Provided by: zoo_2.10-23_i386 bug

NAME

       zoo - manipulate archives of files in compressed form

SYNOPSIS

       zoo {acfDeghHlLPTuUvVx}[aAcCdEfghImMnNoOpPqSu1:/.@n+-=] archive [file]
       ...
       zoo -command archive [file] ...
       zoo h

DESCRIPTION

       Zoo is used to create and maintain collections of files in compressed
       form.  It uses a Lempel-Ziv compression algorithm that gives space
       savings in the range of 20% to 80% depending on the type of file data.
       Zoo can store and selectively extract multiple generations of the same
       file.  Data can be recovered from damaged archives by skipping the
       damaged portion and locating undamaged data with the help of fiz(1).

       This documentation is for version 2.1.  Changes from previous versions
       are described in the section labelled CHANGES.

       The command zoo h gives a summary of commands.  Extended multiscreen
       help can be obtained with zoo H.

       Zoo will not add an archive to itself, nor add the archive's backup
       (with .bak extension to the filename) to the archive.

       Zoo has two types of commands:  Expert commands, which consist of one
       command letter followed by zero or more modifier characters, and Novice
       commands, which consist of a hyphen (`-') followed by a command word
       that may be abbreviated.  Expert commands are case-sensitive but Novice
       commands are not.

       When zoo adds a file to an existing archive, the default action is to
       maintain one generation of each file in an archive and to mark any
       older generation as deleted.  A limit on the number of generations to
       save can be specified by the user for an entire archive, or for each
       file individually, or both.  Zoo deletes a stored copy of an added file
       if necessary to prevent the number of stored generations from exceeding
       the user-specified limit.

       Deleted files may be later undeleted.  Archives may be packed to
       recover space occupied by deleted files.

       All commands assume that the archive name ends with the characters .zoo
       unless a different extension is supplied.

       Novice commands

       Novice commands may be abbreviated to a hyphen followed by at least one
       command character.  Each Novice command works in two stages.  First,
       the command does its intended work.  Then, if the result was that one
       or more files were deleted in the specified archive, the archive is
       packed.  If packing occurs, the original unpacked archive is always
       left behind with an extension of .bak.

       No Novice command ever stores the directory prefix of a file.

       The Novice commands are as follows.

       -add    Adds the specified files to the archive.

       -freshen
              Adds a specified file to the archive if and only if an older
              file by the same name already exists in the archive.

       -delete
              Deletes the specified files from the archive.

       -update
              Adds a specified file to the archive either:  if an older file
              by the same name already exists in the archive or:  if a file by
              the same name does not already exist in the archive.

       -extract
              Extracts the specified files from the archive.  If no file is
              specified all files are extracted.

       -move  Equivalent to -add except that source files are deleted after
              addition.

       -print Equivalent to -extract except that extracted data are sent to
              standard output.

       -list  Gives information about the specified archived files including
              any attached comments.  If no files are specified all files are
              listed.  Deleted files are not listed.

       -test  Equivalent to -extract except that the extracted data are not
              saved but any errors encountered are reported.

       -comment
              Allows the user to add or update comments attached to archived
              files.  When prompted, the user may:  type a carriage return to
              skip the file, leaving any current comment unchanged;  or type a
              (possibly null) comment of up to 32,767 characters terminated by
              /end (case-insensitive) on a separate line;  or type the end-of-
              file character (normally control D) to skip all remaining files.

       -delete
              Deletes the specified files.

       The correspondence between Novice and Expert commands is as follows.

       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 to standard output   xp
       -delete    delete files from archive          DP
       -list      list archive contents              VC
       -update    add new or newer files             aunP:
       -freshen   by add newer files                 auP:
       -comment   add comments to files              c

       Expert commands

       The general format of expert commands is:

       zoo {acfDeghHlLPTuUvVx}[aAcCdEfghImMnNoOpPqSu1:/.@n+-=] archive [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.

       Files are added to an archive with the command:

       zoo {au}[cfhIMnPqu:+-] archive [file] ...

       Command characters are:

       a      Add each specified file to archive.  Any already-archived copy
              of the file is deleted if this is necessary to avoid exceeding
              the user-specified limit on the number of generations of the
              file to maintain in the archive.

       u      Do an update of the archive.  A specified file is added to the
              archive only if a copy of it is already in the archive and the
              copy being added is newer than the copy already in the archive.

       The following modifiers are specific to these commands.

       M      Move files to archive.  This makes zoo delete (unlink) the
              original files after they have been added to the archive.  Files
              are deleted after addition of all 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.

       h      Use the high performance compression algorithm. This option may
              be used with either the add (a) or filter (f) commands to gain
              extra compression at the expense of using somewhat more
              processor time. Extracting files compressed with the method is
              usually slightly faster than those saved with the default
              method.

