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Don't Use RAR

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Re: Don't Use RAR

#191

Post by mmis1000 »

jillesvangurp wrote: post #157
noAnswer wrote: post #50

RAR is a full-blown backup format* while 7zip is "just" an archive format. So comparisons are somewhat mood. But even I as a RAR fan and license holder have to agree. For the average joe, sending email attachments, zip or 7z is enough. * It can safe all three file timestamps (From nanoseconds precision (with NTFS), down to only 2 seconds precision (if you want to shave of a view bytes)), ACLs, ADS, Hard and Soft Link…

I think for the common use case of distributing giga bytes of data in a reasonably efficient way, 7zip is fine (e.g. simheaven.com uses that for huge scenery downloads). Where things get tricky is splitting the resulting archive in multiple files. This used to be common with rar and I think 7zip also supports this. That is convenient when downloading over a slow/unstable connection (or if you don't know how to resume…

No, the major problem of tar is 'it is not indexable'. In any case, browse a tar means you need to scan the whole achieve to locate all files and generate the entry list. And of course it get slower when the files are a lot or archive is big. This is a format even worse than zip.(Zip do have a central record section)

And it also suffer the same problem from zip: the charset is undefined. Because they are older then the time utf-8 being the universal standard. Which means it mess up when two systems are in different charset and software is not smart enough to guess it.

These problems are all addressed in later format(rar/7z). Newer archive format most enforcing utf-8 charset. So you won't have a problem that file name suddenly turn into garbage for no reason.

It's probably the worst format you can chose if you need to distribute a file instead using it as a pack/extract on local only format(not even browse).

Re: Don't Use RAR

#192

Post by nix23 »

ValentineC wrote: post #172
nix23 wrote: post #132

Earlier quoted context omitted.

Yes please zip there too since i don't think it would be gigabytes of text. If sending gigabytes of text please use lzip ;)

> If sending gigabytes of text please use lzip ;) I had to look up lzip.

I know it's not pretty much used...but it's a great format for "important information" as you can read here:

https://en.wikipedia.org/wiki/Lzip#Application

https://www.nongnu.org/lzip/xz_inadequate.html

https://parltrack.org/dumps

Re: Don't Use RAR

#193

Post by mmis1000 »

em500 wrote: post #86
mikl wrote: post #44

Good luck trying to send a file compressed with Zstd or Brotli to people and have them know what to do with them. I’d certainly have to google to figure out how to open one of those. And I’m an engineer and aware that those formats exist.

You won't be able to do that with RAR files either. The only archive/compression format that you can send anyone is ZIP, since both Windows and macOS can open them ootb.

Except that... non ascii character filename went wrong all the time. Because zip did not enforce a charset. A rar or 7z won't mess up your filename in any case in contrast to zip.

Re: Don't Use RAR

#194

Post by Karunamon »

rcarmo wrote: post #14

There was a time when RAR was extremely popular because it dealt very well with splitting things across multiple diskette-sized archives, and because it edged out PKZIP in compression. Regardless of its origins and... "traditional" use, these days it has zero relevance given that Windows and MacOS (as well as some Linux file managers) allow you to handle zip files without any additional software - and also because ma…

OS built-in zip handling is extremely limited. You're allowed to create archives and... that's it. You have no control over the compression level or anything else.

And frankly, 7z has terrible ergonomics. Both the UI and the CLI are uncomfortable and ugly.

Re: Don't Use RAR

#195

Post by btdmaster »

ronjouch wrote: post #153
xtracto wrote: post #146

Earlier quoted context omitted.

RAR is the only archive/compression format that can include a PAR2 like recovery record. You can even configure what % of the size to dedicate for that. That has been a great killer feature for me over the years.

Confirming this, and confirming that the recovery record (that I had set to a hefty 10%, I think, because the data was important to me) did let me recover archives that suffered physical media damage, which would have been irrecoverable had I used something else. I wish 7zip had this feature. This was one of the most satisfying progress bars: from "your data is dead" to a few minutes later "Successfully recovered ful…

Par2 is always an option, and RAR implements Reed-Solomon error correcting codes and there are many recent implementations of those: https://github.com/klauspost/reedsolomon.

Re: Don't Use RAR

#196

Post by phantop »

I typically don't make use of standard archive formats these days for my own file storage. If I want just pure maximum compression, I'll often use a long-range matcher like FreeArc's srep [1] or lrzip [2] combined with either fast-lzma2 [3] using a p7zip fork [4] for multithreading and fast compression or use mcm [5] or zpaq for max ratio with longer compression time.

However, my truly preferred way is using dwarfs [6], which features some really good deduplication and (by default) zstd compression while being mountable. Most of my files are highly compressed and easily accessible without needing to full decompress them. I even made a small script to convert and create AppImages that instead use this [7]. Admittedly, I don't make use of PAR2 or anything of the sort, but I could just do that the traditional way if I so wished.

