Thread: [See Bugtracker] Extract when unselected
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Old 11.03.2010, 06:12
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drbits drbits is offline
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I am sorry Gweilo, I do not mean to be condescending.

The three times the disk space you think you need rule of thumb is not as important as it used to be, but it is always a good guideline.

JD will eventually check disk space before performing most tasks. It just has not gotten there yet. I think that will come after some of the major internal changes.

I have not seen any other archive types than Zip in which a segmented archive looks so much like a split file.

@ Jiaz,
I like the idea of a blacklist better than a whitelist.

The number of extensions in use is at least in the tens of thousands. A large percentage of them grow big enough to split (over 1.44 MB, but realistically 15,000,000 bytes). Fortunately, the traditional Unix and MacOS used tar and sit, which are not multivolume. The OSX and Linux installers use many different extensions, some of them are zip or 7z volumes and some are splits. Even Jar files come both ways (but are more likely splits, unless it is part of a scene release). Because of tar, the Unix/Linux users got used to splits. Windows users are not used to splits.

The way to distinguish a split Zip from a multivolume Zip is to look at the first two bytes of each file. If they are all PK it is a multivolume. Since you cannot tell a Zip file from its extension, you always have to check this. I believe the same applies to RAR and 7z (different signatures). With early zip files, you could merge volumes and unzip. More modern versions do not always merge into a usable file (an index is allowed only at the end of a volume and they have started distributing the index in some cases).

Whatever you use has to check again after extraction/Merging. Scene releases of music or a small group of files are normally 15,000,000 bytes. These are usually rar (a few use zip). If the data is large enough the scene uses 50,000,000 bytes (15 files per full CD). Many RS or HF files are rar containers (no compression), containing a scene release. The RS and scene sizes do not divide evenly.

Sorry I got carried away.
drbits

Last edited by drbits; 11.03.2010 at 06:17.
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