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---------------------------------- unStufit: for the IBM PC ---------------------------------- STUFFIT file unpacker ---------------------------------- unStufit is distributed freely and may be copied by anyone for any number of machines. The author considers unStufit to be "shareware" or "freeware". unStufit is a part of the shareware package PC-VCO. If you have subscribed to PC-VCO, unStufit is released for your use. If you wish to use unStufit without subscription to PC-VCO, please support its development and main- tenance with a subscription of 10.00 dollars. The author may be reached at: CABER Software R. (Scott) McGinnis P.O. Box 3607 Mdse Mart Chicago, IL 60654-0607 PLINK id: TARTAN Version 1.0: 880211 R.McGinnis; Chicago unStufit: STUFFIT file extractor Version 1.0: 880211 Table of Contents ----------------- I. Introduction ................................................. page 1 II. Running the program .......................................... page 3 III. unStufit Command Summary ...................................... page 4 IV. unStufit Switches ............................................. page 5 V. VCOLIB usage .................................................. page 6 VI. Batch extraction .............................................. page 7 VII. Program Requirements .......................................... page 7 VIII. Program and Author Information ............................... page 8 Appendices ---------- A. MacBinary Header .............................................. page 9 B. STUFFIT File structure ........................................ page 10 C. STUFFIT Archive Header ........................................ page 11 D. STUFFIT Subfile Header ........................................ page 12 E. unStufit Error messages ....................................... page 13 unStufit: STUFFIT file extractor Page 1 Version 1.0: 880211 I. Introduction unStufit for the IBM PC is a utility that extracts files packed together on a MacIntosh computer with the STUFFIT utility. STUFFIT on the MacIntosh will pack multiple files together (optionally compressing and encoding them) into one file. unStufit on the IBM PC allows the extraction of individual files from the STUFFIT envelope. Many files maintained as '.SIT' (the usual STUFFIT extension) on Mac BBS's, Clubs, and SIG's are now accessible to users of the IBM PC. STUFFIT was developed and has been extended by Raymond Lau. STUFFIT (through version 1.20) stored files together, with non-compression and 3 optional types of data compression. STUFFIT is available as shareware. unStufit is compatible with STUFFIT. unStufit was developed to support the shareware package PC-VCO for the IBM PC. Face files created on MacIntosh computers are frequently packed together on the various boards: PLINK, CIS, Delphi, and GEnie. Now packed face files are available to PC-VCO users. A packed file may be downloaded to an IBM PC and unStufit used to extract individual face files. unStufit may be copied freely and distributed to anyone for any number of machines. The author considers this to be "shareware" or "freeware" unStufit is a part of the shareware package PC-VCO. If you have sub- scribed to PC-VCO, unStufit is released for your use. If you wish to use unStufit without subscription to PC-VCO, a contribution is asked. unStufit (and PC-VCO/unStufit) will be extended and enhanced if response warrants. unStufit: STUFFIT file extractor Page 2 Version 1.0: 880211 I. Introduction (continued) What is PC-VCO, by-the-way? PC-VCO is a communications program for the IBM PC with two sides. On the one hand, it provides standard comm program functions: a dialing directory, macros, disc logging, XMODEM and ASCII file transfer, and so on. However, used with network conferencing services such as People/Link's PARTY, CompuServe's CB and Delphi's conference area, PC-VCO provides a way to 'see' and 'hear' people talking. The idea for PC-VCO was derived from the VCO system, and its predecessor VMCO, developed for the MacIntosh computer. The VCO programs (PC and MacIntosh) allow you to see the people you communicate with on-line, using the graphic capabilities of the personal computer and to hear conversation with speech synthesis. VCO was originally developed by Harry Chesley. It was followed by VMCO (which is CIS specific), written by Bob Perez independant to the development of VCO. The current (MacIntosh) version of VCO is almost an exact duplicate of Harry Chesley's original - the original source code was converted by Mike Cohen and made to accept multiple service formats. [Note: Mike Cohen's VCO uses VMCO formated files. Harry Chesley's VCO files differ. VCOLIB can accomodate either. PC-VCO in VCO mode can talk to either, according to your choice.] The MacIntosh VCO allows the user to see the people talking on-line through graphic Icons. The Icons are provided to the VCO program as 'Resource files' and are built using a 'Resource Editor'. Each VCO user must have a resource file for every potential other speaker. Charlie Brown and Snoopy Icons are used