       P      Pack archive after files have been added.

       u      Applied to the a command, this modifier makes it behave
              identically to the u command.

              The combination of the n modifier with the u modifier or u
              command causes addition of 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.

       :      Do not store directory names.  In the absence of this modifier
              zoo stores the full pathname of each archived file.

       I      Read filenames to be archived from standard input.  Zoo will
              read its standard input and assume that each line of text
              contains a filename.  Under AmigaDOS and the **IX family, the
              entire line is used.  Under MS-DOS and VAX/VMS, zoo assumes that
              the filename is terminated by a blank, tab, or newline; thus it
              is permissible for the line of text to contain more than one
              field separated by white space, and only the first field will be
              used.

              Under the **IX family of operating systems, zoo can be used as
              follows in a pipeline:

                 find . -print | zoo aI sources

            If the I modifier is specified, no filenames may be supplied on
            the command line itself.

       +,-    These modifiers take effect only if the a command results in the
              creation of a new archive.  + causes any newly-created archive
              to have generations enabled.  - is provided for symmetry and
              causes any newly-created archive to have generations disabled;
              this is also the default if neither + nor - is specified.

       Files are extracted from an archive with the command:

       zoo {ex}[dNoOpqS./@] archive [file] ...

       The e and x commands are synonymous.  If no file was specified, all
       files are extracted from the archive.

       The following modifiers are specific to the e and x commands:

       N      Do not save extracted data but report any errors encountered.

       O      Overwrite files.  Normally, 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.  The O modifier makes
              zoo assume that files may always be overwritten.  Neither
              answering the question affirmatively nor using O alone will
              cause read-only files to be overwritten.

              On **IX systems, however, doubling this modifier as OO will
              force zoo to unconditionally overwrite any read-protected files
              with extracted files if it can do so.

              The O, N, and p modifiers are mutually exclusive.

       S      Supersede newer files on disk with older extracted files.
              Unless this modifier is used, zoo will not overwrite a newer
              existing file with an older extracted file.

       o      This is equivalent to the O modifier if and only if it is given
              at least twice.  It is otherwise ignored.

       p      Pipe extracted data to standard output.  Error messages are
              piped to standard output as well.  However, if a bad CRC is
              detected, an error message is sent both to standard error and to
              standard output.

       /      Extract to original pathname.  Any needed directories must
              already exist.  In the absence of this modifier all files are
              extracted into the current directory.  If this modifier is
              doubled as //, required directories need not exist and are
              created if necessary.

       The management of multiple generations of archived files is done with
       the commands:

       zoo gl[Aq]{+-=}number archive files ..
       zoo gc[q]{+-=}number archive files ..
       zoo gA[q]- archive
       zoo gA[q]+ archive

       The first form, gl, adjusts the generation limit of selected files by
       the specified value.  If the form =n is used, where n is a decimal
       number, this sets the generation limit to the specified value.  If + or
       - are used in placed of = the effect is to increment or decrement the
       generation limit by the specified value.  For example, the command

            zoo gl=5 xyz :

       sets the generation limit of each file in the archive xyz.zoo to a
       value of 5.  The command

            zoo gl-3 xyz :

       decrements the generation limit of each file in the archive to 3 less
       than it currently is.

       If the A modifier is used, the archive-wide generation limit is
       adjusted instead.

       The number of generations of a file maintained in an archive is limited
       by the file generation limit, or the archive generation limit,
       whichever is lower.  As a special case, a generation limit of 0 stands
       for no limit.  Thus the default file generation limit of 0 and archive
       generation limit of 3 limits the number of generations of each file in
       a newly-created archive to three.

       The generation limit specified should be in the range 0 through 15;
       any higher numbers are interpreted modulo 16.

       The second form of the command, using gc, adjusts the generation count
       of selected files.  Each file has a generation count of 1 when it is
       first added to an archive.  Each time a file by the same name is added
       again to an archive, it receives a generation count that is one higher
       than the highest generation count of the archived copy of the file.
       The permissible range of generation counts is 1 through 65535.  If
       repeated manipulations of an archive result in files having very high
       generation counts, they may be set back to lower numbers with the gc
       command.  The syntax of the command is analogous to the syntax of the
       gl command, except that the A modifier is not applicable to the gc
       command.

