News Rover RAR File Archive Support
News Rover Has Full Built-in Support
For RAR and PAR File Archives
What are RAR files?
RAR is a technique for compressing files and splitting them into multiple
pieces. It is widely used for posting large files because they
can be split into a set of reasonably sized segments. RAR files are similar to
ZIP files in the sense that they are compressed archives that must be
decompressed before you can access their contents. But RAR files are better
suited for compressing large files for Usenet posting because they are designed
to be split into multiple volumes.
Prior to RAR version 3.0, segments of RAR file sets had names ending with .rar,
.r00, .r01, .r02, etc., so a full file posting might have file names like
file.rar, file.r00, file.r01, etc. This format is still widely used.
Beginning with RAR version 3.0, a new naming convention was introduced that
adds two extensions to the file name; the first indicates the part number, and
the second is always ".rar". A typical file posting will have segments with
names such as file.part01.rar, file.part02.rar, file.part03.rar, etc. RAR
version 3.0 also introduced error recovery files with extensions of .rev, but
they are rarely used because PAR files are preferred.
What are PAR files?
Often, a set of PAR files is posted accompanying an RAR file set. PAR files
are parity recovery files that can be used to recovery missing or corrupted
segments of an RAR file set. The PAR files usually have names such as
file.part01.p01, file.part01.p02, etc.; you may also see file.part01.par,
but generally PAR files begin with .p01.
If all of the segments of a RAR file set are present and valid, you do not need
any of the PAR files. However, if any RAR segment is missing or corrupted, it
can be recovered by using a PAR file. It takes one PAR file to recover each
missing or damaged RAR segment. So if a file is posted with 10 PAR sections,
up to 10 damaged or missing RAR segments can be recovered. The only exception
to this is the PAR segment with the .par extension. The .par file is optional
and contains only information about what files are part of the set; it does not
contain recovery information. Usually, .par files are not used; they are never
needed. The actual recovery PAR files begin with .p01.
PAR files are independent of each other, so a missing or damaged PAR segment
will not affect the recovery as long as there are enough good PAR files to
replace missing and damaged RAR files.
Version 2 PAR files have extended file names of the form "name.volnn+mm.par2".
With PAR version 2, one PAR volume can be used to recover more than one
missing/damaged RAR volume, and the valid portion of a damaged RAR volume can
be used in the recovery process. News
Rover supports both version 1 and version 2 PAR files.
News Rover support for and RAR and
PAR files
News Rover is the ideal tool for
downloading RAR and PAR files from Usenet newsgroups. News Rover "understands" RAR file sets so
it can check and tell you if all of the segments are present or if there are
enough PAR segments to replace missing RAR segments. News Rover also has a
built-in decompressor for RAR files and a built-in PAR processor for recovering
missing RAR files, so you don't have to buy or use any other programs to
extract the contents of RAR archives. With News Rover, it is as easy to download RAR
files as JPG files. News Rover can
handle both version 1 and version 2 PAR files.
How to download and decompress RAR and PAR files
First, download the list of messages available in the group. You can get the
list of messages using a subscribed newsgroup, an Autoscan Interest Group or using the
File Attachment Locator features.
If the message list is downloaded from a subscribed newsgroup or a header-only
Autoscan Interest Group, News Rover automatically "threads" the
sections of the RAR/PAR file set. You will see one line in the message list
that represents the entire set of RAR sections -- possibly representing
throusands of individual messages. You can simply double-click the message
entry to start the RAR download.
If News Rover does not thread the RAR
sections into a single line, you can manually start the RAR download and
decompression. To do this, right click on the entry for any of the segments to
bring up a popup menu. Then left click on the entry in the popup menu "Download
and decompress RAR archive". News Rover
will then scan the message list and determine how many RAR and PAR segments are
part of this file set.
If all of the RAR segments are complete, News Rover will display a screen that looks
like this:
This screen tells you how many sections there are to the RAR archive and how
many individual messages (generally, each segment is made up of several
messages). It also tells you how many PAR sections are present. There are two
option checkboxes that you can select:
"Download PAR sections as well as RAR sections" -- If PAR sections are
available, this option will be enabled. If you check the box, News Rover will download the PAR sections
as well as the RAR sections. This is recommended because News Rover can use the PAR sections to
recover missing or damaged RAR sections.
"Combine and decompress when downloads finish" -- If you check this box, News Rover will begin automatically to
combine and decompress the segments of the RAR file set as soon as the
downloads finish. Note, if you stop News Rover and restart it, pending RAR
decompressions are forgotten and you will have to use the manual method
described below to combine and decompress the RAR files.
The screen has three buttons:
"Start downloading RAR archive now" -- Click this to cause News Rover to immediately begin downloading
all of the segments of the RAR archive.
"Mark RAR files for later download" -- Click this to cause News Rover to "tag" the files that are part
of the RAR archive for later download. A down-arrow icon will appear to the
left of each file that has been marked for download. When you are ready to
start the downloads, click the downward-pointing arrow icon on the News Rover toolbar.
"Delete all parts of this RAR archive" -- News Rover will delete all sections of the
RAR archive from the message list.
"Cancel" -- Click to exit the screen without downloading any files.
If any of the sections of the RAR file set are missing, News Rover will display a screen like this:
This screen tells you how many RAR sections there are and how many are missing.
It also tells you if there are enough PAR sections to recover the missing RAR
sections. It has the same set of options and buttons as the screen shown when
all of the sections are present.
If News Rover is able to successfully
decompress the RAR archive, the segments are deleted and a message is added to
the message list for the group with the full, decompressed file(s) from the
archive attached to it. You can then launch that attachment or save it just as
you would any other attachment that you downloaded. If the RAR archive cannot
be decompressed, News Rover leaves the
messages with the RAR segments.
Manually decompressing an RAR file set
The easiest way to decompress an RAR file set is to check the box labeled
"Combine and decompress when downloads finish" on the screen where you start
the download. However, if you have downloaded the RAR segments without
combining them, you can manually invoke the News Rover RAR decompressor. To do this,
right click on one of entries in the message list that has a downloaded RAR
segment. Then click "Combine/Decompress..." on the popup menu followed by
"Decompress RAR archive" on the secondary popup menu.
How to create RAR file sets and PAR files
News Rover is not able to produce RAR
and PAR files. To do that you need two programs: WinRAR and QuickPAR.
WinRAR is a commercial program for
decompressing and creating RAR files.
An excellent free program for using and creating PAR files is QuickPAR.
News Rover home page.
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