unzip

List, test and extract compressed files in a ZIP archive.

Syntax
      unzip [-Z] [-cflptTuvz[abjnoqsCDKLMUVWX$/:^]] file[.zip] [file(s) ...] [-x xfile(s) ...] [-d exdir]

Basic Examples:

UnZip the file demo.txt on the desktop to archive.zip:

$ unzip archive.zip

Zip the contents of the folder ~/work including subfolders and system files:

$ cd ~
$ zip -r workfolder.zip work

Zip the contents of the folder ~/work including subfolders but excluding any system files that start with a period or double underscore:

$ cd ~
$ zip -r workfolder.zip work -x ".*" -x "__*"

This will ensure that no additional files are seen if the zip is extracted on a non-Apple PC.

Arguments
      file[.zip]
              Path of the ZIP archive(s).  If the file specification is a wildcard, each matching file is
              processed in an order determined by the Operating System (or file system).  Only the filename can
              be a wildcard; the path itself cannot.  Wildcard expressions are similar to those supported in
              commonly used Unix shells (sh, ksh, csh) and may contain:

              *      matches a sequence of 0 or more characters

              ?      matches exactly 1 character

              [...]  matches any single character found inside the brackets; ranges are specified by a
                     beginning character, a hyphen, and an ending character.  If an exclamation point or a
                     caret (`!' or `^') follows the left bracket, then the range of characters within the
                     brackets is complemented (that is, anything except the characters inside the brackets is
                     considered a match).  To specify a verbatim left bracket, the three-character sequence
                     '[[]' has to be used.

              (Be sure to quote any character that might otherwise be interpreted or modified by the Operating
              System, particularly under Unix and VMS.)  If no matches are found, the specification is assumed
              to be a literal filename; and if that also fails, the suffix .zip is appended.  Note that self-
              extracting ZIP files are supported, as with any other ZIP archive; just specify the .exe suffix
              (if any) explicitly.

       [file(s)]
              An optional list of archive members to be processed, separated by spaces.  (VMS versions compiled
              with VMSCLI defined must delimit files with commas instead.  See -v in OPTIONS below.)  Regular
              expressions (wildcards) may be used to match multiple members; see above.  Again, be sure to
              quote expressions that would otherwise be expanded or modified by the Operating System.

       [-x xfile(s)]
              An optional list of archive members to be excluded from processing.  Since wildcard characters
              normally match (`/') directory separators (for exceptions see the option -W), this option may be
              used to exclude any files that are in subdirectories.  For example, 'unzip foo *.[ch] -x */*'
              would extract all C source files in the main directory, but none in any subdirectories.  Without
              the -x option, all C source files in all directories within the zipfile would be extracted.

       [-d exdir]
              An optional directory to which to extract files.  By default, all files and subdirectories are
              recreated in the current directory; the -d option allows extraction in an arbitrary directory
              (always assuming one has permission to write to the directory).  This option need not appear at
              the end of the command line; it is also accepted before the zipfile specification (with the
              normal options), immediately after the zipfile specification, or between the file(s) and the -x
              option.  The option and directory may be concatenated without any white space between them, but
              note that this may cause normal shell behavior to be suppressed.  In particular, '-d ~' (tilde)
              is expanded by Unix C shells into the name of the user’s home directory, but '-d~' is treated
              as a literal subdirectory '~' of the current directory.
Options    
       Note that, in order to support obsolescent hardware, unzip’s usage screen is limited to 22 or 23 lines
       and should therefore be considered only a reminder of the basic unzip syntax rather than an exhaustive
       list of all possible flags.  The exhaustive list follows:

       -Z     zipinfo(1L) mode.  If the first option on the command line is -Z, the remaining options are taken
              to be zipinfo(1L) options.  See the appropriate manual page for a description of these options.

       -A     [OS/2, Unix DLL] print extended help for the DLL’s programming interface (API).

       -c     extract files to stdout/screen ('CRT').  This option is similar to the -p option except that
              the name of each file is printed as it is extracted, the -a option is allowed, and ASCII-EBCDIC
              conversion is automatically performed if appropriate.  This option is not listed in the unzip
              usage screen.

