ZIP(1L) Info-ZIP (14 August 1999 (v2.3)) ZIP(1L)
NAME
zip, zipcloak, zipnote, zipsplit - package and compress
(archive) files
SYNOPSIS
zip [-aABcdDeEfFghjklLmoqrRSTuvVwXyz!@$] [-b path]
[-n suffixes] [-t mmddyyyy] [-tt mmddyyyy] [ zipfile [ file1
file2 ...]] [-xi list]
zipcloak [-dhL] [-b path] zipfile
zipnote [-hwL] [-b path] zipfile
zipsplit [-hiLpst] [-n size] [-b path] zipfile
DESCRIPTION
zip is a compression and file packaging utility for Unix,
VMS, MSDOS, OS/2, Windows NT, Minix, Atari and Macintosh,
Amiga and Acorn RISC OS.
It is analogous to a combination of the UNIX commands tar(1)
and compress(1) and is compatible with PKZIP (Phil Katz's
ZIP for MSDOS systems).
A companion program (unzip(1L)), unpacks zip archives. The
zip and unzip(1L) programs can work with archives produced
by PKZIP, and PKZIP and PKUNZIP can work with archives
produced by zip. zip version 2.3 is compatible with PKZIP
2.04. Note that PKUNZIP 1.10 cannot extract files produced
by PKZIP 2.04 or zip 2.3. You must use PKUNZIP 2.04g or
unzip 5.0p1 (or later versions) to extract them.
For a brief help on zip and unzip, run each without
specifying any parameters on the command line.
The program is useful for packaging a set of files for
distribution; for archiving files; and for saving disk space
by temporarily compressing unused files or directories.
The zip program puts one or more compressed files into a
single zip archive, along with information about the files
(name, path, date, time of last modification, protection,
and check information to verify file integrity). An entire
directory structure can be packed into a zip archive with a
single command. Compression ratios of 2:1 to 3:1 are common
for text files. zip has one compression method (deflation)
and can also store files without compression. zip
automatically chooses the better of the two for each file to
be compressed.
When given the name of an existing zip archive, zip will
replace identically named entries in the zip archive or add
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entries for new names. For example, if foo.zip exists and
contains foo/file1 and foo/file2, and the directory foo
contains the files foo/file1 and foo/file3, then:
zip -r foo foo
will replace foo/file1 in foo.zip and add foo/file3 to
foo.zip. After this, foo.zip contains foo/file1, foo/file2,
and foo/file3, with foo/file2 unchanged from before.
If the file list is specified as -@, [Not on MacOS] zip
takes the list of input files from standard input. Under
UNIX, this option can be used to powerful effect in
conjunction with the find(1) command. For example, to
archive all the C source files in the current directory and
its subdirectories:
find . -name "*.[ch]" -print | zip source -@
(note that the pattern must be quoted to keep the shell from
expanding it). zip will also accept a single dash ("-") as
the zip file name, in which case it will write the zip file
to standard output, allowing the output to be piped to
another program. For example:
zip -r - . | dd of=/dev/nrst0 obs=16k
would write the zip output directly to a tape with the
specified block size for the purpose of backing up the
current directory.
zip also accepts a single dash ("-") as the name of a file
to be compressed, in which case it will read the file from
standard input, allowing zip to take input from another
program. For example:
tar cf - . | zip backup -
would compress the output of the tar command for the purpose
of backing up the current directory. This generally produces
better compression than the previous example using the -r
option, because zip can take advantage of redundancy between
files. The backup can be restored using the command
unzip -p backup | tar xf -
When no zip file name is given and stdout is not a terminal,
zip acts as a filter, compressing standard input to standard
output. For example,
tar cf - . | zip | dd of=/dev/nrst0 obs=16k
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is equivalent to
tar cf - . | zip - - | dd of=/dev/nrst0 obs=16k
zip archives created in this manner can be extracted with
the program funzip which is provided in the unzip package,
or by gunzip which is provided in the gzip package. For
example:
dd if=/dev/nrst0 ibs=16k | funzip | tar xvf -
When changing an existing zip archive, zip will write a
temporary file with the new contents, and only replace the
old one when the process of creating the new version has
been completed without error.
If the name of the zip archive does not contain an
extension, the extension .zip is added. If the name already
contains an extension other than .zip the existing extension
is kept unchanged.
OPTIONS
-a [Systems using EBCDIC] Translate file to ASCII format.