       The third form, gA-, disables generations in an archive.  Generations
       are off when an archive is first created, but may be enabled with the
       fourth form of the command, gA+.  When generations are disabled in an
       archive, zoo will not display generation numbers in archive listings or
       maintain multiple generations.  Generations can be re-enabled at any
       time, though manipulation of an archive with repeated interspersed gA-
       and gA+ commands may result in an archive whose behavior is not easily
       understandable.

       Archived files are listed with the command:

       zoo {lLvV}[aAcCdfgmqvV@/1+-] archive[.zoo] [file] ...

       l      Information presented includes the date and time of each file,
              its original and current (compressed) sizes, and the percentage
              size decrease due to compression (labelled CF or compression
              factor).  If a file was added to the archive in a different
              timezone, the difference between timezones is shown in hours as
              a signed number.  As an example, if the difference is listed as
              +3, this means that the file was added to the archive in a
              timezone that is 3 hours west of the current timezone.  The file
              time listed is, however, always the original timestamp of the
              archived file, as observed by the user who archived the file,
              expressed as that user's local time.  (Timezone information is
              stored and displayed only if the underlying operating system
              knows about timezones.)

              If no filename is supplied all files are listed except deleted
              files.

              Zoo selects which generation(s) of a file to list according to
              the following algorithm.

              If no filename is supplied, only the latest generation of each
              file is listed.  If any filenames are specified, and a
              generation is specified for an argument, only the requested
              generation is listed.  If a filename is specified ending with
              the generation character (`:' or `;'), all generations of that
              file are listed.  Thus a filename argument of the form zoo.c
              will cause only the latest generation of zoo.c to be listed;  an
              argument of the form zoo.c:4 will cause generation 4 of zoo.c to
              be listed;  and an argument of the form zoo.c: or zoo.c:* will
              cause all generations of zoo.c to be listed.

       L      This is similar to the l command except that all supplied
              arguments must be archives and all non-deleted generations of
              all files in each archive appear in the listing.

              On **IX systems, on which the shell expands arguments, if
              multiple archives are to be listed, the L command must be used.
              On other systems (VAX/VMS, AmigaDOS, MSDOS) on which wildcard
              expansion is done internally by zoo, wildcards may be used in
              the archive name, and a multiple archive listing obtained, using
              the l command.

       v      This causes any comment attached to the archive to be listed in
              addition to the other information.

       V      This causes any comment attached to the archive and also any
              comment attached to each file to be listed.

              Both the V and v command characters can also be used as
              modifiers to the l and L commands.

       In addition to the general modifiers described later, the following
       modifiers can be applied to the archive list commands.

       a      This gives a single-line format containing both each filename
              and the name of the archive, sorted by archive name.  It is
              especially useful with the L command, since the result can be
              further sorted on any field to give a master listing of the
              entire contents of a set of archives.

       A      This causes any comment attached to the archive to be listed.

       g      This modifier causes file generation information to be listed
              about the archive.  For each file listed, the user-specified
              generation limit, if any, is listed.  For example, `3g' for a
              file means that the user wants no more than three generations of
              the file to be kept.  In archives created by older versions of
              zoo, the listing will show `-g', meaning that no generation
              information is kept and multiple generations of the file are not
              being maintained.

              In addition to the generation information for each file, the
              archive-wide generation limit, if any, is shown at the end of
              the listing.  If generations have been disabled by the user,
              this is so indicated, for example:

                 Archive generation limit is 3 (generations off).

            For more information about generations see the description of the
            g command.

       m      This modifier is currently applicable to **IX systems only.  It
              causes the mode bits (file protection code) of each file to be
              listed as a three-digit octal number.  Currently zoo preserves
              only the lowest nine mode bits.  Their meanings are as described
              in the **IX documentation for the chmod(1) command.

       C      This modifier causes the stored cyclic redundancy code (CRC) for
              each archived file to be shown as a four-digit hexadecimal
              number.

       1      This forces one filename to be listed per line.  It is most
              useful in combination with the f modifier.

       /      This forces any directory name to be always listed, even in fast
              columnized listings that do not normally include any directory
              names.

       +,-    The - modifier causes trailing generation numbers to be omitted
              from filenames.  The + modifier causes the trailing generation
              numbers to be shown, which is also the default if neither - nor
              + is specified.

       Files may be deleted and undeleted from an archive with the following
       commands:

       zoo {DU}[Pq1] archive file ...

       The D command deletes the specified files and the U command undeletes
       the specified files.  The 1 modifier (the digit one, not the letter
       ell) forces deletion or undeletion of at most one file.  If multiple
       instances of the same file exist in an archive, use of the 1 modifier
       may allow selective extraction of one of these.

