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Zoo A Fast File Archiver Version 1.10 - 24 August 1986 by Rahul Dhesi INTRODUCTION Zoo is a utility for creating and maintaining libraries or archives of files in compressed form. It requires a computer system with MS-DOS version 2.00 or greater. IBM compatibility is not a requirement. Zoo is a 29 kilobyte executable file. It can extract archived files in about 80 kilobytes of available memory, and can function fully in about 110 kilobytes of available memory. A companion program, Ooz, is also provided. All that Ooz can do is extract files from Zoo archives, but it occupies less disk space (about 11 kilo- bytes) and needs less available memory (about 60 kilobytes). Also provided is AtoZ, a batch program that will convert a subdirectory full of files in other formats (especially *.LBR or *.ARC) to Zoo archives. Versions 1.x of Zoo, Ooz and AtoZ are in the public domain. This means that you can freely use them, make copies, give them away, and even sell them. The source code is not being distributed, but version 2.00 of Zoo, when it appears, will be accompanied by generic source code in C. DISCLAIMER Zoo, Ooz, and Atoz are provided to you on an "as is", "you owe me nothing, I owe you nothing" basis. If this warranty gives you any specific legal rights, I would like to know what they are, especially if they vary from state to state. COMMAND SUMMARY Zoo has two types of commands: Expert commands, which consist of one com- mand letter followed by zero or more modifier characters, and Novice com- mands, which consist of a hyphen ("-") followed by a command word that may be abbreviated. Novice commands let you begin using Zoo quickly. Unlike Expert commands, which are case-sensitive, Novice commands can be given in any combination of upper- and lowercase characters. Expert commands are cryptic but offer you many more flexible options. Start with the Novice commands and switch to using the Expert commands as soon as you can. 1. Zoo Novice Command Format: ZOO cmd archive[.ZOO] [file] ... The "archive" is the filename of the archive you want to use, and the program will assume an extension of ".ZOO" if you do not supply one. The "file" is any filespec. Both the "archive" and the "file" names may be pathnames. Pathnames may contain both "/" and "\" characters. The "file" name (but not the "archive" name) may also contain the standard DOS-style wildcard characters "*" and "?". The "..." means that several filespecs may be given, separated by spaces. A filespec ending with "/" or "\" is assumed to refer to all files in that directory. Each Novice command works in two stages. First, the command does its inten- ded work. Then, if the result was that one or more files were deleted in the specified archive, the archive is packed to recover space. If packing occurs, an unpacked backup copy of the archive is always left behind, with an extension of ".bak". The packed archive always appears in the current directory, even if the original archive was on a different disk. This is intended to allow you to economize on disk space by simply using two disks if there is not enough space on a single disk to hold both the archive and its backup copy. Novice Equivalent Command Description Expert Command ------- ----------- -------------- -add add files to archive aP -extract extract files from archive x -move move files to archive aMP -test test archive integrity xNd -print extract files and send to standard output xp -delete delete files from archive DP -list list information about archived files l -update update archive by adding new or newer files aunP -freshen freshen archive by adding newer files auP -comment allows user to attach comments to files c Novice commands may be abbreviated as much as you wish, up to a minimum of a hyphen ("-") followed by at least one command character. For example, the novice command "-extract" may be abbreviated to "-ext", "-ex", or "-e". Novice commands are described in more detail later. 2. Zoo Expert Command Format: ZOO {acDehlPTuUvx}[dEfnMNoOpPquv1] archive[.ZOO] [file] ... The characters enclosed within {} are commands. Choose any one of these. The characters enclosed within [] just to the right of the {} are modifiers and zero or more of these may immediately follow the command character. All combinations of command and modifier characters may not be valid. In general, [] encloses something that may (sometimes) be omitted and {} encloses a set of items from which exactly one must be selected. The archive and file names are as described for Novice commands above. The archive and file names may be in any combination of upper- and lowercase characters, but the command and modifier characters are case-sensitive. Invoking Zoo as "zoo h" will give a help screen. Zoo Expert commands are described in detail later. 