       -f     freshen existing files, i.e., extract only those files that already exist on disk and that are
              newer than the disk copies.  By default unzip queries before overwriting, but the -o option may
              be used to suppress the queries.  Note that under many Operating Systems, the TZ (timezone)
              environment variable must be set correctly in order for -f and -u to work properly (under Unix
              the variable is usually set automatically).  The reasons for this are somewhat subtle but have to
              do with the differences between DOS-format file times (always local time) and Unix-format times
              (always in GMT/UTC) and the necessity to compare the two.  A typical TZ value is 'PST8PDT' (US
              Pacific time with automatic adjustment for Daylight Savings Time or 'summer time').

       -l     list archive files (short format).  The names, uncompressed file sizes and modification dates and
              times of the specified files are printed, along with totals for all files specified.  If UnZip
              was compiled with OS2_EAS defined, the -l option also lists columns for the sizes of stored OS/2
              extended attributes (EAs) and OS/2 access control lists (ACLs).  In addition, the zipfile comment
              and individual file comments (if any) are displayed.  If a file was archived from a single-case
              file system (for example, the old MS-DOS FAT file system) and the -L option was given, the
              filename is converted to lowercase and is prefixed with a caret (^).

       -p     extract files to pipe (stdout).  Nothing but the file data is sent to stdout, and the files are
              always extracted in binary format, just as they are stored (no conversions).

       -t     test archive files.  This option extracts each specified file in memory and compares the CRC
              (cyclic redundancy check, an enhanced checksum) of the expanded file with the original file’s
              stored CRC value.

       -T     [most OSes] set the timestamp on the archive(s) to that of the newest file in each one.  This
              corresponds to zip’s -go option except that it can be used on wildcard zipfiles (e.g., 'unzip -T
              \*.zip') and is much faster.

       -u     update existing files and create new ones if needed.  This option performs the same function as
              the -f option, extracting (with query) files that are newer than those with the same name on
              disk, and in addition it extracts those files that do not already exist on disk.  See -f above
              for information on setting the timezone properly.

       -v     list archive files (verbose format) or show diagnostic version info.  This option has evolved and
              now behaves as both an option and a modifier.  As an option it has two purposes:  when a zipfile
              is specified with no other options, -v lists archive files verbosely, adding to the basic -l info
              the compression method, compressed size, compression ratio and 32-bit CRC.  In contrast to most
              of the competing utilities, unzip removes the 12 additional header bytes of encrypted entries
              from the compressed size numbers.  Therefore, compressed size and compression ratio figures are
              independent of the entry’s encryption status and show the correct compression performance.  (The
              complete size of the encrypted compressed data stream for zipfile entries is reported by the more
              verbose zipinfo(1L) reports, see the separate manual.)  When no zipfile is specified (that is,
              the complete command is simply 'unzip -v'), a diagnostic screen is printed.  In addition to the
              normal header with release date and version, unzip lists the home Info-ZIP ftp site and where to
              find a list of other ftp and non-ftp sites; the target Operating System for which it was
              compiled, as well as (possibly) the hardware on which it was compiled, the compiler and version
              used, and the compilation date; any special compilation options that might affect the program’s
              operation (see also DECRYPTION below); and any options stored in environment variables that might
              do the same (see ENVIRONMENT OPTIONS below).  As a modifier it works in conjunction with other
              options (e.g., -t) to produce more verbose or debugging output; this is not yet fully implemented
              but will be in future releases.

       -z     display only the archive comment.

MODIFIERS
       -a     convert text files.  Ordinarily all files are extracted exactly as they are stored (as 'binary'
              files).  The -a option causes files identified by zip as text files (those with the `t' label in
              zipinfo listings, rather than `b') to be automatically extracted as such, converting line
              endings, end-of-file characters and the character set itself as necessary.  (For example, Unix
              files use line feeds (LFs) for end-of-line (EOL) and have no end-of-file (EOF) marker;
              Macintoshes use carriage returns (CRs) for EOLs; and most PC Operating Systems use CR+LF for EOLs
              and control-Z for EOF.  In addition, IBM mainframes and the Michigan Terminal System use EBCDIC
              rather than the more common ASCII character set, and NT supports Unicode.)  Note that zip’s
              identification of text files is by no means perfect; some 'text' files may actually be binary
              and vice versa.  unzip therefore prints '[text]' or '[binary]' as a visual check for each
              file it extracts when using the -a option.  The -aa option forces all files to be extracted as
              text, regardless of the supposed file type.  On VMS, see also -S.