-A Adjust self-extracting executable archive. A self-
extracting executable archive is created by prepending
the SFX stub to an existing archive. The -A option
tells zip to adjust the entry offsets stored in the
archive to take into account this "preamble" data.
Note: self-extracting archives for the Amiga are a special
case. At present, only the Amiga port of Zip is capable of
adjusting or updating these without corrupting them. -J can
be used to remove the SFX stub if other updates need to be
made.
-B [VM/CMS and MVS] force file to be read binary (default
is text).
-Bn [TANDEM] set Edit/Enscribe formatting options with n
defined as
bit 0: Don't add delimiter (Edit/Enscribe)
bit 1: Use LF rather than CR/LF as delimiter
(Edit/Enscribe)
bit 2: Space fill record to maximum record length
(Enscribe)
bit 3: Trim trailing space (Enscribe)
bit 8: Force 30K (Expand) large read for unstructured
files
-b path
Use the specified path for the temporary zip archive.
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For example:
zip -b /tmp stuff *
will put the temporary zip archive in the directory
/tmp, copying over stuff.zip to the current directory
when done. This option is only useful when updating an
existing archive, and the file system containing this
old archive does not have enough space to hold both old
and new archives at the same time.
-c Add one-line comments for each file. File operations
(adding, updating) are done first, and the user is then
prompted for a one-line comment for each file. Enter
the comment followed by return, or just return for no
comment.
-d Remove (delete) entries from a zip archive. For
example:
zip -d foo foo/tom/junk foo/harry/\* \*.o
will remove the entry foo/tom/junk, all of the files
that start with foo/harry/, and all of the files that
end with .o (in any path). Note that shell pathname
expansion has been inhibited with backslashes, so that
zip can see the asterisks, enabling zip to match on the
contents of the zip archive instead of the contents of
the current directory.
Under MSDOS, -d is case sensitive when it matches names
in the zip archive. This requires that file names be
entered in upper case if they were zipped by PKZIP on
an MSDOS system.
-df [MacOS] Include only data-fork of files zipped into the
archive. Good for exporting files to foreign
operating-systems. Resource-forks will be ignored at
all.
-D Do not create entries in the zip archive for
directories. Directory entries are created by default
so that their attributes can be saved in the zip
archive. The environment variable ZIPOPT can be used
to change the default options. For example under Unix
with sh:
ZIPOPT="-D"; export ZIPOPT
(The variable ZIPOPT can be used for any option except
-i and -x and can include several options.) The option
-D is a shorthand for -x "*/" but the latter cannot be
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set as default in the ZIPOPT environment variable.
-e Encrypt the contents of the zip archive using a
password which is entered on the terminal in response
to a prompt (this will not be echoed; if standard error
is not a tty, zip will exit with an error). The
password prompt is repeated to save the user from
typing errors.
-E [OS/2] Use the .LONGNAME Extended Attribute (if found)
as filename.
-f Replace (freshen) an existing entry in the zip archive
only if it has been modified more recently than the
version already in the zip archive; unlike the update
option (-u) this will not add files that are not
already in the zip archive. For example:
zip -f foo
This command should be run from the same directory from
which the original zip command was run, since paths
stored in zip archives are always relative.
Note that the timezone environment variable TZ should
be set according to the local timezone in order for the
-f , -u and -o options to work correctly.
The reasons behind this are somewhat subtle but have to
do with the differences between the Unix-format file
times (always in GMT) and most of the other operating
systems (always local time) and the necessity to
compare the two. A typical TZ value is ``MET-1MEST''
(Middle European time with automatic adjustment for
``summertime'' or Daylight Savings Time).
-F Fix the zip archive. This option can be used if some
portions of the archive are missing. It is not
guaranteed to work, so you MUST make a backup of the
original archive first.
When doubled as in -FF the compressed sizes given
inside the damaged archive are not trusted and zip
scans for special signatures to identify the limits
between the archive members. The single -F is more
reliable if the archive is not too much damaged, for
example if it has only been truncated, so try this
option first.
Neither option will recover archives that have been
incorrectly transferred in ascii mode instead of
binary. After the repair, the -t option of unzip may
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show that some files have a bad CRC. Such files cannot
be recovered; you can remove them from the archive
using the -d option of zip.
-g Grow (append to) the specified zip archive, instead of
creating a new one. If this operation fails, zip
attempts to restore the archive to its original state.
If the restoration fails, the archive might become
corrupted. This option is ignored when there's no
existing archive or when at least one archive member
must be updated or deleted.