3. Ooz Command Format The Ooz command format is as follows: OOZ archive[.ZOO] [file] ... Ooz is trivial to use; just give it the name of the archive and it will extract all files from it, or specify which files you want to extract and only those will be extracted. All extracted files go into the current directory. NOVICE COMMANDS 1. Adding Files to an Archive Format: ZOO -add archive[.ZOO] file ... The specified files are added to the archive. If all specified files were added without any error, and if this resulted in deletion of a file that was already in the archive, the archive is packed. If packing of the archive occurs, the unpacked archive is renamed to have an extension of ".bak" and the packed archive always appears in the current directory on the current disk. For example, the command "zoo -add qmodem *.com *.00? \doc\q*.doc" would add the following files to archive "qmodem.zoo": all files of the form *.com and *.00? in the current directory, and all files of the form q*.doc in the \doc subdirectory. The archive can be in a different directory or on a different disk. Thus "zoo -add c:\scandals\misc \fortran\ \cobol\*.doc" adds files to the archive "misc.zoo" in the directory "c:\scandals". The files added are: all files in the directory "\fortran" and all *.doc files in the directory "\cobol". If the filespecs given match duplicate filenames, each matching filename is used only once. This is true even if the duplicate filenames refer to different files in different directories. Zoo will not add an archive to itself, nor add the archive's backup to itself, nor add the temporary file {zoo}.@@@ to an archive, nor add any other file that has the same name as these. 2. Extracting Files from an Archive Format: ZOO -extract archive[.ZOO] [file] ... The specified files are extracted from the archive. If no file was specified, all files are extracted from the archive. All extracted files go into the current directory. If a file being extracted would overwrite an already-existing file of the same name, Zoo asks you if you really want to overwrite it. You may answer the question with "y", which means yes, overwrite; or "n", which means no, don't overwrite; or "a", which means assume the answer is "y" for this and all subsequent files. 3. Moving Files to an Archive Format: ZOO -move archive[.ZOO] file ... -Move works just like -add, except that after all files have been added, if no error occurred, the added files are deleted from disk. 4. Testing an Archive Format: ZOO -test archive[.ZOO] This is equivalent to the -extract command, except that extracted files are not saved. If no CRC error or other error occurs during execution of the -test command, this indicates with a high degree of confidence that the archive is not corrupted. 5. Printing Files from an Archive Format: ZOO -print archive[.ZOO] [file] ... This option extracts specified files from the archive and sends the extracted data to standard output, which is normally the screen. The output may be directed to a printer or a disk file using DOS's redirec- tion character ">". Zoo precedes the data of each extracted file by a brief header displaying the name of the file. Error messages are piped to standard output as well. However, if a bad CRC is detected, the bad CRC message is sent both to the screen and to the standard output. 6. Deleting Files in an Archive Format: ZOO -delete archive[.ZOO] file ... The specified files are deleted from the archive, and then the archive is packed to recover space that was occupied by the deleted files. As a safety feature, if the user deletes all files in an archive, no packing of the archive is done and the deleted files may be recovered with the Expert command U (undelete). To delete an archive entirely, use DOS's "del" or "erase" command. 7. Listing Files in an Archive Format: ZOO -list archive[.ZOO] [file] ... This gives a list of the specified files along with information about each file's original size, size as stored in the archive, compression factor, and date. If no files are specified, all files in the archive are listed. If a file would need to be extracted with a version of Zoo higher than the current version, Zoo displays the minimum version number needed. A summary line displays a count of files listed, the total of all original sizes and current sizes, and a net compression factor. The actual size of an archive is always somewhat greater than the total of the current sizes of files in it because of the directory information that is also kept in the archive. 8. Updating an Archive Format: ZOO -update archive[.ZOO] file ... This command is like -add, except that if a file being added is already in the archive, it is added only if the copy being added is newer than the copy already in the archive. The -update commands adds all the files that the -freshen command would add (below) and also adds any files that are not already in the archive. 