       -b     [general] treat all files as binary (no text conversions).  This is a shortcut for ---a.

       -b     [Tandem] force the creation files with filecode type 180 ('C') when extracting Zip entries marked
              as "text". (On Tandem, -a is enabled by default, see above).

       -b     [VMS] auto-convert binary files (see -a above) to fixed-length, 512-byte record format.  Doubling
              the option (-bb) forces all files to be extracted in this format. When extracting to standard
              output (-c or -p option in effect), the default conversion of text record delimiters is disabled
              for binary (-b) resp. all (-bb) files.

       -B     [when compiled with UNIXBACKUP defined] save a backup copy of each overwritten file. The backup
              file is gets the name of the target file with a tilde and optionally a unique sequence number (up
              to 5 digits) appended.  The sequence number is applied whenever another file with the original
              name plus tilde already exists.  When used together with the "overwrite all" option -o, numbered
              backup files are never created. In this case, all backup files are named as the original file
              with an appended tilde, existing backup files are deleted without notice.  This feature works
              similarly to the default behavior of emacs(1) in many locations.

              Example: the old copy of 'foo'is renamed to 'foo~'.

              Warning: Users should be aware that the -B option does not prevent loss of existing data under
              all circumstances.  For example, when unzip is run in overwrite-all mode, an existing 'foo~'
              file is deleted before unzip attempts to rename 'foo' to 'foo~'.  When this rename attempt
              fails (because of a file locks, insufficient privileges, or ...), the extraction of 'foo~' gets
              cancelled, but the old backup file is already lost.  A similar scenario takes place when the
              sequence number range for numbered backup files gets exhausted (99999, or 65535 for 16-bit
              systems).  In this case, the backup file with the maximum sequence number is deleted and replaced
              by the new backup version without notice.

       -C     use case-insensitive matching for the selection of archive entries from the command-line list of
              extract selection patterns.  unzip’s philosophy is 'you get what you ask for' (this is also
              responsible for the -L/-U change; see the relevant options below).  Because some file systems are
              fully case-sensitive (notably those under the Unix Operating System) and because both ZIP
              archives and unzip itself are portable across platforms, unzip’s default behavior is to match
              both wildcard and literal filenames case-sensitively.  That is, specifying 'makefile' on the
              command line will only match 'makefile' in the archive, not 'Makefile' or 'MAKEFILE' (and
              similarly for wildcard specifications).  Since this does not correspond to the behavior of many
              other operating/file systems (for example, OS/2 HPFS, which preserves mixed case but is not
              sensitive to it), the -C option may be used to force all filename matches to be case-insensitive.
              In the example above, all three files would then match 'makefile' (or 'make*', or similar).
              The -C option affects file specs in both the normal file list and the excluded-file list (xlist).

              Please note that the -C option does neither affect the search for the zipfile(s) nor the matching
              of archive entries to existing files on the extraction path.  On a case-sensitive file system,
              unzip will never try to overwrite a file 'FOO' when extracting an entry 'foo'!

       -D     skip restoration of timestamps for extracted items.  Normally, unzip tries to restore all meta-
              information for extracted items that are supplied in the Zip archive (and do not require
              privileges or impose a security risk).  By specifying -D, unzip is told to suppress restoration
              of timestamps for directories explicitly created from Zip archive entries.  This option only
              applies to ports that support setting timestamps for directories (currently ATheOS, BeOS, MacOS,
              OS/2, Unix, VMS, Win32, for other unzip ports, -D has no effect).  The duplicated option -DD
              forces suppression of timestamp restoration for all extracted entries (files and directories).
              This option results in setting the timestamps for all extracted entries to the current time.