-h Display the zip help information (this also appears if
zip is run with no arguments).
-i files
Include only the specified files, as in:
zip -r foo . -i \*.c
which will include only the files that end in .c in the
current directory and its subdirectories. (Note for
PKZIP users: the equivalent command is
pkzip -rP foo *.c
PKZIP does not allow recursion in directories other
than the current one.) The backslash avoids the shell
filename substitution, so that the name matching is
performed by zip at all directory levels.
Also possible:
zip -r foo . -i@include.lst
which will only include the files in the current
directory and its subdirectories that match the
patterns in the file include.lst.
-I [Acorn RISC OS] Don't scan through Image files. When
used, zip will not consider Image files (eg. DOS
partitions or Spark archives when SparkFS is loaded) as
directories but will store them as single files.
For example, if you have SparkFS loaded, zipping a
Spark archive will result in a zipfile containing a
directory (and its content) while using the 'I' option
will result in a zipfile containing a Spark archive.
Obviously this second case will also be obtained
(without the 'I' option) if SparkFS isn't loaded.
-j Store just the name of a saved file (junk the path),
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and do not store directory names. By default, zip will
store the full path (relative to the current path).
-jj [MacOS] record Fullpath (+ Volname). The complete path
including volume will be stored. By default the
relative path will be stored.
-J Strip any prepended data (e.g. a SFX stub) from the
archive.
-k Attempt to convert the names and paths to conform to
MSDOS, store only the MSDOS attribute (just the user
write attribute from UNIX), and mark the entry as made
under MSDOS (even though it was not); for compatibility
with PKUNZIP under MSDOS which cannot handle certain
names such as those with two dots.
-l Translate the Unix end-of-line character LF into the
MSDOS convention CR LF. This option should not be used
on binary files. This option can be used on Unix if
the zip file is intended for PKUNZIP under MSDOS. If
the input files already contain CR LF, this option adds
an extra CR. This ensure that unzip -a on Unix will get
back an exact copy of the original file, to undo the
effect of zip -l.
-ll Translate the MSDOS end-of-line CR LF into Unix LF.
This option should not be used on binary files. This
option can be used on MSDOS if the zip file is intended
for unzip under Unix.
-L Display the zip license.
-m Move the specified files into the zip archive;
actually, this deletes the target directories/files
after making the specified zip archive. If a directory
becomes empty after removal of the files, the directory
is also removed. No deletions are done until zip has
created the archive without error. This is useful for
conserving disk space, but is potentially dangerous so
it is recommended to use it in combination with -T to
test the archive before removing all input files.
-n suffixes
Do not attempt to compress files named with the given
suffixes. Such files are simply stored (0% compression)
in the output zip file, so that zip doesn't waste its
time trying to compress them. The suffixes are
separated by either colons or semicolons. For example:
zip -rn .Z:.zip:.tiff:.gif:.snd foo foo
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will copy everything from foo into foo.zip, but will
store any files that end in .Z, .zip, .tiff, .gif, or
.snd without trying to compress them (image and sound
files often have their own specialized compression
methods). By default, zip does not compress files with
extensions in the list .Z:.zip:.zoo:.arc:.lzh:.arj.
Such files are stored directly in the output archive.
The environment variable ZIPOPT can be used to change
the default options. For example under Unix with csh:
setenv ZIPOPT "-n .gif:.zip"
To attempt compression on all files, use:
zip -n : foo
The maximum compression option -9 also attempts
compression on all files regardless of extension.
On Acorn RISC OS systems the suffixes are actually
filetypes (3 hex digit format). By default, zip does
not compress files with filetypes in the list
DDC:D96:68E (i.e. Archives, CFS files and PackDir
files).
-N [Amiga, MacOS] Save Amiga or MacOS filenotes as zipfile
comments. They can be restored by using the -N option
of unzip. If -c is used also, you are prompted for
comments only for those files that do not have
filenotes.
-o Set the "last modified" time of the zip archive to the
latest (oldest) "last modified" time found among the
entries in the zip archive. This can be used without
any other operations, if desired. For example:
zip -o foo
will change the last modified time of foo.zip to the
latest time of the entries in foo.zip.
In this case, all the files and directories in foo are
saved in a zip archive named foo.zip, including files
with names starting with ".", since the recursion does
not use the shell's file-name substitution mechanism.