       Comments may be added to an archive with the command:

       zoo c[A] archive

       Without the modifier A, this behaves identically to the -comment
       command.  With the modifier A, the command serves to add or update the
       comment attached to the archive as a whole.  This comment may be listed
       with the lA, LA, v, and V commands.  Applying the cA command to an
       archive that was created with an older version of zoo will result in an
       error message requesting that the user first pack the archive with the
       P command.  This reorganizes the archive and creates space for the
       archive comment.

       The timestamp of an archive may be adjusted with the command:

       zoo T[q] archive

       Zoo normally attempts to maintain the timestamp of an archive to
       reflect the age of the newest file stored in it.  Should the timestamp
       ever be incorrect it can be fixed with the T command.

       An archive may be packed with the command:

       zoo P[EPq] archive

       If the backup copy of the archive already exists, zoo will refuse to
       pack the archive unless the P modifier is also given.  The E modifier
       causes zoo not to save a backup copy of the original archive after
       packing.  A unique temporary file in the current directory is used to
       initially hold the packed archive.  This file will be left behind if
       packing is interrupted or if for some reason this file cannot be
       renamed to the name of the original archive when packing is complete.

       Packing removes any garbage data appended to an archive because of
       Xmodem file transfer and also recovers any wasted space remaining in an
       archive that has been frequently updated or in which comments were
       replaced.  Packing also updates the format of any archive that was
       created by an older version of zoo so that newer features (e.g.
       archive-wide generation limit, archive comment) become fully available.

       Zoo can act as a pure compression or uncompression filter, reading from
       standard input and writing to standard output.  This is achieved with
       the command:

       zoo f{cu}[h]

       where c specifies compression, u specifies uncompression, and h used in
       addition requests the high-performance compression be used.  A CRC
       value is used to check the integrity of the data.  The compressed data
       stream has no internal archive structure and contains multiple files
       only if the input data stream was already structured, as might be
       obtained, for example, from tar or cpio.

        Modem transfers can be speeded up with these commands:

                 zoo fc < file | sz ...  rz | zoo fu > file

       General modifiers

       The following modifiers are applicable to several commands:

       c      Applied to the a and u commands, this causes the user to be
              prompted for a comment for each file added to the archive.  If
              the file being added has replaced, or is a newer generation of,
              a file already in the archive, any comment attached to that file
              is shown to the user and becomes attached to the newly-added
              file unless the user changes it.  Possible user responses are as
              described for the -comment command.  Applied to the archive list
              command l, the c modifier causes the listing of any comments
              attached to archived files.

        .     In conjunction with / or // this modifier causes any extracted
              pathname beginning with `/' to be interpreted relative to the
              current directory, resulting in the possible creation of a
              subtree rooted at the current directory.  In conjunction with
              the command P the .  modifier causes the packed archive to be
              created in the current directory.  This is intended to allow
              users with limited disk space but multiple disk drives to pack
              large archives.

       d      Most commands that act on an archive act only on files that are
              not deleted.  The d modifier makes commands act on both normal
              and deleted files.  If doubled as dd, this modifier forces
              selection only of deleted files.

       f      Applied to the a and u commands, the f modifier causes fast
              archiving by adding files without compression.  Applied to l it
              causes a fast listing of files in a multicolumn format.

       q      Be quiet.  Normally zoo lists the name of each file and what
              action it is performing.  The q modifier suppresses this.  When
              files are being extracted to standard output, the q modifier
              suppresses the header preceding each file.  When archive
              contents are being listed, this modifier suppresses any header
              and trailer.  When a fast columnized listing is being obtained,
              this modifier causes all output to be combined into a single set
              of filenames for all archives being listed.

              When doubled as qq, this modifier suppresses WARNING messages,
              and when tripled as qqq, ERROR messages are suppressed too.
              FATAL error messages are never suppressed.

       Recovering data from damaged archives

       The @ modifier allows the user to specify the exact position in an
       archive where zoo should extract a file from, allowing damaged portions
       of an archive to be skipped.  This modifier must be immediately
       followed by a decimal integer without intervening spaces, and possibly
       by a comma and another decimal integer, giving a command of the form
       l@m or l@m,n (to list archive contents) or x@m or x@m,n (to extract
       files from an archive).  Listing or extraction begin at position m in
       the archive.  The value of m must be the position within the archive of
       an undamaged directory entry.  This position is usually obtained from
       fiz(1) version 2.0 or later.