9. Freshening an Archive Format: ZOO -freshen archive[.ZOO] file ... This command is like -add, except that a file is added only if it is already in the archive, AND if the copy being added is newer than the copy already in the archive. The -freshen command simply brings archived files up to date without adding any files that weren't already in the archive. 10. Adding comments to an Archive Format: ZOO -comment archive[.ZOO] file ... Zoo allows each archived file to have an optional attached comment. Any comment attached to a file is listed when the Novice -list command is given. The -comment command allows comments to be attached, removed, and updated. When invoked with the -comment command, Zoo goes through the specified archive and for each matching file, shows you the comment (if any) and allows you to type a replacement comment. Your choices are: o Type a carriage return alone to leave unchanged any attached comment. o Type "/END" and carriage return to remove any comment attached to the file. o Type a comment of up to 65,535 characters long. Terminate it by typing "/END" by itself on the last line. The new comment will replace any previous comment. For better formatting in listings, keep each line of the comment to 77 characters or less. Since comments are not compressed, they should not be excessively long. It is possible to create a file of comments with a text editor and give it to Zoo as input using DOS's input redirection character "<". In this case, the comments in the file must be in exact sequence. If this input file has fewer comments than Zoo expects, comments for remaining matching files will be left unchanged. If end-of-file is reached before all comments have been accounted for, Zoo simply leaves all remaining files' comments unchanged. End-of-file can be caused by the user typing a control Z interactively or the redirected input being smaller than Zoo expects. Examples: "zoo -comment batch *.bat" shows any comment that may be attached to each *.bat file in the archive "batch.zoo", allows you to type a new comment. Type as many lines as you wish, then type "/END" by itself on a line to terminate the comment. If, however, you want to leave the original comment unchanged, just hit return. You may type control Z at any point to leave all remaining files' comments unchanged. "zoo -comment qmodem *.doc *.00? <qcomment.txt" makes Zoo read new comments from the file "qcomment.txt". For each file matching *.doc and *.00?, Zoo reads data from qcomment.txt and reacts exactly as with interactive input: an empty line (carriage return alone) in "qcomment.txt" leaves the original comment unchanged; "/END" by itself removes the original comment; any other text terminated by "/END" on a separate line replaces a comment. If "qcomment.txt" ends prematurely, all remaining files have their comments left unchanged. EXPERT COMMANDS 1. Adding Files to an Archive Format: ZOO {au}[cfMnPqu] archive[.ZOO] file ... Command characters: a Add files to archive. If "a" is used by itself, each file is added either in compressed or in uncompressed form, whichever is smaller. To add files without compressing them, use the "f" (fast) modifier. If a file with the same name as one being added is already present in the archive, it is marked as deleted. For more information about deleted files, see the D (delete), U (undelete), and P (pack) commands. If the filespecs given match duplicate filenames, each matching filename is used only once. This is true even if the duplicate filenames refer to different files in different directories. Zoo will not add an archive to itself, nor add the archive's backup to itself, nor add the temporary file {zoo}.@@@ to an archive, nor add any other file that has the same name as these. u Update archive. A specified file is added to the archive if a copy of it is already in the archive and the copy being added is newer than the copy already in the archive. Modifiers: c Add comments when adding files. After each file is added, the user is prompted for a comment. If the file being added has replaced a file already in the archive, any comment attached to the replaced file is shown to the user and becomes attached to the newly-added file unless the user changes it. Responses are exac- tly as for the Novice -comment command and the Expert c command: hit carriage return to leave any previous comment unchanged; type "/END" to leave the file without any comment; or type a comment and terminate with "/END" on a line by itself. If the user types control Z in response to a request for a com- ment, Zoo will no longer ask for comments for any subsequent files and their previous comments, if any, will remain unchanged. Note: Since comments for replaced files become automatically attached to corresponding