[1]: https://github.com/Phantop/srep

[2]: https://github.com/ckolivas/lrzip

[3]: https://github.com/conor42/fast-lzma2

[4]: https://github.com/jinfeihan57/p7zip

[5]: https://github.com/mathieuchartier/mcm

[6]: https://github.com/mhx/dwarfs/

[7]: https://github.com/Phantop/appdwarf/

Re: Don't Use RAR

#197

Post by ClumsyPilot »

vetinari wrote: post #64
ClumsyPilot wrote: post #42

Earlier quoted context omitted.

Its okay to have some business spesific software be closed source, say Excell. But an archive is needed every time you download a collection of files from a government website, or make GDPR request for your data to google. So by choosing RAR you would be forcing millions of people, maybe entire country to use that company's product and giving them power. Is there any good reason for that?

And what's the difference compared to forcing docx/xlsx or psd? The network effects affect every exchange, not just archives.

If a government forces it's people to use particular software, it has a duty to provide that software to the entire population. If a parliament decides to pay $X billion to Microsoft, for a lisence for all of UK, well, that sucks, but they can fight over it like they do with all other random spending they do.

If it's not willing to pay the cost, it is basically creating a monopoly for that firm, and I have to pay for it. The potential for lobbying and corruption is off the scale here.

Re: Don't Use RAR

#198

Post by ronjouch »

btdmaster wrote: post #195
ronjouch wrote: post #153

Earlier quoted context omitted.

Confirming this, and confirming that the recovery record (that I had set to a hefty 10%, I think, because the data was important to me) did let me recover archives that suffered physical media damage, which would have been irrecoverable had I used something else. I wish 7zip had this feature. This was one of the most satisfying progress bars: from "your data is dead" to a few minutes later "Successfully recovered ful…

Par2 is always an option, and RAR implements Reed-Solomon error correcting codes and there are many recent implementations of those: https://github.com/klauspost/reedsolomon .

I'm sure there is a public algorithm / implementation. My question here is: is there an existing archive format (like .7z) that integrates it to the archive format and knows to update the error-correction data on archive update? Maybe not in a way that is as user-friendly as RAR, but "halfway there".

Or are you suggesting all my .7z files should come with a sibling .par2, that I must remember to regenerate after every change of the .7z ? I know I was asking here about "Usability-aside alternatives", but that alternative seems quite inconvenient and below the bar I was ready to accept when asking for less-user-friendly stuff.

Re: Don't Use RAR

#199

Post by ryandrake »

dole wrote: post #178
kosasbest wrote: post #165

Interesting that the warez scene adopted RAR as the standard for packaging up pirated works. The alternatives like 7z save more bytes, yet RAR somehow became the winner. Anyone know why?

RAR's initial release was 1993, 7z's 1999. IIRC, I remembered seeing RAR's in the scene around 1995, 1996 or so. My take: RAR handled splitting to multiple arbitrary-sized volumes more gracefully than ARJ/ARC which were CLI first and never had a Windows GUI that was as nicely polished as WinRAR was. SFVs made error checking and redownloading corrupted volumes easy without relying on the compression format to handle i…

> I remembered seeing RAR's in the scene around 1995, 1996 or so. My take: RAR handled splitting to multiple arbitrary-sized volumes more gracefully than ARJ/ARC which were CLI first and never had a Windows GUI that was as nicely polished as WinRAR was.

Of course there were still people who screwed that up. I remember downloading some software once that came in the form of a multi-volume RAR, maybe 20 floppy disk-sized RARs. Download all 20 of them, get them in the same directory, then un-rar them, and lo and behold out the other end comes a single .RAR file that was inside! So I un-rar that single RAR, and out the other end comes 20 separate floppy disk images. Obviously the "scene" distributors weren't always the computing world's best and brightest...

Re: Don't Use RAR

#200

Post by duskwuff »

mmis1000 wrote: post #191
jillesvangurp wrote: post #157

Earlier quoted context omitted.

I think for the common use case of distributing giga bytes of data in a reasonably efficient way, 7zip is fine (e.g. simheaven.com uses that for huge scenery downloads). Where things get tricky is splitting the resulting archive in multiple files. This used to be common with rar and I think 7zip also supports this. That is convenient when downloading over a slow/unstable connection (or if you don't know how to resume…

No, the major problem of tar is 'it is not indexable'. In any case, browse a tar means you need to scan the whole achieve to locate all files and generate the entry list. And of course it get slower when the files are a lot or archive is big. This is a format even worse than zip.(Zip do have a central record section) And it also suffer the same problem from zip: the charset is undefined. Because they are older then t…

Technically speaking, TAR is indexable -- the index is distributed through the archive, at the head of each file. So long as the TAR is uncompressed, you can skip from one header to the next by reading the size of each file. It ends up looking like a bunch of random I/O, but it's manageable. (The headers are even sector-aligned!)

The problem arises when the TAR is compressed with a stream compressor (as most are). Since stream compression formats generally aren't seekable, there's no way to read each header without uncompressing the rest of the file in the process.

> And it also suffer the same problem from zip: the charset is undefined. Newer archive format most enforcing utf-8 charset.

On the flip side, this means that those archive formats can't archive the contents of a filesystem which contains inconsistently encoded (or flat-out nonsense) filenames.

So long as filesystems haven't "solved" the encoding problem, I wouldn't fault an archive format for behaving similarly.

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