       If damage to the archive has shortened or lengthened it, all positions
       within the archive may be changed by some constant amount.  To
       compensate for this, the value of n may be specified.  This value is
       also usually obtained from fiz(1).  It should be the position in the
       archive of the file data corresponding to the directory entry that has
       been specified with m.  Thus if the command x@456,575 is given, it will
       cause the first 456 bytes of the archive to be skipped and extraction
       to begin at offset 456;  in addition, zoo will attempt to extract the
       file data from position 575 in the archive instead of the value that is
       found in the directory entry read from the archive.  For example, here
       is some of the output of fiz when it acts on a damaged zoo archive:

       ****************
           2526: DIR  [changes] ==>   95
           2587: DATA
       ****************
           3909: DIR  [copyright] ==> 1478
           3970: DATA
           4769: DATA
       ****************

       In such output, DIR indicates where fiz found a directory entry in the
       archive, and DATA indicates where fiz found file data in the archive.
       Filenames located by fiz are enclosed in square brackets, and the
       notation "==>   95" indicates that the directory entry found by fiz at
       position 2526 has a file data pointer to position 95.  (This is clearly
       wrong, since file data always occur in an archive after their directory
       entry.)  In actuality, fiz found file data at positions 2587, 3970, and
       4769.  Since fiz found only two directory entries, and each directory
       entry corresponds to one file, one of the file data positions is an
       artifact.

       In this case, commands to try giving to zoo might be x@2526,2587
       (extract beginning at position 2526, and get file data from position
       2587), x@3090,3970 (extract at 3090, get data from 3970) and
       x@3909,4769 (extract at 3909, get data from 4769).  Once a correctly-
       matched directory entry/file data pair is found, zoo will in most cases
       synchronize with and correctly extract all files subsequently found in
       the archive.  Trial and error should allow all undamaged files to be
       extracted.  Also note that self-extracting archives created using sez
       (the Self-Extracting Zoo utility for MS-DOS), which are normally
       executed on an MS-DOS system for extraction, can be extracted on non-
       MSDOS systems using zoo's damaged-archive recovery method using the @
       modifier.

       Wildcard handling

       Under the **IX family of operating systems, the shell normally expands
       wildcards to a list of matching files.  Wildcards that are meant to
       match files within an archive must therefore be escaped or quoted.
       When selecting files to be added to an archive, wildcard conventions
       are as defined for the shell.  When selecting files from within an
       archive, wildcard handling is done by zoo as described below.

       Under MS-DOS and AmigaDOS, quoting of wildcards is not needed.  All
       wildcard expansion of filenames is done by zoo, and wildcards inside
       directory names are expanded only when listing or extracting files but
       not when adding them.

       The wildcard syntax interpreted by zoo is limited to the following
       characters.

       *      Matches any sequence of zero or more characters.

       ?      Matches any single character.

              Arbitrary combinations of * and ?  are allowed.

       /      If a supplied pattern contains a slash anywhere in it, then the
              slash separating any directory prefix from the filename must be
              matched explicitly.  If a supplied pattern contains no slashes,
              the match is selective only on the filename.

       c-c    Two characters separated by a hyphen specify a character range.
              All filenames beginning with those characters will match.  The
              character range is meaningful only by itself or preceded by a
              directory name.  It is not specially interpreted if it is part
              of a filename.

       : and ;
              These characters are used to separate a filename from a
              generation number and are used when selecting specific
              generations of archived files.  If no generation character is
              used, the filename specified matches only the latest generation
              of the file.  If the generation character is specified, the
              filename and the generation are matched independently by zoo's
              wildcard mechanism.  If no generation is specified following the
              : or ; character, all generations of that file will match.  As a
              special case, a generation number of 0 matches only the latest
              generation of a file, while ^0 matches all generations of a file
              except the latest one.  If no filename is specified preceding
              the generation character, all filenames will match.  As a
              corollary, the generation character by itself matches all
              generations of all files.

       MS-DOS users should note that zoo does not treat the dot as a special
       character, and it does not ignore characters following an asterisk.
       Thus * matches all filenames; *.*  matches filenames containing a dot;
       *_* matches filenames containing an underscore;  and *z matches all
       filenames that end with the character z, whether or not they contain a
       dot.

       Usage hints

       The Novice command set in zoo is meant to provide an interface with
       functionality and format that will be familiar to users of other
       similar archive utilities.  In keeping with this objective, the Novice
       commands do not maintain or use any subdirectory information or allow
       the use of zoo's ability to maintain multiple generations of files.
       For this reason, users should switch to exclusively using the Expert
       commands as soon as possible.

       Although the Expert command set is quite large, it should be noted that
       in almost every case, all legal modifiers for a command are fully
       orthogonal.  This means that the user can select any combination of
       modifiers, and when they act together, they will have the intuitively
       obvious effect.  Thus the user need only memorize what each modifier
       does, and then can combine them as needed without much further thought.