newly-added files, the freshening of an archive with the Novice -freshen command or the Expert au command does not cause loss of comments. f Do a fast add/update by not compressing files as they are added. M Move files to archive. This makes Zoo erase the original files after they have been added to the archive. Files are erased after addition of files to the archive is complete, and after any requested packing of the archive has been done, and only if Zoo detected no errors. n Add new files only. A specified file is added only if it isn't already in the archive. P Pack archive after files have been added. Normally, when Zoo adds a file to an archive and if there was already a copy of the file in the archive, the old copy is marked as being deleted. This does not actually remove the old copy; it exists in the archive and may be undeleted or extracted. Packing the archive permanen- tly removes all deleted files from it and recovers the space they were using. The original archive is never changed during the packing process except that it is renamed to have an extension of ".bak". The packed archive always appears in the current directory on the current disk. q Be quiet. Normally Zoo lists the name of each file as it is added. The q modifier suppresses this. Any error messages are always shown. u Update archive. This has exactly the same effect as when used as a command character (see above). All combinations of the [cfMnPqu] modifiers are valid. The combination of n and u together adds a file to the archive either if the file is not already in the archive, OR if the file is already in the archive but the archived copy is older than the copy being added. Examples: "zoo a pascal *.*" adds all files in the current directory to the ar- chive called "pascal.zoo". If the archive does not already exist, it is created. Each file is added in compressed or uncompressed form, whichever is smaller. "zoo aM pascal *.*" adds the same files and then deletes the original unarchived files. "zoo af pascal *.*" adds the same files without any compression. "zoo aP pascal *.pas" adds all files matching "*.pas" to the archive "pascal.zoo". After all specified files have been added, Zoo packs the archive if it finds any deleted files in it. "zoo aPc pascal *.pas" does exactly the same but also prompt the user for a comment for each file after it is added. "zoo nfP a:/archives/cobol /cobol/" adds all files in the the /cobol subdirectory on the current disk to the archive "cobol.zoo" in the subdirectory "a:/archives", without doing compression. After the files have been added, if Zoo finds any deleted files in the archive, it packs the archive. Packing leaves the original archive unchanged but renamed to have an extension of ".bak". A new packed copy of it appears in the current directory of the current disk. "zoo uq silence silence.com / c:\bin\*.exe" adds the following files to archive "silence.zoo": (a) the file "silence.com"; (b) all files in the root directory; (c) all files in the direc- tory c:\bin that have the extension ".exe". However, since the command u was used, no file is added unless a copy of it is already present in the archive. Because of the q modifier, Zoo does not list names of files as they are added. 2. Extracting Files from an Archive Format: ZOO {ex}[dNoOpq] archive[.ZOO] [file] ... Command characters: x Extract files. Files that were compressed during addition to the archive are decompressed during extraction. All extracted files go into the current directory on the current disk. Not giving a filespec is equivalent to giving "*.*" as the filespec. e Extract files. Synonym for x. Modifiers: d Extract deleted files also. Normally, deleted files are not extracted. The d modifier causes deleted files to be extracted in addition to the normal files. Giving the d modifier twice (e.g. "zoo xdd archive") makes Zoo extract only deleted files. N Send extracted data to Neverland. The data are extracted as without the N modifier but they are not sent to disk. This tests the integrity of an archive. Any error messages will appear on the screen as usual. The absence of any CRC or other error mes- sage indicates with a high degree of confidence that the archive is not corrupted. The q modifier may be used in addition to prevent filenames being listed on the screen. Error messages are never suppressed. If any filespecs are supplied, the "zoo xN ..." command will attempt to extract only the specified files. The integrity of deleted files will not be checked unless the d modifier is also used. Thus to fully check an archive that contains deleted files, use the format "zoo xNd archive". O Overwrite files. Normally, if a file being extracted would over- write an already-existing file of the same name, Zoo asks you if you really want to overwrite it. You may answer the question with "y", which means yes, overwrite; or "n", which means no, don't overwrite; or "a", which means assume the answer is "y" for this and all subsequent files. The O modifier makes Zoo assume that files may always be overwritten. It may not be combined with the N or p modifiers. o The o modifier is equivalent to the O modifier if and only if it is given at least twice. Thus "zoo xoo ..." is equivalent to "zoo xO ...". Otherwise it is ignored. p Pipe extracted data to standard output. Instead of being sent to individual disk files, all extracted data are concatenated and sent to the standard output, which is normally the screen. The output may be redirected to any other destination such as a prin- ter, a communications port or a disk file of your choice, by using the MS-DOS redirection character ">". When thus piping data, Zoo precedes the data of each extracted file by a brief header displaying the name of the file. The q modifier suppresses this header. Error messages are piped to standard output as well. However, if a bad CRC is detected, the bad CRC message is sent both to the screen and to the standard output. q Be quiet. Normally Zoo lists the name of each file as it is extracted. The q modifier suppresses this. (Error messages are always shown.) When used in combination with the p modifier, the q modifier suppresses the filename header preceding each extracted file's data. Examples: "zoo x qmodem" extracts all files from the archive "qmodem.zoo", listing on the screen the name of each file as it is extracted. "zoo xq qmodem" is equivalent to "zoo x qmodem" except that filenames are not listed on the screen as files are extracted. "zoo x qmodem *.com *.00?" extracts all *.com and *.00? files from "qmodem.zoo". "zoo xp zoo *.doc >zoo.txt" extracts all *.doc files from the archive "zoo.zoo" and sends them, concatenated together and with each file being preceded by a header identifying it, to the file "zoo.txt". "zoo xpq zoo *.doc >zoo.txt" does the same except that file data are not preceded by an identifying header. "zoo xNd procomm" extracts all files, including deleted files, from the archive "procomm.zoo" but the extracted data are discarded. Any CRC or other errors will be reported on the screen. The absence of any error message indicates with a high degree of confidence that the archive is not corrupted. 2. Listing Files in an Archive Format: ZOO {lv}[dfv] archive[.ZOO] [file] ... Command characters: l List filenames in archive. A list of all filenames in the archive is presented, including the date and time of each file, its origi- nal size, its current size as stored in the archive, and the per- centage size decrease due to compression (called CF or compression factor). If no filespec is supplied, all files in the archive are shown except deleted files. Optionally, deleted files may be listed; see the description of the d modifier. If a file would need to be extracted with a version of Zoo higher than the current version, Zoo displays the minimum version number needed. A summary line displays a count of files listed, the total of all original sizes and current sizes, and a net compression factor. The actual size of an archive is always somewhat greater than the total of the current sizes of files in it because of the directory information that is also kept in the archive. v Verbose list. Equivalent to l but also shows any comment attached to each file. Version 2.00 of Zoo is expected to allow the user to specify that only the first n lines of each comment be shown. Modifiers: d List deleted files also. Normally, only files that have not been deleted are shown. The d modifier gives a combined display inclu- ding both deleted and not deleted files. Deleted files are marked in the normal listing with "DEL". Giving the the d modifier at least twice (e.g., "zoo ldd archive") displays only deleted files. f Fast listing. The listing gives a multicolumn display of only the filenames, followed by a count of deleted files. Overrrides the v command and the v modifier and prevents any comments from being listed. v Verbose list. Equivalent to the v command. The d modifiers may be separately combined with the f and v modifiers. If the f and v modifiers are used together, f overrrides v. 3. Deleting Files in an Archive Format: ZOO D[Pq1] archive[.ZOO] file ... Command character: D Delete files. The specified files are marked as being deleted. The file remains in the archive, however, and may be listed and extracted. The file does not permanently disappear until the archive is packed (see the P modifier below and the P command elsewhere). If there are multiple instances of the file in the archive, all are deleted; the 1 modifier will prevent this. Modifiers: P Pack archive. After the delete command has taken effect, and if at least one file was deleted, Zoo proceeds to pack the archive. Packing the archive permanently removes all deleted files from the archive. The packed archive always appears in the current disk/directory and the original unpacked archive is renamed to have an extension of ".bak". (To not keep the backup copy, use the P command described elsewhere.) See also the P modifier to the a command. As a safety feature, if the user deletes all files in an archive, no packing is done and the deleted files may be recovered with the U command. To delete an archive entirely, use DOS's "del" or "erase" command. q Be quiet. As files are deleted, their names are normally listed on the screen. The q modifier suppresses this information. Error messages are always shown. 