pv
(1)
Name
pv - monitor the progress of data through a pipe
Synopsis
pv [OPTION] [FILE]...
pv [-h|-V]
Description
User Manuals pv(1)
NAME
pv - monitor the progress of data through a pipe
SYNOPSIS
pv [OPTION] [FILE]...
pv [-h|-V]
DESCRIPTION
pv allows a user to see the progress of data through a pipe-
line, by giving information such as time elapsed, percentage
completed (with progress bar), current throughput rate,
total data transferred, and ETA.
To use it, insert it in a pipeline between two processes,
with the appropriate options. Its standard input will be
passed through to its standard output and progress will be
shown on standard error.
pv will copy each supplied FILE in turn to standard output
means standard input), or if no FILEs are specified just
standard input is copied. This is the same behaviour as
cat(1).
A simple example to watch how quickly a file is transferred
using nc(1):
pv file | nc -w 1
A similar example, transferring a file from another process
and passing the expected size to pv:
cat file | pv -s 12345
A more complicated example using numeric output to feed into
the dialog(1) program for a full-screen progress display:
(tar cf - . \
| pv -n -s $(du -sb . | awk '{print $1}') \
| gzip -9 > out.tgz) 2>&1 \
| dialog --gauge 'Progress' 7 70
Frequent use of this third form is not recommended as it may
cause the programmer to overheat.
OPTIONS
pv takes many options, which are divided into display
switches, output modifiers, and general options.
Linux Last change: December 2010 1
User Manuals pv(1)
DISPLAY SWITCHES
If no display switches are specified, pv behaves as if -p,
-t, -e, had been given (i.e. everything except average rate
is switched on). Otherwise, only those display types that
are explicitly switched on will be shown.
-p, --progress
Turn the progress bar on. If standard input is not a
file and no size was given (with the -s modifier), the
progress bar cannot indicate how close to completion
the transfer is, so it will just move left and right to
indicate that data is moving.
-t, --timer
Turn the timer on. This will display the total elapsed
time that pv has been running for.
-e, --eta
Turn the ETA timer on. This will attempt to guess,
based on previous transfer rates and the total data
size, how long it will be before completion. This
option will have no effect if the total data size can-
not be determined.
-r, --rate
Turn the rate counter on. This will display the cur-
rent rate of data transfer.
-a, --average-rate
Turn the average rate counter on. This will display
the average rate of data transfer so far.
-b, --bytes
Turn the total byte counter on. This will display the
total amount of data transferred so far.
-n, --numeric
Numeric output. Instead of giving a visual indication
of progress, pv will give an integer percentage, one
per line, on standard error, suitable for piping (via
convoluted redirection) into dialog(1). Note that -f
is not required if -n is being used.
-q, --quiet
No output. Useful if the -L option is being used on
its own to just limit the transfer rate of a pipe.
OUTPUT MODIFIERS
-W, --wait
Wait until the first byte has been transferred before
Linux Last change: December 2010 2
User Manuals pv(1)
showing any progress information or calculating any
ETAs. Useful if the program you are piping to or from
requires extra information before it starts, eg piping
data into gpg(1) or mcrypt(1) which require a
passphrase before data can be processed.
-s SIZE, --size SIZE
Assume the total amount of data to be transferred is
SIZE bytes when calculating percentages and ETAs. The
same suffixes of "k", "m" etc can be used as with -L.
-l, --line-mode
Instead of counting bytes, count lines (newline charac-
ters). The progress bar will only move when a new line
is found, and the value passed to the -s option will be
interpreted as a line count.
-i SEC, --interval SEC
Wait SEC seconds between updates. The default is to
update every second. Note that this can be a decimal
such as 0.1.
-w WIDTH, --width WIDTH
Assume the terminal is WIDTH characters wide, instead
of trying to work it out (or assuming 80 if it cannot
be guessed).
-H HEIGHT, --height HEIGHT
Assume the terminal is HEIGHT rows high, instead of
trying to work it out (or assuming 25 if it cannot be
guessed).
-N NAME, --name NAME
Prefix the output information with NAME. Useful in
conjunction with -c if you have a complicated pipeline
and you want to be able to tell different parts of it
apart.
-f, --force
Force output. Normally, pv will not output any visual
display if standard error is not a terminal. This
option forces it to do so.
-c, --cursor
Use cursor positioning escape sequences instead of just
using carriage returns. This is useful in conjunction
with -N (name) if you are using multiple pv invocations
in a single, long, pipeline.
Linux Last change: December 2010 3
User Manuals pv(1)
DATA TRANSFER MODIFIERS
-L RATE, --rate-limit RATE
Limit the transfer to a maximum of RATE bytes per sec-
ond. A suffix of "k", "m", "g", or "t" can be added to
denote kilobytes (*1024), megabytes, and so on.