if no 'Faces' are available. A range of expressions, from 'normal' to bored to surprised make VCO conferences lively. Each participant controls the expression displayed to all other participants. On most large systems, the face files for 20 or more people have been packed (and compressed) together with the shareware product STUFFIT. The files will be found in the library areas with the extension of '.SIT'. And thus unStufit for the IBM PC ! unStufit: STUFFIT file extractor Page 3 Version 1.0: 880211 II. Running the program unStufit is invoked at the DOS prompt with the command: ------------------------------------------------------ "d>" unStufit <option> Where "d>" is the DOS prompt, and <option> is: (<switch> or <cmd> <SIT-File> (<parm> (,<parm> ...))) where <switch> is one of the following: /+, /-, /B, /D, /R <parm> is a subfile name, <SIT-file> is the STUFFIT file name to be used, and <cmd> is one of the following: E,X,L,V Note: Specifying no commands at all will provide an abbreviated HELP display summarizing available commands. ------------------------------------------------------ unStufit commands and switches are summarized on the next pages. unStufit: STUFFIT file extractor Page 4 Version 1.0: 880211 III. unStufit Command Summary. Command Parameter Description --------- --------- -------------------------------------------------- (E)xtract subfile Extract the specified subfile. Subfile names are name listed with the 'L' or 'V' commands. Subfile names are up to 63 bytes in length, and may not contain a comma or a semi-colon. Case is not significant. (X)tract subfile Extract the specified subfile. This is simply a name synonym for the 'E' command discussed above for those of us who spell phonetically. (L)ist List the subfiles of the specified SIT file. If a parameter is given it will be ignored. The list command gives the following information: Subfile name (1-63 characters in length) File Type (4 characters) File creator (4 characters) Compression. Compression types are: 0 - non-compression 1 - repeat character compression (RLE) 2 - dynamic Lempel-Ziv,Weiss compression 3 - Huffman compression (V)erbose List the subfiles of the specified SIT file. If a parameter is given it will be ignored. The verbose list gives the information above and the following: Data Fork size: Byte count in the subfile's Data fork. Resource Fork size: Byte count in the subfile's Resource fork. Creation date: Date the file was created. Modification date: Date the file was last modified. unStufit: STUFFIT file extractor Page 5 Version 1.0: 880211 IV. unStufit Switches. unStufit uses switches to control its output format. In order to explain these switches, some preliminaries are required. Bear with me, please, if you already understand the following points: . Files uploaded by a MacIntosh and downloaded by an IBM PC will have a header called 'MacBinary'. The MacBinary header gives specifics about the file's name, type/creator, etc. The SIT file used by unStufit must have a MacBinary header, with a type of "SIT!" and a creator of "SIT!". VCOLIB (the face file librarian for PC-VCO) expects face files offered it for ingestion to have a MacBinary header. . MacIntosh files are implemented as 'forks'... each file has a 'Data' and a 'Resource' fork. The Data fork is what we who use IBM PC's understand to be a file - it is object code, data, a data base, what-have-you. The Resource fork contains O/S information such as the ICON to be displayed to represent the file. Again using VCOLIB as an example: VCOLIB uses only the resource fork of a face file. And I don't know why the whole construction isn't referred to as a fork, and the elements 'tines'. With this understood, unStufit offers the following switches (which must be entered prior to the command(s) effected): Switch Description ------- ------------------------------------------------------------ /+ Default condition. A MacBinary header is created for each file extracted (with the appropriate name, type and creator). /- No MacBinary header will be output with extracted files. This would be appropriate if, for example, an encrypted file were being uncompressed and encryption performed separately. /B Default condition. Both the Data and Resource forks are to be extracted (if present). Each will be output as a separate file on the IBM PC (the name for each file will be queried). /D Only the Data fork is to be extracted. The Resource fork will be skipped if present. /R Only the Resource fork is to be extracted. The Data fork will be skipped if present. unStufit: STUFFIT file extractor Page 6 Version 1.0: 880211 V. VCOLIB usage. Face files packed together into one SIT file will have certain characteristics. First of all, the Data fork for each subfile will be empty (size is 0 bytes). Only the Resource fork is used. VCOLIB will only accept resource files with one of the following type/creator values: Type Creator Usage ---- ------- -------------------------------------------- FACE VCO! File created for use with Mike Cohen's VCO (this version is mostly used on PLINK) FACE VMCO File created for use with Bob