       For example, consider the a command which is used to add files to an
       archive.  By itself, it simply adds the specified files.  To cause only
       already-archived files to be updated if their disk copies have been
       modified, it is only necessary to add the u modifier, making the
       command au.  To cause only new files (i.e., files not already in the
       archive) to be added, the n modifier is used to create the command an.
       To cause both already-archived files to be updated and new files to be
       added, the u and n modifiers can be used together, giving the command
       aun.  Since the order of modifiers is not significant, the command
       could also be anu.

       Further, the c modifier can be used to cause zoo to prompt the user for
       a comment to attach to each file added.  And the f modifier can cause
       fast addition (addition without compression).  It should be obvious
       then that the command auncf will cause zoo to update already-archived
       files, add new files, prompt the user for comments, and do the addition
       of files without any compression.  Furthermore, if the user wishes to
       move files to the archive, i.e., delete the disk copy of each file
       after it is added to the archive, it is only necessary to add the M
       modifier to the command, so it becomes auncfM.  And if the user also
       wishes to cause the archive to be packed as part of the command, thus
       recovering space from any files that are replaced, the command can be
       modified to auncfMP by adding the P modifier that causes packing.

       Similarly, the archive listing commands can be built up by combining
       modifiers.  The basic command to list the contents of an archive is l.
       If the user wants a fast columnized listing, the f modifier can be
       added to give the lf command.  Since this listing will have a header
       giving the archive name and a trailer summarizing interesting
       information about the archive, such as the number of deleted files, the
       user may wish to "quieten" the listing by suppressing these;  the
       relevant modifier is q, which when added to the command gives lfq.  If
       the user wishes to see the **IX mode (file protection) bits, and also
       information about multiple generations, the modifiers m (show mode
       bits) and g (show generation information) can be added, giving the
       command lfqmg.  If the user also wishes to see an attached archive
       comment, the modifier A (for archive) will serve.  Thus the command
       lfqmgA will give a fast columnized listing of the archive, suppressing
       any header and trailer, showing mode bits and generation information,
       and showing any comment attached to the archive as a whole.  If in
       addition individual comments attached to files are also needed, simply
       append the c modifier to the command, making it lfqmgAc.  The above
       command will not show any deleted files, however;  to see them, use the
       d modifier, making the command lfqmgAcd (or double it as in lfqmgAcdd
       if only the deleted files are to be listed).  And if the user also
       wishes to see the CRC value for each file being listed, the modifier C
       will do this, as in the command lfqmgAcdC, which gives a fast
       columnized listing of all files, including deleted files, showing any
       archive comment and file comments, and file protection codes and
       generation information, as well as the CRC value of each file.

       Note that the above command lfqmgAcdC could also be abbreviated to
       VfqmgdC because the command V is shorthand for lcA (archive listing
       with all comments shown).  Similarly the command v is shorthand for lA
       (archive listing with archive comment shown).  Both V and v can be used
       as modifiers to any of the other archive listing commands.

       Generations

       By default, zoo assumes that only the latest generation of a specified
       file is needed.  If generations other than the latest one need to be
       selected, this may be done by specifying them in the filename.  For
       example, the name stdio.h would normally refer to the latest generation
       of the file stdio.h stored in a zoo archive.  To get an archive listing
       showing all generations of stdio.h in the archive, the specification
       stdio.h:* could be used (enclosed in single quotes if necessary to
       protect the wildcard character * from the shell).  Also, stdio.h:0
       selects only the latest generation of stdio.h, while stdio.h:^0 selects
       all generations except the latest one.  The : character here separates
       the filename from the generation number, and the character * is a
       wildcard that matches all possible generations.  For convenience, the
       generation itself may be left out, so that the name stdio.h: (with the
       : but without a generation number or a wildcard) matches all
       generations exactly as stdio.h:* does.

       If a generation is specified but no filename is present, as in :5, :*,
       or just :, all filenames of the specified generation will be selected.
       Thus :5 selects generation 5 of each file, and :* and : select all
       generations of all files.

       It is important to note that zoo's idea of the latest generation of a
       file is not based upon searching the entire archive.  Instead, whenever
       zoo adds a file to an archive, it is marked as being the latest
       generation.  Thus, if the latest generation of a file is deleted, then
       no generation of that file is considered the latest any more.  This can
       be surprising to the user.  For example, if an archive already contains
       the file stdio.h:5 and a new copy is added, appearing in the archive
       listing as stdio.h:6, and then stdio.h:6 is deleted, the remaining copy
       stdio.h:5 will no longer be considered to be the latest generation, and
       the file stdio.h:5, even if undeleted, will no longer appear in an
       archive listing unless generation 5 (or every generation) is
       specifically requested.  This behavior will likely be improved in
       future releases of zoo.