1 One file only. This option (the digit one, not the letter ell) makes Zoo delete at most one file, regardless of how many file- names match the supplied filespecs. This option allows the user to selectively delete only the first of multiple occurrences of the same file. See also the 1 modifier to the U (undelete) command. 4. Undeleting Files in an Archive Format: ZOO U[q1] archive[.ZOO] file ... Command character: U Undelete files. The specified files are marked as being no longer deleted. If there are multiple instances of the same deleted file, all are undeleted; the 1 modifier will prevent this. Modifiers: q Be quiet. As files are undeleted, their names normally are listed on the screen. The q modifier suppresses this information. Error messages are always shown. 1 One file only. This option (the digit one, not the letter ell) makes Zoo undelete at most one file. Regardless of how many files match the filespec(s) supplied, Zoo stops after undeleting one. Every time a file is added to an archive, any (one) previous archived file having the same name is marked deleted. If the same file is repeatedly added to an archive, multiple deleted instances of the file appear in the archive. Any one of these may be selectively extracted by careful and patient successive use of the 1 option combined with the U (undelete) and D (delete) commands. 5. Adjusting the Timestamp of an Archive Format: ZOO T[q] archive[.ZOO] Command character: T Zoo normally tries to always keep time and date stamp of archives to be the same as that of the newest file in the archive. The T command allows this to be done manually at any time. An informative message is given. The T command is useful if you have downloaded an archive via telecommunications and you want to fix its timestamp to reflect the age of the newest file in the archive. Modifier: q The q modifier suppresses the informative message. 6. Packing an Archive Format: ZOO P[EPq] archive[.ZOO] Command character: P When Zoo adds a file to an archive, any previous instance of that file in the archive is marked as deleted but remains in the ar- chive. The P command packs an archive and permanently removes all deleted files from it. Unless the user specifies otherwise, the original archive is renamed to have the extension ".bak" and remains otherwise unchanged. The packed archive always appears on the current disk/directory. Files appearing in the packed archive will retain any attached comments. Floppy disk users who pack an archive that takes up more than half the disk space should keep the original archive on a disk differ- ent from the current disk. The packed copy of the archive will appear on the current disk. Zoo archives can pick up garbage at the end because of Xmodem file transfers or due to being stored on certain computer systems that round up file size to a power of two. The P command will truncate such an archive to its proper size. If packing an archive would result in nothing being left in the archive, the packing leaves the archive unchanged. Modifiers: E When an archive is packed, the original copy of the archive is normally not deleted but simply renamed to have the extension ".bak". For example, packing "apple.zoo" will give a new packed archive called "apple.zoo", and a backup copy "apple.bak" that is identical to the original archive. The user may specify deletion of the backup copy with the E modifier. P Normally, if Zoo finds that a backup copy of an archive already exists, it will refuse to pack the archive again, for that would mean losing the old backup copy. The P forces Zoo to proceed with packing and delete the old backup copy. For example, suppose both "london.zoo" and "london.bak" exist. Zoo will give an error message in response to the command "zoo P london"; however, it will pack the archive if the command "zoo PP london" is given. When packing is done, the packed archive is initially created as a temporary file called "{zoo}.@@@". After successful packing, this temporary file is renamed to the name of the original archive while the original archive is renamed to have an extension of ".bak". If archive packing is aborted for any reason, the temporary file "{zoo}.