Perez's VMCO (this version is mostly used on CIS) HRC1 HRC1 File created for use with Harry Chesley's VCO (this version is mostly used on GEnie and Delphi) For example: you might find a face-file Stuffit archive in the CIS MacIntosh Users Group (MAUG) library (DL) named FACES1.SIT. Down- load the file using an error free binary protocol. It will be seen to conform to the above description (0 size data forks, and type/creator of "FACEVMCO". List the file's contents with the command: "d>" unStufit L FACES1.SIT (assuming that is the name you gave it) Extract an individual face with the command: "d>" unStufit X FACES1.SIT <somebody's name from the listing> You will be queried for the file name for the extracted subfile. Choose any name (the face file itself contains the original name, so the name you use for the file is relatively unimportant) that does not conflict with a file already on your diskette/subdirectory. Add the extracted file to PC-VCO's face library with the command: "d>" VCOLIB A <your library file> <the extracted file's name> Normally, the library file would be PC-VCO.FLB. You may view the entry with the command: "d>" VCOLIB V <your library file> <the name as it was originally> unStufit: STUFFIT file extractor Page 7 Version 1.0: 880211 VI. Batch Extraction Version 1.0 of unStufit allows redirection of the output (e.g. of the 'L' command to the printer. However, redirection of input is not supported. Although it may appear obvious to build a contents list of a SIT file with the command: d> unStufit >TEMP.TXT L JAPANART.SIT ; This works just nicely and then edit the result - providing blank (empty) lines for files to be skipped - it won't work. When the edited file is presented to be processed, e.g. with the command: d> unStufit <TEMP.TXT X JAPANART.SIT ; It doesn't work! the program terminates abnormally. If this program is extended, this feature will be one of the first addressed. unStufit will accept the 'X' command with no operand and unpack the entire contents of the SIT file. The command above (without the redirection of input, of course) is an example. Simply enter: d> unStufit X <SIT file name> and every file within the SIT file will be unpacked. You can skip a subfile with a null entry - a carriage return) at the file name prompt. And its faster than a selective extraction. Another matter to be addressed if response warrants. VII. Program Requirements This program can only function on an IBM PC or DOS compatible machine. It uses 'Handle' oriented I/O routines added with DOS 2.0. Therefore DOS 2.0 is also a requirement. The current version's memory requirements are modest. unStufit requires 96K - you'll need at least 128K. unStufit: STUFFIT file extractor Page 8 Version 1.0: 880211 VIII. Program and Author Information This program was written using Microsoft Macro-Assembler, version 5.0. The author likes assembler. Assembly language is an entirely appropriate vehicle for the program. unStufit, VCOLIB and PC-VCO were written by R. Scott McGinnis of Chicago Illinois. [GEnie and PLINK IDs: TARTAN]. Comment and suggestions are welcomed. You may also write: CABER Software R. (Scott) McGinnis P.O. Box 3607 Mdse Mart Chicago, IL 60654-0607 Credit for information on the MacIntosh must be given to Kelly Major. Experience with PACKIT files contributed directly to this code, as did the public domain source for ARC. I also thank Elizabeth, for putting up with the repeated jaw-breaker: "Lempel-Ziv this and Lempel- Ziv that...". unStufit (Version 1.0) may be distributed freely, with the caveat that the Author information displayed at program termination is not removed. The author considers this to be "shareware" or "freeware". unStufit is a part of the shareware package PC-VCO. If you have subscribed to PC-VCO, unStufit is released for your use. If you wish to use unStufit without subscription to PC-VCO, a contribution of $10.00 is requested. unStufit (and PC-VCO/unStufit) will be extended and enhanced if response (measured by contribution) warrants. Most of the hardware names and software names (and products not hardware or software) mentioned in this document are trademarks or trade names of specific manufacturers. unStufit: STUFFIT file extractor Page 9 Version 1.0: 880211 Appendices A. MacBinary header. The MacBinary header is 128 bytes in length, and structured: 0 1 2 3 4 5 6 7 65 +------+------+------+------+------+------+------+-----/ /-----+-> ! Ver ! FLN ! File Name ... ! +------+------+------+------+------+------+------+-----/ /-----+-> 65 66 67 68 69 70 71 72 73 >--+------+------+------+------+------+------+------+------+-> ! Type ! Creator ! >--+------+------+------+------+------+------+------+------+-> 73 74 ... 