-B BYTES, --buffer-size BYTES
Use a transfer buffer size of BYTES bytes. A suffix of
"k", "m", "g", or "t" can be added to denote kilobytes
(*1024), megabytes, and so on. The default buffer size
is the block size of the input file's filesystem multi-
plied by 32 (512kb max), or 400kb if the block size
cannot be determined.
-R PID, --remote PID
If PID is an instance of pv that is already running, -R
PID will cause that instance to act as though it had
been given this instance's command line instead. For
example, if pv -L 123k is running with process ID 9876,
then running pv -R 9876 -L 321k will cause it to start
using a rate limit of 321k instead of 123k. Note that
some options cannot be changed while running, such as
-c, -l, and -f.
GENERAL OPTIONS
-h, --help
Print a usage message on standard output and exit suc-
cessfully.
-V, --version
Print version information on standard output and exit
successfully.
EXIT STATUS
An exit status of 1 indicates a problem with the -R option.
Any other exit status is a bitmask of the following:
2 One or more files could not be accessed, stat(2)ed, or
opened.
4 An input file was the same as the output file.
8 Internal error with closing a file or moving to the
next file.
16 There was an error while transferring data from one or
Linux Last change: December 2010 4
User Manuals pv(1)
more input files.
32 A signal was caught that caused an early exit.
64 Memory allocation failed.
A zero exit status indicates no problems.
AUTHORS
Andrew Wood <[email protected]>
http://www.ivarch.com/
Kevin Coyner <[email protected]>
(Debian package maintainer)
Jakub Hrozek <[email protected]>
(Fedora package maintainer)
Cedric Delfosse <[email protected]>
(previous Debian package maintainer)
Eduardo Aguiar <[email protected]>
(provided Portuguese [Brazilian] translation)
Stephane Lacasse <[email protected]>
(provided French translation)
http://gorfou.ca/
Marcos Kreinacke <[email protected]>
(provided German translation)
Bartosz Fenski <[email protected]>
(provided Polish translation, along with Krystian Zubel)
http://skawina.eu.org/
Joshua Jensen
(reported RPM installation bug)
Boris Folgmann
(reported cursor handling bug)
http://www.folgmann.com/en/
Mathias Gumz
(reported NLS bug)
Daniel Roethlisberger
(submitted patch to use lockfiles for -c if terminal locking
fails)
Linux Last change: December 2010 5
User Manuals pv(1)
Adam Buchbinder
(lots of help with a Cygwin port of -c)
Mark Tomich
(suggested -B option)
http://metuchen.dyndns.org
Gert Menke
(reported bug when piping to dd with a large input buffer
size)
Ville Herva <[email protected]>
(informative bug report about rate limiting performance)
Elias Pipping
(patch to compile properly on Darwin 9; potential NULL deref
report)
Patrick Collison
(similar patch for OS X)
Boris Lohner
(reported problem that -L does not complain if given non-
numeric value)
Sebastian Kayser
(supplied testing for SIGPIPE, demonstrated internationali-
sation problem)
Laszlo Ersek
(reported shared memory leak on SIGINT with -c)
http://phptest11.atw.hu/
Phil Rutschman
(provided a patch for fully restoring terminal state on
exit)
http://bandgap.rsnsoft.com/
Henry Precheur
(reporting and suggestions for --rate-limit bug when rate is
under 10)
http://henry.precheur.org/
E. Rosten
(supplied patch for block buffering in line mode)
http://mi.eng.cam.ac.uk/~er258/
Kjetil Torgrim Homme
(reported compilation error with default CFLAGS on non-GCC
compilers)
Alexandre de Verteuil
Linux Last change: December 2010 6
User Manuals pv(1)
(reported bug in OS X build and supplied test environment to
fix in)
Martin Baum
(supplied patch to return nonzero exit status if terminated
by signal)
Sam Nelson
(supplied patch to fix trailing slash on DESTDIR)
http://www.siliconfuture.net/
Daniel Pape
(reported Cygwin installation problem due to DESTDIR)
Henry Gebhardt <[email protected]>
(supplied patches to improve SI prefixes and add --average-
rate)
Vladimir Kokarev
Alexander Leo
(reported that exit status did not reflect file errors)
BUGS
If you find any bugs, please contact the primary author,
either by email or by using the contact form on the web
site.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+-------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-------------------+
|Availability | shell/pipe-viewer |
+---------------+-------------------+
|Stability | Uncommitted |
+---------------+-------------------+
SEE ALSO
cat(1), dialog(1)
LICENSE
This is free software, distributed under the ARTISTIC 2.0
license.
Linux Last change: December 2010 7
User Manuals pv(1)
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://pipeviewer.googlecode.com/files/pv-1.2.0.tar.gz
Further information about this software can be found on the
open source community website at http://www.ivarch.com/pro-
grams/pv.shtml.
Linux Last change: December 2010 8