If you wish to include only a specific subset of the
files in directory foo and its subdirectories, use the
-i option to specify the pattern of files to be
included. You should not use -r with the name ".*",
since that matches ".." which will attempt to zip up
the parent directory (probably not what was intended).
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ZIP(1L) Info-ZIP (14 August 1999 (v2.3)) ZIP(1L)-R Travel the directory structure recursively starting at
the current directory; for example:
zip -R foo '*.c'
In this case, all the files matching *.c in the tree
starting at the current directory are stored into a zip
archive named foo.zip. Note for PKZIP users: the
equivalent command is
pkzip -rP foo *.c
-S [MSDOS, OS/2, WIN32 and ATARI] Include system and
hidden files.
[MacOS] Includes finder invisible files, which are
ignored otherwise.
-t mmddyyyy
Do not operate on files modified prior to the specified
date, where mm is the month (0-12), dd is the day of
the month (1-31), and yyyy is the year. The ISO 8601
date format yyyy-mm-dd is also accepted. For example:
zip -rt 12071991 infamy foo
zip -rt 1991-12-07 infamy foo
will add all the files in foo and its subdirectories
that were last modified on or after 7 December 1991, to
the zip archive infamy.zip.
-tt mmddyyyy
Do not operate on files modified after or at the
specified date, where mm is the month (0-12), dd is the
day of the month (1-31), and yyyy is the year. The ISO
8601 date format yyyy-mm-dd is also accepted. For
example:
zip -rtt 11301995 infamy foo
zip -rtt 1995-11-30 infamy foo
will add all the files in foo and its subdirectories
that were last modified before the 30 November 1995, to
the zip archive infamy.zip.
-T Test the integrity of the new zip file. If the check
fails, the old zip file is unchanged and (with the -m
option) no input files are removed.
-u Replace (update) an existing entry in the zip archive
only if it has been modified more recently than the
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version already in the zip archive. For example:
zip -u stuff *
will add any new files in the current directory, and
update any files which have been modified since the zip
archive stuff.zip was last created/modified (note that
zip will not try to pack stuff.zip into itself when you
do this).
Note that the -u option with no arguments acts like the
-f (freshen) option.
-v Verbose mode or print diagnostic version info.
Normally, when applied to real operations, this option
enables the display of a progress indicator during
compression and requests verbose diagnostic info about
zipfile structure oddities.
When -v is the only command line argument, and stdout
is not redirected to a file, a diagnostic screen is
printed. In addition to the help screen header with
program name, version, and release date, some pointers
to the Info-ZIP home and distribution sites are given.
Then, it shows information about the target environment
(compiler type and version, OS version, compilation
date and the enabled optional features used to create
the zip executable.
-V [VMS] Save VMS file attributes. zip archives created
with this option will generally not be usable on other
systems.
-w [VMS] Append the version number of the files to the
name, including multiple versions of files. (default:
use only the most recent version of a specified file).
-x files
Explicitly exclude the specified files, as in:
zip -r foo foo -x \*.o
which will include the contents of foo in foo.zip while
excluding all the files that end in .o. The backslash
avoids the shell filename substitution, so that the
name matching is performed by zip at all directory
levels.
Also possible:
zip -r foo foo -x@exclude.lst
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which will include the contents of foo in foo.zip while
excluding all the files that match the patterns in the
file exclude.lst.
-X Do not save extra file attributes (Extended Attributes
on OS/2, uid/gid and file times on Unix).
-y Store symbolic links as such in the zip archive,
instead of compressing and storing the file referred to
by the link (UNIX only).
-z Prompt for a multi-line comment for the entire zip
archive. The comment is ended by a line containing
just a period, or an end of file condition (^D on UNIX,
^Z on MSDOS, OS/2, and VAX/VMS). The comment can be
taken from a file:
zip -z foo < foowhat
-# Regulate the speed of compression using the specified
digit #, where -0 indicates no compression (store all
files), -1 indicates the fastest compression method
(less compression) and -9 indicates the slowest
compression method (optimal compression, ignores the
suffix list). The default compression level is -6.
-! [WIN32] Use priviliges (if granted) to obtain all
aspects of WinNT security.
-@ Take the list of input files from standard input. Only
one filename per line.
-$ [MSDOS, OS/2, WIN32] Include the volume label for the
the drive holding the first file to be compressed. If
you want to include only the volume label or to force a
specific drive, use the drive name as first file name,
as in:
zip -$ foo a: c:bar
EXAMPLES
The simplest example:
zip stuff *
creates the archive stuff.zip (assuming it does not exist)
and puts all the files in the current directory in it, in
compressed form (the .zip suffix is added automatically,
unless that archive name given contains a dot already; this
allows the explicit specification of other suffixes).