@@@" is left in the directory. This file also appears if, after packing is completed, Zoo is unable to rename this file to the name of the original archive. DISK SPACE CONSIDERATIONS When Zoo is adding files to an archive, it gives an error message and exits as soon as disk space is too low to add the next specified file. When Zoo is extracting files from an archive, however, it attempts to go on as long as it can. If a file being extracted would exceed the space avail- able on disk, Zoo gives an error message but goes on to attempt to extract the next matching file. It aborts entirely only if the disk becomes completely full. Archive packing requires enough disk space to create a new copy of the archive. The archive to be packed may be kept on a disk other than the current disk. The packed archive appears on the current disk. INTERRUPTING WITH CONTROL C Zoo may be interrupted with control C at any time. Aborting operation with control C should not result in any damaged files. Rapid repeated hitting of control C could potentially leave files in an inconsistent state, although it has not been observed to happen. (If you hit control C once and Zoo doesn't seem to notice, it probably missed it; it should be safe to wait about five seconds and try again.) Because of the way MS-DOS handles user interrupts, it was found necessary, to preserve archive integrity, that Zoo disable break status (shown and set by the DOS "break" command). Zoo 1.03N does not restore break status to its original value when it exits; version 2.00 is expected to do so. EXIT STATUS Zoo returns an exit status of 0 if no errors occurred, and 1 if an error occurred or if no files matched when listing an archive. This exit status may be tested in a batch file using the DOS "if errorlevel 1 goto ..." statement or from an executing parent process using DOS system call 4D hexadecimal. ARCHIVE INTEGRITY When Zoo adds a file to an archive, it is always appended to the end of the archive, so a system crash should not normally affect the integrity of the archive. If Zoo is interrupted while adding a file to an archive, the added file may not show up as being in the archive but some or all of its data will have been appended to the archive. The P (pack) command will restore the archive to its original size. When Zoo appends a file to an archive and a previous instance of the same file exists in the archive, the previous instance is marked deleted. This involves a direct (random) access write to the archive. In theory, if there were a system crash while the disk hardware was writing an updated directory entry in an archive, damage to the archive could occur. In practice, this is likely to be very rare. It is recommended that backup copies be always kept of valuable archives. CONVERSION FROM OTHER FORMATS TO ZOO FORMAT The batch program ATOZ.BAT can help you convert a subdirectory full of files in another format (such as *.LBR and *.ARC) to Zoo format. See ATOZ.DOC for instructions. Due to differences between the batch languages of DOS 3.x and DOS 2.x, Atoz 1.00 works only with DOS 2.x. VERSION COMPATIBILITY Zoo 1.10 can add information to an archive in the form of attached comments that earlier versions of Zoo cannot interpret. Earlier versions of Zoo will list and extract files from version 1.10 archives and delete and undelete files in them. But to avoid any loss of information, earlier versions of Zoo will refuse to modify version 1.10 archives in any other way. Instead, the following message will be given: "Version 1.10 of Zoo is needed to fully manipulate this archive." VERSION 2.00 Version 2.00, when released, is expected to have the following additional features: 1. Filename listings will be alphabetized. 2. Source code in (fairly) generic *NIX-compatible C will be available. 3. A listing of files in the archive will show the first N lines of the comment for each file, N being specified by the user. 4. Multiple instances of the same file in an archive will be properly handled, each being identified by a version number. 5. It will be possible to execute archived programs. Zoo will directly extract the program into memory and execute it rather than creating a temporary file first. ACKNOWLEDGMENTS Zoo uses a dynamic Lempel-Ziv-Welch data compression procedure adapted from assembly routines written by Tom Pfau. Ball State University and its Department of Computer Science provided me with a working environment, software, and other support. FEEDBACK Bug reports and other feedback should be directed to me at these electronic mail addresses. GEnie: DHESI People/Link: OLS806 Arpanet/CSnet: dhesi%bsu@csnet-relay.ARPA UUCP: ...!seismo!csnet-relay.ARPA!bsu!dhesi Telephone calls are not encouraged but if absolutely necessary, try (317) 285-8641 during working hours, Eastern Standard Time.