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---------------------------------- unPACKIT: for the IBM PC ---------------------------------- PACKIT file unpacker ---------------------------------- unPACKIT is distributed freely and may be copied by anyone for any number of machines. The author considers unPACKIT to be "shareware" or "freeware". unPACKIT is a part of the shareware package PC-VCO. If you have subscribed to PC-VCO, unPACKIT is released for your use. If you wish to use unPACKIT 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: R. (Scott) McGinnis P.O. Box 3607 Mdse Mart Chicago, IL 60654-0607 PLINK id: TARTAN Version 1.0: 861021 R.McGinnis; Chicago unPACKIT: PACKIT file extractor Version 1.0: 861021 Table of Contents ----------------- I. Introduction ................................................. page 1 II. Running the program .......................................... page 3 III. unPACKIT Command Summary ...................................... page 4 IV. unPACKIT 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. PACKIT File structure ......................................... page 10 C. PACKIT Subfile structure ...................................... page 11 D. unPACKIT Error messages ....................................... page 12 unPACKIT: PACKIT file extractor Page 1 Version 1.0: 861021 I. Introduction unPACKIT for the IBM PC is a utility that extracts files packed together on a MacIntosh computer with the PACKIT utility. PACKIT on the Mac- Intosh will pack multiple files together (optionally compressing and encoding them) into one file. unPACKIT on the IBM PC allows the extraction of individual files from the PACKIT envelope. Many files maintained as '.PIT' (the usual PACKIT extension) on Mac BBS's, Clubs, and SIG's are now accessible to users of the IBM PC. PACKIT was developed and has been extended by Harry Chesley. PACKIT I (the original version) simply stored files together, with error checks designed into the construction. PACKIT II added compression to the PIT file. PACKIT III added data encryption - simple encryption and DES encryption - as options. PACKIT versions I/II/III is available as shareware from Harry Chesley. unPACKIT is compatible with PACKIT I and II. Data encryption is not supported. unPACKIT 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 unPACKIT used to extract individual face files. unPACKIT may be copied freely and distributed to anyone for any number of machines. The author considers this to be "shareware" or "freeware" unPACKIT is a part of the shareware package PC-VCO. If you have sub- scribed to PC-VCO, unPACKIT is released for your use. If you wish to use unPACKIT without subscription to PC-VCO, a contribution is asked. unPACKIT (and PC-VCO/unPACKIT) will be extended and enhanced if response warrants. unPACKIT: PACKIT file extractor Page 2 Version 1.0: 861021 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 PACKIT. The files will be found in the library areas with the extension of '.PIT'. And thus unPACKIT for the IBM PC ! unPACKIT: PACKIT file extractor Page 3 Version 1.0: 861021 II. Running the program unPACKIT is invoked at the DOS prompt with the command: ------------------------------------------------------ "d>" unPACKIT <option> Where "d>" is the DOS prompt, and <option> is: (<switch> or <cmd> <PIT-File> (<parm> (,<parm> ...))) where <switch> is one of the following: /+, /-, /B, /D, /R <parm> is a subfile name, <PIT-file> is the PACKIT 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. ------------------------------------------------------ unPACKIT commands and switches are summarized on the next pages. unPACKIT: PACKIT file extractor Page 4 Version 1.0: 861021 III. unPACKIT 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 PIT 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: PMag - simple compression (PACKIT I) PMa4 - huffman compressed (PACKIT II) PMa5 - compressed and encrypted (PACKIT III) PMa6 - compressed and DES encrypted (PACKIT III) Note: unPACKIT can only deal usefully with compression types "PMag" and "PMa4". (V)erbose List the subfiles of the specified PIT file. If a parameter is given it will be ignored. The verbose list give 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. unPACKIT: PACKIT file extractor Page 5 Version 1.0: 861021 IV. unPACKIT Switches. unPACKIT uses switches to control its output format. In order to explain these switches, some preliminary explanation is required. Bear with me 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 PIT file used by unPACKIT must have a MacBinary header, with a type of "PIT " and a creator of "PIT ". 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, unPACKIT 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. unPACKIT: PACKIT file extractor Page 6 Version 1.0: 861021 V. VCOLIB usage. Face files packed together into one PIT 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 can easily find the file FACES1.PIT in the CIS MacIntosh Users Group (MAUG) library (DL). Download 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>" unPACKIT L FACES1.PIT (assuming that is the name you gave it) Extract an individual face with the command: "d>" unPACKIT X FACES1.PIT <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> unPACKIT: PACKIT file extractor Page 7 Version 1.0: 861021 VI. Program Requirements Version 1.0 of unPACKIT 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 PIT file with the command: d> unPACKIT >TEMP.TXT L JAPANART.PIT ; 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> unPACKIT <TEMP.TXT X JAPANART.PIT ; It doesn't work! the program terminates abnormally. If this program is extended, this feature will be one of the first addressed. unPACKIT will accept the 'X' command with no operand and unpack the entire contents of the PIT file. The command above (without the redirection of input, of course) is an example. Simply enter: d> unPACKIT X <PIT file name> and every file within the PIT 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. unPACKIT will run in 64K. unPACKIT: PACKIT file extractor Page 8 Version 1.0: 861021 VIII. Program and Author Information This program was written using Microsoft Macro-Assembler. The author likes assembler. Assembly language is an entirely appropriate vehicle for the program. unPACKIT, VCOLIB and PC-VCO were written by R. Scott McGinnis of Chicago Illinois. [PLINK ID is TARTAN]. Comment and suggestions are welcomed. 