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Working with zip and unzip represents some challenges for Unix admins who get used to gzip and other Unix style utilities, as those two originated in DOS which ahs different conventions then Unix and those conventions are still preserved in parameters.
To zip the current directory (zip file should be put into other directory recursively (the whole tree) use
zip -r f:\public_html.zip *
To zip the whole directory you can also specify it explicitly:
zip -r f:\public_html.zip c:\public_html
For example, if you want to unzip many ZIP archives in a directory, the command:
doesn't work. To fix this situation you need to put the pattern in single quotes:
Or you can create an alias unzipall that will use Unix conventions. For example
alias unzipall='ls *.zip | xargs -l unzip'
You could also use a loop to unzip each file:
for x in /path/to/archives/*.zip; do unzip "$x"; done
for x in $(ls /path/to/archives/*.zip 2>/dev/null); do unzip $x; done
Unlike many Unix commands (e.g., gzip and bzip2), the last argument to unzip isn't an arbitrarily long list of files. To process the command
the shell expands the wildcard, so (assuming you have files named zipfile1.zip to zipfile4.zip) to
unzip zipfile1.zip zipfile2.zip zipfile3.zip zipfile4.zip
The first argument plays special role in unzip -- it specifies the archive to work with. Subsequent arguments are treated as files to extract. So this command attempts to extract zipfile2.zip, zipfile3.zip, and zipfile4.zip from the archive zipfile1.zip. Naturally this command fails unless zipfile1.zip actually contains files with those names.
The first method prevents the shell from expanding the wildcard by using single quotes. However, that only works if there is only one wildcard. The second and third methods work around that by running an explicit unzip command for each ZIP file found when the shell expands the wildcards, or returns the result of the ls command.
The ls version is used because the default behavior of bash (and sh) is to return unmatched patterns unchanged. That means you would be trying to unzip a file called /path/to/date*/name/*.zip if no files match the wildcard pattern. But command ls will simply return null on STDOUT, and an error that we throw away on STDERR.
You can set the shopt -s nullglob option to cause filename patterns that match no files to expand to a null string, rather than themselves.
[Systems using EBCDIC] Translate file to ASCII format.
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.
[VM/CMS and MVS] force file to be read binary (default is text).
[TANDEM] set Edit/Enscribe formatting options with n defined as
zip -b /tmp stuff *
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.
Remove (delete) entries from a zip archive. For example:
zip -d foo foo/tom/junk foo/harry/\* \*.o
Under systems where the shell does not expand wildcards, such as MSDOS, the backslashes are not needed. The above would then be
zip -d foo foo/tom/junk foo/harry/* *.o
[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.
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
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.
[OS/2] Use the .LONGNAME Extended Attribute (if found) as filename.
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
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).
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.
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 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.
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.
Display the zip help information (this also appears if zip is run with no arguments).
zip -r foo . -i \*.c
pkzip -rP foo *.c
zip -r foo . -firstname.lastname@example.org
[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.
Store just the name of a saved file (junk the path), and do not store directory names. By default, zip will store the full path (relative to the current path).
[MacOS] record Fullpath (+ Volname). The complete path including volume will be stored. By default the relative path will be stored.
Strip any prepended data (e.g. a SFX stub) from the archive.
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.
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 ensures that unzip -a on Unix will get back an exact copy of the original file, to undo the effect of zip -l. See the note on binary detection for -ll below.
Translate the MSDOS end-of-line CR LF into Unix LF. This option should not be used on binary files and a warning will be issued when a file is converted that later is detected to be binary. This option can be used on MSDOS if the zip file is intended for unzip under Unix.
Display the zip license.
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.
zip -rn .Z:.zip:.tiff:.gif:.snd foo foo
setenv ZIPOPT "-n .gif:.zip"
zip -n : foo
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).
[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.
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
Quiet mode; eliminate informational messages and comment prompts. (Useful, for example, in shell scripts and background tasks).
[QDOS] store information about the file in the file header with n defined as
Travel the directory structure recursively; for example:
zip -r foo foo
Travel the directory structure recursively starting at the current directory; for example:
zip -R foo '*.c'
pkzip -rP foo *.c
[MSDOS, OS/2, WIN32 and ATARI] Include system and hidden files.
zip -rt 12071991 infamy foo
zip -rt 1991-12-07 infamy foo
zip -rtt 11301995 infamy foo
zip -rtt 1995-11-30 infamy foo
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.
Replace (update) an existing entry in the zip archive only if it has been modified more recently than the version already in the zip archive. For example:
zip -u stuff *
Note that the -u option with no arguments acts like the -f (freshen) option.
Verbose mode or print diagnostic version info.
When -v is the only command line argument, and either stdin or 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.
[VMS] Save VMS file attributes and use portable form. zip archives created with this option are truncated at EOF but still may not be usable on other systems depending on the file types being zipped.
[VMS] Save VMS file attributes. zip archives created with this option include the entire file and should be able to recreate most VMS files on VMS systems but these archives will generally not be usable on other systems.
[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).
zip -r foo foo -x \*.o
zip -r foo foo -email@example.com
Do not save extra file attributes (Extended Attributes on OS/2, uid/gid and file times on Unix).
Store symbolic links as such in the zip archive, instead of compressing and storing the file referred to by the link (UNIX only).
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 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
The simplest example:
Because of the way the shell does filename substitution, files starting with "." are not included; to include these as well:
To zip up an entire directory, the command:
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:
When given the name of an existing zip archive, zip will replace identically named entries in the zip archive or add 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:
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:
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:
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.
This section applies only to UNIX, though the ?, *, and  special characters are implemented on other systems including MSDOS and Win32. 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:
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).
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zipcloak [-dhL] [-b path] zipfile
zipnote [-hwL] [-b path] zipfile
zipsplit [-hiLpst] [-n size] [-b path] zipfile
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 2.31 is compatible with PKZIP 2.04. Note that PKUNZIP 1.10 cannot extract files produced by PKZIP 2.04 or zip 2.31. 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.
contains default options that will be used when running zip
[Not on RISC OS and VMS] see ZIPOPT
compress(1), shar(1L), tar(1), unzip(1L), gzip(1L)
The exit status (or error level) approximates the exit codes defined by PKWARE and takes on the following values, except under VMS:
normal; no errors or warnings detected.
unexpected end of zip file.
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.
zip was unable to allocate memory for one or more buffers during program initialization.
a severe error in the zipfile format was detected. Processing probably failed immediately.
entry too large to split (with zipsplit), read, or write
invalid comment format
zip -T failed or out of memory
the user aborted zip prematurely with control-C (or similar)
zip encountered an error while using a temp file
read or seek error
zip has nothing to do
missing or empty zip file
error writing to a file
zip was unable to create a file to write to
bad command line parameters
zip could not open a specified file to read
zip 2.31 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 2.31 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.
Development of Zip 3.0 is underway. See that source distribution for many new features and the latest bug fixes.
Copyright (C) 1997-2005 Info-ZIP.
Copyright (C) 1990-1997 Mark Adler, Richard B. Wales, Jean-loup Gailly, Onno van der Linden, Kai Uwe Rommel, Igor 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 to: zip-bugs at www.info-zip.org. 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.
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.
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