of the output descriptor so that work done
on close is accounted for in the summary output triggered at exit
(implicit close()s occur after atexit() hooks).
This is useful because some devices such as cfi(4) may perform
signficant work after a close occurs (e.g. erasing and rewriting a
block of flash).
This structure is not part of POSIX. According to POSIX, gettimeofday()
has the following prototype:
int gettimeofday(struct timeval *restrict tp, void *restrict tzp);
Also, POSIX states that gettimeofday() shall return 0 (as long as tzp is
not used). Remove dead error handling code. Also use NULL for a
nul-pointer instead of integer 0.
While there, change all pieces of code that only use tv_sec to use
time(3), as this provides less overhead.
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.
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
they already are.
Approved by: arch@, new style(9)