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 and Mike Cohen. Both Kelly and Mike helped me make unPACKIT and PC-VCO possible. I must also thank my wife, Elizabeth, who has helped me at every step, and smiled upon my vagaries. unPACKIT (Version 1.1) 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". unPACKIT is a part of the shareware package PC-VCO. If you have subscribed to PC-VCO, unPACKIT is released for your use. If you wish to use unPACKIT without subscription to PC-VCO, a contribution of $10.00 is requested. unPACKIT (and PC-VCO/unPACKIT) 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. unPACKIT: PACKIT file extractor Page 9 Version 1.0: 861021 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 "PIT ". Creator ---> Creator of file field. We expect "PIT ". unPACKIT: PACKIT file extractor Page 10 Version 1.0: 861021 Appendices B. PACKIT file structure. The PACKIT file is a concatenated series of subfiles, with a MacBinary Header. After the MacBinary header, a PACKIT file looks like: +------+------+------+------+--// ! Type (4 bytes) ! Subfile 1 +------+------+------+------+--// +------+------+------+------+------+------+--// ! 1st subfile contents (variable length) ! +------+------+------+------+------+------+--// +------+------+------+------+--// ! Type (4 bytes) ! Subfile 2 +------+------+------+------+--// +------+------+------+------+------+------+--// ! 2nd subfile contents (variable length) ! +------+------+------+------+------+------+--// ... And so on. Lastly, there is: +------+------+------+------+--// ! EOF Type (4 bytes) ! +------+------+------+------+--// Type Contents ---- --------------------------------------------------- "PMag" Simple packed file "PMa4" Compressed subfile (huffman encoded) "PMa5" Compressed subfile (huffman) and simple encryption "PMa5" Compressed subfile (huffman) and DES encrypted "PEnd" EOF indicator unPACKIT: PACKIT file extractor Page 11 Version 1.0: 861021 Appendices C. PACKIT Subfile structure. Each subfile is structured: +------+------+------+------+ ! Header ! +------+------+------+------+ ! ! / / Data fork / / ! ! +------+------+------+------+ ! ! / / Resource fork / / ! ! +------+------+------+------+ ! Data/Resource CRC ! +------+------+------+------+ ------------------------------------------------------------ The header has the following structure: Field Length Contents ------- ------- -------------------------------------------- NameLen 1 Length of NAME field in bytes (1-63) Name 63 Name of subfile Type 4 File type (as type above in MacBinary header) Creator 4 File creator (as creator above) Flags 1 Finder flags 1 one byte of filler to preserve word alignment Locked 2 File locked if non-zero DSize 4 32 bit count of bytes in data fork RSize 4 32 bit count of bytes in resource fork CrDate 4 file creation date ! Count in seconds since ModDate 4 file last modified ! Jan 1, 1904 CRC 2 CRC for above header ------------------------------------------------------------ Note: If the subfile type indicates compression, the header as described above is compressed along with the data and the resource forks. The DSize and RSize fields refer to the un- compressed file size... therefore the entire subfile must be uncompressed in order to get to the next subfile! ------------------------------------------------------------ unPACKIT: PACKIT file extractor Page 12 Version 1.0: 861021 Appendices D. unPACKIT Error messages. ------------------------------------------------------------ ... Parameter error The command line, as entered after the invocation of unPACKIT could not be interpreted. Re-type the command line. ------------------------------------------------------------ ... File name syntax error unPACKIT 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. unPACKIT could not interpret the expected name. ------------------------------------------------------------ ... File is not PACKIT format The file specified is not identified as a PACKIT file in its MacBinary header (the first 128 bytes). Type must be "PIT " and creator "PIT ". ------------------------------------------------------------ Short read reading subfile header The PACKIT file has been truncated - only part of its contents are available for extraction. ------------------------------------------------------------ Warning: Subfile header CRC does not match computed CRC. The PACKIT 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 PACKIT file has been corrupted, or a PACKIT IV has been released. ------------------------------------------------------------ Position past EOF requested. The PACKIT 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 (again) may have a bug. ------------------------------------------------------------ Warning: Subfile contentual CRC does not match computed CRC. The PACKIT 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.