              On VMS, the default setting for this option is -D for consistency with the behaviour of BACKUP:
              file timestamps are restored, timestamps of extracted directories are left at the current time.
              To enable restoration of directory timestamps, the negated option --D should be specified.  On
              VMS, the option -D disables timestamp restoration for all extracted Zip archive items.  (Here, a
              single -D on the command line combines with the default -D to do what an explicit -DD does on
              other systems.)

       -F     [Acorn only] suppress removal of NFS filetype extension from stored filenames.

       -F     [non-Acorn systems supporting long filenames with embedded commas, and only if compiled with
              ACORN_FTYPE_NFS defined] translate filetype information from ACORN RISC OS extra field blocks
              into a NFS filetype extension and append it to the names of the extracted files.  (When the
              stored filename appears to already have an appended NFS filetype extension, it is replaced by the
              info from the extra field.)

       -j     junk paths.  The archive’s directory structure is not recreated; all files are deposited in the
              extraction directory (by default, the current one).

       -J     [BeOS only] junk file attributes.  The file’s BeOS file attributes are not restored, just the
              file’s data.

       -K     [AtheOS, BeOS, Unix only] retain SUID/SGID/Tacky file attributes.  Without this flag, these
              attribute bits are cleared for security reasons.

       -L     convert to lowercase any filename originating on an uppercase-only Operating System or file
              system.  (This was unzip’s default behavior in releases prior to 5.11; the new default behavior
              is identical to the old behavior with the -U option, which is now obsolete and will be removed in
              a future release.)  Depending on the archiver, files archived under single-case file systems
              (VMS, old MS-DOS FAT, etc.) may be stored as all-uppercase names; this can be ugly or
              inconvenient when extracting to a case-preserving file system such as OS/2 HPFS or a case-
              sensitive one such as under Unix.  By default unzip lists and extracts such filenames exactly as
              they're stored (excepting truncation, conversion of unsupported characters, etc.); this option
              causes the names of all files from certain systems to be converted to lowercase.  The -LL option
              forces conversion of every filename to lowercase, regardless of the originating file system.

       -M     pipe all output through an internal pager similar to the Unix more(1) command.  At the end of a
              screenful of output, unzip pauses with a '--More--' prompt; the next screenful may be viewed by
              pressing the Enter (Return) key or the space bar.  unzip can be terminated by pressing the 'q'
              key and, on some systems, the Enter/Return key.  Unlike Unix more(1), there is no forward-
              searching or editing capability.  Also, unzip doesn’t notice if long lines wrap at the edge of
              the screen, effectively resulting in the printing of two or more lines and the likelihood that
              some text will scroll off the top of the screen before being viewed.  On some systems the number
              of available lines on the screen is not detected, in which case unzip assumes the height is 24
              lines.

       -n     never overwrite existing files.  If a file already exists, skip the extraction of that file
              without prompting.  By default unzip queries before extracting any file that already exists; the
              user may choose to overwrite only the current file, overwrite all files, skip extraction of the
              current file, skip extraction of all existing files, or rename the current file.

       -N     [Amiga] extract file comments as Amiga filenotes.  File comments are created with the -c option
              of zip(1L), or with the -N option of the Amiga port of zip(1L), which stores filenotes as
              comments.

       -o     overwrite existing files without prompting.  This is a dangerous option, so use it with care.
              (It is often used with -f, however, and is the only way to overwrite directory EAs under OS/2.)

       -P password
              use password to decrypt encrypted zipfile entries (if any).  THIS IS INSECURE!  Many multi-user
              Operating Systems provide ways for any user to see the current command line of any other user;
              even on stand-alone systems there is always the threat of over-the-shoulder peeking.  Storing the
              plaintext password as part of a command line in an automated script is even worse.  Whenever
              possible, use the non-echoing, interactive prompt to enter passwords.  (And where security is
              truly important, use strong encryption such as Pretty Good Privacy instead of the relatively weak
              encryption provided by standard zipfile utilities.)