FILES

       xXXXXXX - temporary file used during packing
       archive_name.bak - backup of archive

SEE ALSO

       compress(1), fiz(1)

BUGS

       When files are being added to an archive on a non-MS-DOS system, it is
       possible for zoo to fail to detect a full disk and hence create an
       invalid archive.  This bug will be fixed in a future release.

       Files with generation counts that wrap around from 65535 to 1 are not
       currently handled correctly.  If a file's generation count reaches a
       value close to 65535, it should be manually set back down to a low
       number.  This may be easily done with a command such as gc-65000, which
       subtracts 65000 from the generation count of each specified file.  This
       problem will be fixed in a future release.

       Although zoo on **IX systems preserves the lowest nine mode bits of
       regular files, it does not currently do the same for directories.

       Currently zoo's handling of the characters : and ; in filenames is not
       robust, because it interprets these to separate a filename from a
       generation number.  A quoting mechanism will eventually be implemented.

       Standard input cannot be archived nor can a created archive be sent to
       standard output.  Spurious error messages may appear if the filename of
       an archive is too long.

       Since zoo never archives any file with the same name as the archive or
       its backup (regardless of any path prefixes), care should be taken to
       make sure that a file to be archived does not coincidentally have the
       same name as the archive it is being added to.  It usually suffices to
       make sure that no file being archived is itself a zoo archive.
       (Previous versions of zoo sometimes tried to add an archive to itself.
       This bug now seems to be fixed.)

       Only regular files are archived; devices and empty directories are not.
       Support for archiving empty directories and for preserving directory
       attributes is planned for the near future.

       Early versions of MS-DOS have a bug that prevents "." from referring to
       the root directory;  this leads to anomalous results if the extraction
       of paths beginning with a dot is attempted.

       VAX/VMS destroys case information unless arguments are enclosed in
       double quotes.  For this reason if a command given to zoo on a VAX/VMS
       system includes any uppercase characters, it must be enclosed in double
       quotes.  Under VAX/VMS, zoo does not currently restore file timestamps;
       this will be fixed as soon as I figure out RMS extended attribute
       blocks, or DEC supplies a utime() function, whichever occurs first.
       Other VMS bugs, related to file structures, can often be overcome by
       using the program bilf.c that is supplied with zoo.

       It is not currently possible to create a zoo archive containing all zoo
       archives that do not contain themselves.

DIAGNOSTICS

       Error messages are intended to be self-explanatory and are divided into
       three categories.  WARNINGS are intended to inform the user of an
       unusual situation, such as a CRC error during extraction, or
       -freshening of an archive containing a file newer than one specified on
       the command line.  ERRORS are fatal to one file, but execution
       continues with the next file if any.  FATAL errors cause execution to
       be aborted.  The occurrence of any of these causes an exit status of 1.
       Normal termination without any errors gives an exit status of 0.
       (Under VAX/VMS, however, to avoid an annoying message, zoo always exits
       with an error code of 1.)

COMPATIBILITY

       All versions of zoo on all systems are required to create archives that
       can be extracted and listed with all versions of zoo on all systems,
       regardless of filename and directory syntax or archive structure;
       furthermore, any version of zoo must be able to fully manipulate all
       archives created by all lower-numbered versions of zoo on all systems.
       So far as I can tell, this upward compatibility (all manipulations) and
       downward compatibility (ability to extract and list) is maintained by
       zoo versions up to 2.01.  Version 2.1 adds the incompatibility that if
       high-performance compression is used, earlier versions cannot extract
       files compressed with version 2.1.

CHANGES

       Here is a list of changes occurring from version 1.50 to version 2.01.
       In parentheses is given the version in which each change occurred.

       -      (1.71) New modifiers to the list commands permit optional
              suppression of header and trailer information, inclusion of
              directory names in columnized listings, and fast one-column
              listings.

       -      (1.71) Timezones are handled.

       -      (1.71) A bug was fixed that had made it impossible to
              individually update comments for a file whose name did not
              correspond to MS-DOS format.

       -      (1.71) A change was made that now permits use of the shared
              library on the **IX PC.

       -      (1.71) VAX/VMS is now supported reasonably well.

       -      (2.00) A comment may now be attached to the archive itself.

       -      (2.00) The OO option allows forced overwriting of read-only
              files.

       -      (2.00) Zoo will no longer extract a file if a newer copy already
              exists on disk;  the S option will override this.