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Because of the way the shell does filename substitution,
files starting with "." are not included; to include these
as well:
zip stuff .* *
Even this will not include any subdirectories from the
current directory.
To zip up an entire directory, the command:
zip -r foo foo
creates the archive foo.zip, containing all the files and
directories in the directory foo that is contained within
the current directory.
You may want to make a zip archive that contains the files
in foo, without recording the directory name, foo. You can
use the -j option to leave off the paths, as in:
zip -j foo foo/*
If you are short on disk space, you might not have enough
room to hold both the original directory and the
corresponding compressed zip archive. In this case, you can
create the archive in steps using the -m option. If foo
contains the subdirectories tom, dick, and harry, you can:
zip -rm foo foo/tom
zip -rm foo foo/dick
zip -rm foo foo/harry
where the first command creates foo.zip, and the next two
add to it. At the completion of each zip command, the last
created archive is deleted, making room for the next zip
command to function.
PATTERN MATCHING
This section applies only to UNIX. Watch this space for
details on MSDOS and VMS operation.
The UNIX shells (sh(1) and csh(1)) do filename substitution
on command arguments. The special characters are:
? match any single character
* match any number of characters (including none)
[] match any character in the range indicated within the
brackets (example: [a-f], [0-9]).
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When these characters are encountered (without being escaped
with a backslash or quotes), the shell will look for files
relative to the current path that match the pattern, and
replace the argument with a list of the names that matched.
The zip program can do the same matching on names that are
in the zip archive being modified or, in the case of the -x
(exclude) or -i (include) options, on the list of files to
be operated on, by using backslashes or quotes to tell the
shell not to do the name expansion. In general, when zip
encounters a name in the list of files to do, it first looks
for the name in the file system. If it finds it, it then
adds it to the list of files to do. If it does not find it,
it looks for the name in the zip archive being modified (if
it exists), using the pattern matching characters described
above, if present. For each match, it will add that name to
the list of files to be processed, unless this name matches
one given with the -x option, or does not match any name
given with the -i option.
The pattern matching includes the path, and so patterns like
\*.o match names that end in ".o", no matter what the path
prefix is. Note that the backslash must precede every
special character (i.e. ?*[]), or the entire argument must
be enclosed in double quotes ("").
In general, use backslash to make zip do the pattern
matching with the -f (freshen) and -d (delete) options, and
sometimes after the -x (exclude) option when used with an
appropriate operation (add, -u, -f, or -d).
ENVIRONMENT
ZIPOPT
contains default options that will be used when running
zip
ZIP [Not on RISC OS and VMS] see ZIPOPT
Zip$Options
[RISC OS] see ZIPOPT
Zip$Exts
[RISC OS] contains extensions separated by a : that
will cause native filenames with one of the specified
extensions to be added to the zip file with basename
and extension swapped. zip
ZIP_OPTS
[VMS] see ZIPOPT
SEE ALSO
compress(1), shar(1L), tar(1), unzip(1L), gzip(1L)
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DIAGNOSTICS
The exit status (or error level) approximates the exit codes
defined by PKWARE and takes on the following values, except
under VMS:
0 normal; no errors or warnings detected.
2 unexpected end of zip file.
3 a generic error in the zipfile format was
detected. Processing may have completed
successfully anyway; some broken zipfiles created
by other archivers have simple work-arounds.
4 zip was unable to allocate memory for one or more
buffers during program initialization.
5 a severe error in the zipfile format was detected.
Processing probably failed immediately.
6 entry too large to be split with zipsplit
7 invalid comment format
8 zip -T failed or out of memory
9 the user aborted zip prematurely with control-C
(or similar)
10 zip encountered an error while using a temp file
11 read or seek error
12 zip has nothing to do
13 missing or empty zip file
14 error writing to a file
15 zip was unable to create a file to write to
16 bad command line parameters
18 zip could not open a specified file to read
VMS interprets standard Unix (or PC) return values as other,
scarier-looking things, so zip instead maps them into VMS-
style status codes. The current mapping is as follows: 1
(success) for normal exit,
and (0x7fff000? + 16*normal_zip_exit_status) for all
errors, where the `?' is 0 (warning) for zip value 12, 2
(error) for the zip values 3, 6, 7, 9, 13, 16, 18, and 4
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(fatal error) for the remaining ones.