       -q     perform operations quietly (-qq = even quieter).  Ordinarily unzip prints the names of the files
              it’s extracting or testing, the extraction methods, any file or zipfile comments that may be
              stored in the archive, and possibly a summary when finished with each archive.  The -q[q] options
              suppress the printing of some or all of these messages.

       -s     [OS/2, NT, MS-DOS] convert spaces in filenames to underscores.  Since all PC Operating Systems
              allow spaces in filenames, unzip by default extracts filenames with spaces intact (e.g.,
              'EA DATA. SF').  This can be awkward, however, since MS-DOS in particular does not gracefully
              support spaces in filenames.  Conversion of spaces to underscores can eliminate the awkwardness
              in some cases.

       -S     [VMS] convert text files (-a, -aa) into Stream_LF record format, instead of the text-file
              default, variable-length record format.  (Stream_LF is the default record format of VMS unzip. It
              is applied unless conversion (-a, -aa and/or -b, -bb) is requested or a VMS-specific entry is
              processed.)

       -U     [UNICODE_SUPPORT only] modify or disable UTF-8 handling.  When UNICODE_SUPPORT is available, the
              option -U forces unzip to escape all non-ASCII characters from UTF-8 coded filenames as
              '#Uxxxx' (for UCS-2 characters, or '#Lxxxxxx' for unicode codepoints needing 3 octets).  This
              option is mainly provided for debugging purpose when the fairly new UTF-8 support is suspected to
              mangle up extracted filenames.

              The option -UU allows to entirely disable the recognition of UTF-8 encoded filenames.  The
              handling of filename codings within unzip falls back to the behaviour of previous versions.

              [old, obsolete usage] leave filenames uppercase if created under MS-DOS, VMS, etc.  See -L above.

       -V     retain (VMS) file version numbers.  VMS files can be stored with a version number, in the format
              file.ext;##.  By default the ';##' version numbers are stripped, but this option allows them to
              be retained.  (On file systems that limit filenames to particularly short lengths, the version
              numbers may be truncated or stripped regardless of this option.)

       -W     [only when WILD_STOP_AT_DIR compile-time option enabled] modifies the pattern matching routine so
              that both '?' (single-char wildcard) and '*' (multi-char wildcard) do not match the directory
              separator character `/'.  (The two-character sequence '**' acts as a multi-char wildcard that
              includes the directory separator in its matched characters.)  Examples:

           "*.c" matches "foo.c" but not "mydir/foo.c"
           "**.c" matches both "foo.c" and "mydir/foo.c"
           "*/*.c" matches "bar/foo.c" but not "baz/bar/foo.c"
           "??*/*" matches "ab/foo" and "abc/foo"
                   but not "a/foo" or "a/b/foo"

              This modified behaviour is equivalent to the pattern matching style used by the shells of some of
              UnZip’s supported target OSs (one example is Acorn RISC OS).  This option may not be available on
              systems where the Zip archive’s internal directory separator character `/' is allowed as regular
              character in native Operating System filenames.  (Currently, UnZip uses the same pattern matching
              rules for both wildcard zipfile specifications and zip entry selection patterns in most ports.
              For systems allowing `/' as regular filename character, the -W option would not work as expected
              on a wildcard zipfile specification.)
              
       -X     [VMS, Unix, OS/2, NT, Tandem] restore owner/protection info (UICs and ACL entries) under VMS, or
              user and group info (UID/GID) under Unix, or access control lists (ACLs) under certain network-
              enabled versions of OS/2 (Warp Server with IBM LAN Server/Requester 3.0 to 5.0; Warp Connect with
              IBM Peer 1.0), or security ACLs under Windows NT.  In most cases this will require special system
              privileges, and doubling the option (-XX) under NT instructs unzip to use privileges for
              extraction; but under Unix, for example, a user who belongs to several groups can restore files
              owned by any of those groups, as long as the user IDs match his or her own.  Note that ordinary
              file attributes are always restored--this option applies only to optional, extra ownership info
              available on some Operating Systems.  [NT’s access control lists do not appear to be especially
              compatible with OS/2’s, so no attempt is made at cross-platform portability of access privileges.
              It is not clear under what conditions this would ever be useful anyway.]

