dar_xform - disk archive "re-slicer"
dar_xform [options] [<path>/]source [<path>/]destination
dar_xform changes the size of slices of an existing archive.
Source is the basename of the existing archive, destination is the
basename of the archive to be created. If source basename is "-", the
archive is read from standard input. If the destination basename is
"-", the archive is written to standard output and -s option is not
-h displays help usage.
-V displays version information.
-b make the terminal ring when user interaction is
required (like for example the creation of a new
slice when using the -p option)
-s <number> Size of the slices in bytes. If the number is
followed by k (or K), M, G, T or P the size is in
kilobytes, megabytes, gigabytes, terabytes or
petabytes respectively. Example: by default "20M"
means 20 megabytes it is the same as giving
20971520 as argument (see also -aSI and -abinary
options). If -s is not present the backup will be
written to a single slice whatever the size of the
backup may be (there is probably some filesystem
limitation, thus you might expect problems with
file size over 2 gigabytes, depending on your
-S <number> -S gives the size of the first slice which may be
chosen independently of the size of following
slices. This option needs -s and by default, the
size of the first slice is the same as the one of
the following slices.
-p [<integer>] pauses before writing to a new slice (this requires
-s). By default there is no pause, all slices are
output in the same directory, up to the end of the
backup or until the filesystem is full. In this
later case, the user is informed of the lack of
disk space and dar stops for user interaction. As
soon as some disk space is available, the user can
continue the backup. The optional integer that this
option can receive tells dar to only pause very ’n’
slice. Giving 3 for ’n’ will make dar pause only
after slices 3, 6, 9 and so on. If this integer is
not specified, the behavior is as if ’1’ was given
as argument which makes dar pause after each slice.
-n Do not allow overwriting of any slice.
-w Do not warn before overwriting slice. By default
(no -n and no -w) overwriting is allowed but a
warning is issued before proceeding.
-E <string> the string is a command-line to be launched between
the slices of the destination archive. See dar(1)
man page (same option) for more informations.
-F <string> the string is a command-line to be launched between
the slices of the source archive. See dar(1) man
page (same option) for more informations.
-aSI[-unit[s]] when using k M G T E Z Y prefixes to define a size,
use the SI meaning: multiple of 10^3 (a Mega is
-abinary[-unit[s]] when using k M G T E Z Y prefixes to define a size,
use the historical computer science meaning:
multiple of 2^10 (a Mega is 1,048,576).
-aSI and -abinary can be used several times, they affect all prefix
which follow even those found in file included by -B option up to the
next -a... occurrence. Note that if in a file included by -B option an
-abinary or -aSI is met, it affects all the following prefix even those
outside the included files (for example in the following "-B some.dcf
-s 1K" 1K may be equal to 1000 or 1024 depending on the presence of an
-aSI or -abinary in the file some.dcf. By default (before any
-aSI/binary argument has been reached), binary interpretation of suffix
is done (for compatibility with older versions).
-Q Do not display any message on stderr when not
launched from a terminal (for example when launched
from an at job or crontab). Remains that any
question to the user will be assumed a ’no’ answer,
which most of the time will abort the program.
-j when virtual memory is exhausted, as user to make
room before trying to continue. By default, when
memory is exhausted dar aborts.
Dar is not concerned by scrambling. It does not need to be aware of it
to be able to change the slice scheme. Thus, it is not able to scramble
a clear archive or unscramble an already scrambled archive.
dar_xform uses the same exit status as dar does, see dar(1) man page.
Any signal sent to dar_xform will abort the program immediately, there
is no way to have a proper termination before the end of the process
dar(1), dar_slave(1), dar_manager(1), dar_cp(1)