126 127 >--+------+-----/ /-----+------+ ! Unused by us ! >--+------+-----/ /-----+------+ Where: Ver -------> MacBinary Version Number FLN -------> Len of following File name (value 0-63) File Name -> File Name; Used here as Creator ID. Type ------> Type of file field. We expect "SIT!". Creator ---> Creator of file field. We expect "SIT!". unStufit: STUFFIT file extractor Page 10 Version 1.0: 880211 Appendices B. STUFFIT file structure. The stuffit file is a concatenated series of subfiles, with a MacBinary Header. After the MacBinary header, a stuffit file looks like: sitArchiveHdr file1Hdr (uncompressed) file1RsrcFork (possibly compressed) file1DataFork (possibly compressed) file2Hdr ... file2RsrcFork ... file2DataFork ... . . . fileNHdr fileNRsrcFork fileNDataFork unStufit: STUFFIT file extractor Page 11 Version 1.0: 880211 Appendices C. STUFFIT Archive Header OSType signature; /* = 'SIT!' -- for verification */ unsigned int numFiles; /* number of files in archive */ unsigned long arcLength; /* length of entire archive incl. hdr. -- for verification */ OSType signature2; /* = 'rLau' -- for verification */ unsigned char version; /* version number */ char reserved[7]; ----------------------------------------------------------- The header has the following structure: Field Length Contents ------- ------- -------------------------------------------- Sig1 4 Type field for verification (SIT!) NumF 2 COunt of files in archive Len 4 Archive length (in bytes) Sig2 4 Type field for verification (rlau) Version 1 Version number Fill 7 reserved for future unStufit: STUFFIT file extractor Page 12 Version 1.0: 880211 Appendices D. Stuffit Subfile Header unsigned char compRMethod; /* rsrc fork compression method */ unsigned char compDMethod; /* data fork compression method */ unsigned char fName[64]; /* a STR63 */ OSType fType; /* file type */ OSType fCreator; /* erI */ int FndrFlags; /* copy of Finder flags. unsigned long creationDate; unsigned long modDate; /* !restoredPcompat w/backup prgms */ unsigned long rsrcLength; /* decompressed lengths */ unsigned long dataLength; unsigned long compRLength; /* compressed lengths */ unsigned long compDLength; int rsrcCRC; /* crc of rsrc fork */ int dataCRC; /* crc of data fork */ char reserved[6]; int hdrCRC; /* crc of file header */ ------------------------------------------------------------ The header has the following structure: Field Length Contents ------- ------- -------------------------------------------- RMethod 1 Resource fork compression method DMethod 1 Data fork compression method NameLen 1 Length of NAME field in bytes (1-63) Name 63 Name of subfile Type 4 File type (as above) Creator 4 File creator (as creator above) Flags 1 Finder flags 1 one byte of filler to preserve word alignment CrDate 4 file creation date ! Count in seconds since ModDate 4 file last modified ! Jan 1, 1904 RSize 4 32 bit count of bytes in resource fork DSize 4 32 bit count of bytes in data fork CDSize 4 32 bit count of compressed bytes in data fork RSize 4 32 bit count of compressed bytes in resource fork Fill 6 reserved for future CRC 2 CRC for above header ------------------------------------------------------------ Note: the CRC's used in Stuffit are computed as ARC computes CRC's - not CCITT CRC-16 at all!. ------------------------------------------------------------ unStufit: STUFFIT file extractor Page 13 Version 1.0: 880211 Appendices E. unStufit Error messages. ------------------------------------------------------------ ... Parameter error The command line, as entered after the invocation of unStufit could not be interpreted. Re-type the command line. ------------------------------------------------------------ ... File name syntax error unStufit follows the SEA/ARC convention of placing the file name of the file to be manipulated after the first command and before the parameters of that first command. unStufit could not interpret the expected name. ------------------------------------------------------------ ... File is not STUFFIT format The file specified is not identified as a STUFFIT file in its MacBinary header (the first 128 bytes). Type must be "SIT!" and creator "SIT!". ------------------------------------------------------------ Short read reading subfile header The STUFFIT file has been truncated - only part of its contents are available for extraction. ------------------------------------------------------------ Warning: Subfile header CRC does not match computed CRC. The STUFFIT file has been corrupted. Or the author has a bug. If the file is downloaded a second time, and the error persists, its probably a bug. Please contact the author. ------------------------------------------------------------ Subfile type unrecognized. The STUFFIT file uses a compression method other than those above. ------------------------------------------------------------ Position past EOF requested. The STUFFIT file has been truncated - only part of its contents are available for extraction. ------------------------------------------------------------ Huffman tree is corrupt. I can not use it. Decoding information could not be loaded from a compressed file. The file could be corrupt, or the author (me, again) may have a bug. ------------------------------------------------------------ Warning: Subfile contentual CRC does not match computed CRC. The STUFFIT file has been corrupted. Or the author has a bug. If the file is downloaded a second time, and the error persists, its probably a bug. Please contact the author.