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- The ARJBETA Frequently Asked Questions file
-
- version 1.2, Hans Wessels & Ger Hobbelt 26-08-1995
-
- 0)
- Q: How do I contact you?
-
- A: As you all know, questions and suggestions about ARJ(beta) related
- issues is warmly welcomed at both our email addresses
- (Hans "Mr Ni!" Wessels & Ger "Insh_Allah" Hobbelt) listed at the end
- of this FAQ.
-
-
- 1)
- Q: When I am using ARJBETA, I feel like a MS DOS user, typing a lot of
- cryptic commands. Will there be an ARJ shell?
-
- A: Yes, an ARJ shell is planned. It will be programmed by Wout Klaren,
- the author of the desktop shell 'TeraDesk'. But I think it will be
- summertime before the first version is released.
- But you don't have to type at all to use ARJBETA and UNARJ; drag
- and drop is enough:
- Install ARJBETA on your (Teradesk) desktop with the following command
- line:
-
- c:\packed.arj %f
-
- Select the files, folders or drives you want to pack and drop them
- on the ARJBETA icon. They will be packed in the file
- c:\packed.arj
- or use this command line:
-
- %f %f
-
- Drop a folder <foldername> on the ARJBETA icon and the folder will
- be packed in the file <foldername>.arj
- Install UNARJ with the file type
- *.arj
- Double click on a .arj file or drop it on the UNARJ icon and the
- file will be depacked.
- Install UNARJ with the file type
- *.arj
- and use the following commandline
-
- -~g %f
-
- Double click on a .arj file or drop it on the UNARJ icon and the
- file will be depacked in a folder with de name of the file.
- As you can see: when properly installed there is no commandline
- typing at all. It's just a matter of clicking, dragging and dropping,
- something not regularly available on a MSDOS computer, even not when
- using MS Windooz.
- BTW: all examples were given with the use of TeraDesk in mind, but
- I think that any other modern desktop(shell) has the same functions
- available.
-
-
- 2)
- Q: I want to depack a file without it's directory structure; this should
- be possible with the
- e
- or
- -e
- command, but the program goes on with creating directories. What am I
- doing wrong?
-
- A: You are doing nothing wrong, the depacker was wrong. Untill
- ARJ 9.94A the
- e
- and
- -e
- commands were broken. It was not possible to depack a file without
- it's directory structure. In ARJ 9.94A the bug was fixed, but the
- -~g
- switch was always switched on (incorrect behavior according to the
- documentation). You had to switch it off using
- -~g-
- This bug was fixed in ARJ 9.95.
-
-
- 3)
- Q: What packing ratio's are you expecting compared to LHArc and STZIP?
-
- A: ARJBETA is the best packer on the ST, although there exist files that
- are better compressed with LHArc or STZIP. Especially lots of small files
- frequently result in bigger ARJ archives compared to STZIP or LHArc
- archives. This is due to the larger file headers in the ARJ archive.
- The packing ratio will improve again in the future, the current packer
- has still spots where it can be improved.
-
- This table is for ARJBETA 9.95, ARJBETA 9.96 is better.
-
- ARJBETA LHArc 3.10 STZIP 2.5
-
- Case A : Text files, 1703513 bytes used in 26 files
- packed size: 297916 321154 297350
- pack time : 141s 108s 113s
- depack time: 25s 25s 43s
-
- Case B : Degas pictures, 2077961 bytes used in 77 files
- packed size: 203349 204416 211009
- pack time : 630s 205s 312s
- depack time: 76s 79s 105s
-
- Case C : C-sources, no object files, 4365303 bytes in 168 files
- packed size: 597642 626464 612246
- pack time : 385s 317s 326s
- depack time: 142s 141s 190s
-
- Case D : Binaries, 1725316 bytes used in 26 files
- packed size: 945827 963653 953573
- pack time : 345s 239s 236s
- depack time: 45s 52s 81s
-
- Case E : Latice C5.5, 4093418 bytes used in 30 folders and 331 files
- packed size: 1854686 1889860 1890378
- pack time : 949s 535s 625s
- depack time: 288s 292s 391s
-