       -      (2.00) File attributes are preserved for **IX systems.

       -      (2.00) Multiple generations of the same file are supported.

       -      (2.00) Zoo will now act as a compression or decompression filter
              on a stream of data and will use a CRC value to check the
              integrity of a data stream that is uncompressed.

       -      (2.00) A bug was fixed that caused removal of a directory link
              if files were moved to an archive by the superuser on a **IX
              system.

       -      (2.00) The data recovery modifier @ was greatly enhanced.  Self-
              extracting archives created for MS-DOS systems can now be
              extracted by zoo on any system with help from fiz(1).

       -      (2.01) A bug was fixed that had caused the first generation of a
              file to sometimes unexpectedly show up in archive listings.

       -      (2.01) A bug was fixed that had caused the MS-DOS version to
              silently skip files that could not be extracted because of
              insufficient disk space.

       -      (2.01) A bug was fixed that had sometimes made it impossible to
              selectively extract a file by specifying its name, even though
              all files could be extracted from the archive by not specifying
              any filenames.  This occurred when a file had been archived on a
              longer-filename system (e.g. AmigaDOS) and extraction was
              attempted on a shorter-filename system (e.g. MS-DOS).

       -      (2.01) A change was made that will make zoo preserve the mode
              (file protection) of a zoo archive when it is packed.  This is
              effective only if zoo is compiled to preserve and restore file
              attributes.  Currently this is so only for **IX systems.

       -      (2.01) A bug was fixed that had caused an update of an archive
              to not always add all newer files.

       -      (2.01) Blanks around equal signs in commands given to "make"
              were removed from the mk* scripts for better compatibility with
              more **IX implementations including Sun's.

       -      (2.1) Compression is now greatly improved if the "h" option is
              used.

       -      (2.1) The default behavior is to preserve full pathnames during
              extraction.

       -      (2.1) On some systems, extraction of files using the older
              (default) compression method is greatly speeded up.

       -      (2.1) Extended multiscreen help is available.

       -      (2.1) Memory allocation is improved, so that the MS-DOS version
              will not prematurely abort when updating a large archive.

       -      (2.1) The VAX/VMS version preserves file timestamps during
              extraction.

       -      (2.1) The default archive-wide generation limit, when
              generations are enabled, is 3.

FUTURE DIRECTIONS

       A revised version of zoo is in the works that will be able to write
       newly-created archives to standard output and will support multivolume
       archives.  It will be upward and downward compatible with this version
       of zoo.

ACKNOWLEDGEMENTS

       The zoo archiver was initially developed using Microsoft C 3.0 on a PC
       clone manufactured by Toshiba of Japan and almost sold by Xerox.
       Availability of the following systems was helpful in achieving
       portability: Paul Homchick's Compaq running Microport System V/AT;  The
       Eskimo BBS somewhere in Oregon running Xenix/68000; Greg Laskin's
       system 'gryphon' which is an Intel 310 running Xenix/286;  Ball State
       University's AT&T 3B2/300, UNIX PC, and VAX-11/785 (4.3BSD and VAX/VMS)
       systems.  In addition J. Brian Waters provided feedback to help me make
       the code compilable on his Amiga using Manx/Aztec C.  The executable
       version 2.0 for MS-DOS is currently compiled with Borland's Turbo C++
       1.0.

       Thanks are due to the following people and many others too numerous to
       mention.

       J. Brian Waters <jbwaters@bsu-cs.bsu.edu>, who has worked diligently to
       port zoo to AmigaDOS, created Amiga-specific code, and continues
       keeping it updated.

       Paul Homchick <rutgers!cgh!paul>, who provided numerous detailed
       reports about some nasty bugs.

       Bill Davidsen <davidsen@crdos1.crd.ge.com>, who provided numerous
       improvements to this manual, contributed multiscreen help, and provided
       many useful bug reports, bug fixes, code improvements, and suggestions.

       Mark Alexander <amdahl!drivax!alexande>, who provided me with some bug
       fixes.

       Haruhiko Okumura, who wrote the ar archiver and some excellent
       compression code, which I adapted for use in zoo.

       Randal L. Barnes <rlb@skyler.mavd.honeywell.com>, who (with Randy
       Magnuson) wrote the code to support the preservation of file timestamps
       under VAX/VMS.

       Raymond D. Gardner, who contributed replacement uncompression code that
       on some systems is twice as fast as the original.

       Greg Yachuk and Andre Van Dalen, who independently modified MS-DOS zoo
       to support multivolume archives.  (This support is not yet in this
       official release.)

AUTHOR

       Rahul Dhesi