BUGS
zip 2.3 is not compatible with PKUNZIP 1.10. Use zip 1.1 to
produce zip files which can be extracted by PKUNZIP 1.10.
zip files produced by zip 2.3 must not be updated by zip 1.1
or PKZIP 1.10, if they contain encrypted members or if they
have been produced in a pipe or on a non-seekable device.
The old versions of zip or PKZIP would create an archive
with an incorrect format. The old versions can list the
contents of the zip file but cannot extract it anyway
(because of the new compression algorithm). If you do not
use encryption and use regular disk files, you do not have
to care about this problem.
Under VMS, not all of the odd file formats are treated
properly. Only stream-LF format zip files are expected to
work with zip. Others can be converted using Rahul Dhesi's
BILF program. This version of zip handles some of the
conversion internally. When using Kermit to transfer zip
files from Vax to MSDOS, type "set file type block" on the
Vax. When transfering from MSDOS to Vax, type "set file
type fixed" on the Vax. In both cases, type "set file type
binary" on MSDOS.
Under VMS, zip hangs for file specification that uses DECnet
syntax foo::*.*.
On OS/2, zip cannot match some names, such as those
including an exclamation mark or a hash sign. This is a bug
in OS/2 itself: the 32-bit DosFindFirst/Next don't find such
names. Other programs such as GNU tar are also affected by
this bug.
Under OS/2, the amount of Extended Attributes displayed by
DIR is (for compatibility) the amount returned by the 16-bit
version of DosQueryPathInfo(). Otherwise OS/2 1.3 and 2.0
would report different EA sizes when DIRing a file.
However, the structure layout returned by the 32-bit
DosQueryPathInfo() is a bit different, it uses extra padding
bytes and link pointers (it's a linked list) to have all
fields on 4-byte boundaries for portability to future RISC
OS/2 versions. Therefore the value reported by zip (which
uses this 32-bit-mode size) differs from that reported by
DIR. zip stores the 32-bit format for portability, even the
16-bit MS-C-compiled version running on OS/2 1.3, so even
this one shows the 32-bit-mode size.
AUTHORS
Copyright (C) 1990-1997 Mark Adler, Richard B. Wales, Jean-
loup Gailly, Onno van der Linden, Kai Uwe Rommel, Igor
Page 15 (printed 12/21/99)
ZIP(1L) Info-ZIP (14 August 1999 (v2.3)) ZIP(1L)
Mandrichenko, John Bush and Paul Kienitz. Permission is
granted to any individual or institution to use, copy, or
redistribute this software so long as all of the original
files are included, that it is not sold for profit, and that
this copyright notice is retained.
LIKE ANYTHING ELSE THAT'S FREE, ZIP AND ITS ASSOCIATED
UTILITIES ARE PROVIDED AS IS AND COME WITH NO WARRANTY OF
ANY KIND, EITHER EXPRESSED OR IMPLIED. IN NO EVENT WILL THE
COPYRIGHT HOLDERS BE LIABLE FOR ANY DAMAGES RESULTING FROM
THE USE OF THIS SOFTWARE.
Please send bug reports and comments by email to:
zip-bugs@lists.wku.edu. For bug reports, please include the
version of zip (see zip-h ), the make options used to
compile it see zip-v ), the machine and operating system in
use, and as much additional information as possible.
ACKNOWLEDGEMENTS
Thanks to R. P. Byrne for his Shrink.Pas program, which
inspired this project, and from which the shrink algorithm
was stolen; to Phil Katz for placing in the public domain
the zip file format, compression format, and .ZIP filename
extension, and for accepting minor changes to the file
format; to Steve Burg for clarifications on the deflate
format; to Haruhiko Okumura and Leonid Broukhis for
providing some useful ideas for the compression algorithm;
to Keith Petersen, Rich Wales, Hunter Goatley and Mark Adler
for providing a mailing list and ftp site for the Info-ZIP
group to use; and most importantly, to the Info-ZIP group
itself (listed in the file infozip.who) without whose
tireless testing and bug-fixing efforts a portable zip would
not have been possible. Finally we should thank (blame) the
first Info-ZIP moderator, David Kirschbaum, for getting us
into this mess in the first place. The manual page was
rewritten for UNIX by R. P. C. Rodgers.
Page 16 (printed 12/21/99)