- Case F : Noise tracker modules, 7928196 bytes used in 39 files
- packed size: 5320479 5372994 5376083
- pack time : 1869s 1085s 908s
- depack time: 166s 213s 356s
-
- Case G : Utility drive, 28904740 bytes used in 207 folders and 1426 files
- packed size:13816829 14053261 13954665
- pack time : 6455s 3509s 4652s
- depack time: 1473s 1487s 1908s
-
- MS DOS test, 159763639 bytes used in 997 files
- MSDOS ported ARJBETA ARJ 2.42(Mr. R. Jung) PK ZIP 2.04g
- (32-bit DOS4GW app) -jm switch used
- 115118708 115318469 (+199761) 115281976 (+163268)
-
- Quick look at the new compression ratios:
- ARJBETA 9.96 Text time win31 time 4unlimit.mod Drive D: time
- m0 : 1209835 51 1156337 59 325409 13 -
- m1 : 498430 177 206785 167 209287 56 13825442 5530
- m2 : 502303 189 212983 145 210122 55 13951770 4905
- m3 : 508792 159 215649 139 211080 48 14060852 4554
- m4 : 575846 161 245563 128 242235 45 15048213 4343
- m5 : 499759 174 214375 139 210328 49 14029213 4537
- m6 : 493467 178 211868 145 209445 55 13918755 4954
- m7 : 488878 192 206744 169 208802 57 13788033 5548
- m1 -jm : 497824 203 206351 181 208811 77 13800680 6445
- m2 -jm : 201801 198 213523 163 209339 76 13928088 5849
- m3 -jm : 507775 171 215629 147 210752 58 14043104 4736
- m4 -jm : 572775 148 239050 143 241378 46 14899666 4736
- m5 -jm : 498791 173 214692 147 210073 58 14011747 4939
- m6 -jm : 492693 198 211971 164 209089 75 13895150 5841
- m7 -jm : 488119 209 205123 183 208100 77 13762916 6489
- lzh 3.10 : 537320 160 216341 133 211088 41 14078286 3620
- stzip 2.6 : 495231 190 213207 176 211508 31 13990756 4971
- arj 9.95 : 498484 270 208116 327 209424 76 13842068 6663
-
- Further speed and compression improvements are expected, especially
- mode 1, 7 and 8 (still under development) will improve. I expect the
- next ARJ will compete with the best compression programs like RAR
- and Ultracompress.
-
- 4)
- Q: What packing speed are you expecting?
-
- A: ARJBETA is not severely optimized for packing speed yet. Speed
- optimizations will start when I am finished improving packing
- ratio. Although it is hard to predict the speed of a future product
- I can say that my object is to be the fastest packer on the ST too!
- Just like the depacker being the fastest on the ST. But I know
- it will be very hard to match the packing speed of LHArc, especially
- with a complex packer like ARJBETA.
-
- ARJBETA 9.96 is a lot faster as 9.95, but most of the program is
- still C code and there is still no file buffering, so speed
- improvements are still to be expected.
-
-
- 5)
- Q: What is the difference between UNARJ and UNARJ_PR?
-
- A: UNARJ_PR is the ARJ depacker for PRogrammers. With the switch
- -~d<dumpfile>,<logfile>,<appendflag>,<dataformatflag>,
- <logformatflag>,<allignflag>,
- you can dump the contents of an archive into files. You can dump the
- archive in such a format it can be included directly into your C or
- assembley programs. You can depack the data in your program using
- the depack routines comming with the ARJ package. See for more info
- on this command de documentation of UNARJ_PR.
-
-
- 6)
- Q: Why are there so many commands and switches? I can't memorize them all!
-
- A: You don't have to know a single command or switch when your are using
- the ARJBETA packer or the UNARJ depacker (Please refer to FAQ Q #1 above
- for more on this subject). But if you want to depack files based on
- various selection schemes you can depack them by using the correct
- switches. Most of the switches were invented by Robert Jung, the author
- of the original ARJ packer on MSDOS machines. We implemented them to be
- fully compatible. The switches we added to the program are all starting
- with
- -~
- to avoid incompatibilities with future releases of Mr. Jungs archiver.
- (We thought it very unlikely for a switch to be prefixed
- -~
- so we chosed that one.)
-
-
- 7)
- Q: How do I create archives that fit on a HD disk (1.4MB)?
-
- A: You can use the switch
- -v<number>
- to enable packing in multiple volume archives. To create archive files
- that fit exactly on a disk you can use one of the following switches:
- -v180 volume size is 177152 bytes (single sided 40 x 9 disk)
- -v200 volume size is 197632 bytes (single sided 40 x 10 disk)
- -v205 volume size is 202752 bytes (single sided 42 x 10 disk)
- -v360 volume size is 360448 bytes (single sided 80 x 9 or
- dual sided 40 x 9 disk)
- -v400 volume size is 401408 bytes (single sided 80 x 10 or
- dual sided 40 x 10 disk)
- -v405 volume size is 406528 bytes (single sided 82 x 10 disk)
- -v410 volume size is 411648 bytes (dual sided 42 x 10 disk)
- -v720 volume size is 728064 bytes (dual sided 80 x 9 disk)
- -v800 volume size is 809984 bytes (dual sided 80 x 10 disk)
- -v820 volume size is 830464 bytes (dual sided 82 x 10 disk)
- -v1440 volume size is 1456640 bytes (dual side 80 x 18 (hd)disk)
- -v1600 volume size is 1623040 bytes (dual sided 80 x 20 (hd)disk)
- -v1620 volume size is 1664000 bytes (dual sided 82 x 20 (hd)disk)
- -v2880 volume size is 2913280 bytes (dual sided 80 x 36 (ed)disk)
- -v3200 volume size is 3246080 bytes (dual sided 80 x 40 (ed)disk)
- -v3240 volume size is 3328000 bytes (dual sided 82 x 40 (ed)disk)
- You can also determine the size of an archive using the following
- switch:
- -v<number> The volume size will be <number> bytes where <number>
- has to be a value larger than 8191.
- If the number is smaller than 8192 and none of the standard disk volumes
- sizes, the default size of 1456640 bytes (the size of a HD disk) will be
- assumed.
- -v without a number will fit the volume size to fill the free disk
- space on the specified diskdrive. When de disk is full you are
- prompted to insert the next disk into the drive.
-
-
- 8)
- Q: Your packer is great stuff, but my friend working at the university
- would much like it to run on the Sun machines he's got access to: he
- likes to carry his work up and down to the Atari at home. Is this
- possible in the near future or do we seek some other solution?
-
- A: As we are currently in beta development of the archiver, we do not
- miss the point about portability towards other platforms. We are
- actively porting the archiver to MSDOS 32-bit machinery (386SX or
- better) and are also in the process of making ARJBETA running on
- Linux machines.
- From there, we will embark on the path to multiple platform supporting
- ARJ; once intended by Mr Jung long ago (looking at the depacker C
- sources distributed with various ARJ versions (ARJ 2.0, 2.30, 2.41,
- etc.))
- We expect to have the 32-bit MSDOS and Linux port available before
- summer.
- Any progress in these fields will be reported on the Internet
- newsgroups: keep a close eye at comp.compression these months ;-)
-
-
- 9)
- Q: Above are listed the compression results of ARJBETA for MSDOS. Where
- can I get a copy for testing? And why are those packing ratios
- different from Mr. R. Jungs ARJ - are they compatible?
-
- A: Your first question can be easily answered: ARJBETA for MSDOS is not
- yet released - Ger Hobbelt is busy testing it, but he hasn't yet
- given a version suitable for wide-spread release.
- Second, we can only say our ARJ implementation is archive-compatible
- with Mr R. Jungs ARJ.EXE, though we use quite different tactics
- when archiving. As Hans Wessels has put quite some effort in
- developing bit-level compatible compression methods, he has hit
- upon better ways of packing. Viewing our current progress (from quite
- worse to far better ratios within a short period of development time)
- we are absolutely convinced this thingy can be stretched even farther:
- our target is to beat all well-known Atari and MSDOS based archivers
- such as PK ZIP, LHA and Mr. R. Jungs ARJ.
- I know well this quite a challenge, but we will overcome... ;-))
-
-
- 10)
- Q: Will you make a Falcon version of ARJ that will use de DSP for packing
- and/or depacking?
-
- A: No, I don't think there will ever be a special ARJ for the Falcon using
- its DSP. Because I haven't got a Falcon (and I am not planning in buying
- one, but feel free to send one, I might reconsider this statement ;-) )
- and, as far as my knowledge goes, the DSP hasn't got the right command
- set for UNARJ; it's specialized in fixed point calculations, not the
- bit-level instructions needed for ARJ (although the hardware supported
- cyclic buffers should work nice for the sliding dictionary).
-
-
- 11)
- Q: Why are ARJBETA and UNARJ seperate programs?
-
- A: Because ARJBETA is arjBETA, it is a test tool for my ARJ pack code. To
- keep the program simple it contains only the most necessary functions
- to test the packer code. In the end we will join ARJBETA and UNARJ into
- one big program.
-
-
- 12)
- Q: Where can I get in touch with you both?
-
- A: Of course we can be reached through Internet email at the
- addresses listed below:
- Hans Wessels: MR_NI@MBH.ORG or MR_NI@MST.TN.UTWENTE.NL
- Ger Hobbelt: I_A@MBH.ORG
-
-