       -Y     [VMS] treat archived file name endings of '.nnn' (where 'nnn' is a decimal  number) as if
              they were VMS version numbers (';nnn').  (The default is to treat them as file types.)
              Example:
                   "a.b.3" -> "a.b;3".

       -$     [MS-DOS, OS/2, NT] restore the volume label if the extraction medium is removable (e.g., a
              diskette).  Doubling the option (-$$) allows fixed media (hard disks) to be labelled as well.  By
              default, volume labels are ignored.

       -/ extensions
              [Acorn only] overrides the extension list supplied by Unzip$Ext environment variable. During
              extraction, filename extensions that match one of the items in this extension list are swapped in
              front of the base name of the extracted file.

       -:     [all but Acorn, VM/CMS, MVS, Tandem] allows to extract archive members into locations outside of
              the current ' extraction root folder'. For security reasons, unzip normally removes 'parent
              dir' path components ('../') from the names of extracted file.  This safety feature (new for
              version 5.50) prevents unzip from accidentally writing files to 'sensitive' areas outside the
              active extraction folder tree head.  The -: option lets unzip switch back to its previous, more
              liberal behaviour, to allow exact extraction of (older) archives that used '../' components to
              create multiple directory trees at the level of the current extraction folder.  This option does
              not enable writing explicitly to the root directory ('/').  To achieve this, it is necessary to
              set the extraction target folder to root (e.g. -d / ).  However, when the -: option is specified,
              it is still possible to implicitly write to the root directory by specifying enough '../' path
              components within the zip archive.  Use this option with extreme caution.

       -^     [Unix only] allow control characters in names of extracted ZIP archive entries.  On Unix, a file
              name may contain any (8-bit) character code with the two exception '/' (directory delimiter) and
              NUL (0x00, the C string termination indicator), unless the specific file system has more
              restrictive conventions.  Generally, this allows to embed ASCII control characters (or even
              sophisticated control sequences) in file names, at least on 'native' Unix file systems.  However,
              it may be highly suspicious to make use of this Unix "feature".  Embedded control characters in
              file names might have nasty side effects when displayed on screen by some listing code without
              sufficient filtering.  And, for ordinary users, it may be difficult to handle such file names
              (e.g. when trying to specify it for open, copy, move, or delete operations).  Therefore, unzip
              applies a filter by default that removes potentially dangerous control characters from the
              extracted file names. The -^ option allows to override this filter in the rare case that embedded
              filename control characters are to be intentionally restored.

       -2     [VMS] force unconditionally conversion of file names to ODS2-compatible names.  The default is to
              exploit the destination file system, preserving case and extended file name characters on an ODS5
              destination file system; and applying the ODS2-compatibility file name filtering on an ODS2
              destination file system.

Environment Options

unzip’s default behavior may be modified via options placed in an environment variable. This can be
done with any option, but it is probably most useful with the -a, -L, -C, -q, -o, or -n modifiers: make
unzip auto-convert text files by default, make it convert filenames from uppercase systems to lowercase,
make it match names case-insensitively, make it quieter, or make it always overwrite or never overwrite
files as it extracts them. For example, to make unzip act as quietly as possible, only reporting
errors, one would use one of the following commands:

Unix Bourne shell:
UNZIP=-qq; export UNZIP

Unix C shell:
setenv UNZIP -qq

Windows NT:
set UNZIP=-qq

VMS (quotes for lowercase):
define UNZIP_OPTS "-qq"

Environment options are, in effect, considered to be just like any other command-line options, except
that they are effectively the first options on the command line. To override an environment option, one
may use the 'minus operator' to remove it. For instance, to override one of the quiet-flags in the
example above, use the command

unzip --q[other options] zipfile

The first hyphen is the normal switch character, and the second is a minus sign, acting on the q option.
Thus the effect here is to cancel one quantum of quietness. To cancel both quiet flags, two (or more)
minuses may be used:

unzip -t--q zipfile
unzip ---qt zipfile

(the two are equivalent). This may seem awkward or confusing, but it is reasonably intuitive: just
ignore the first hyphen and go from there. It is also consistent with the behavior of Unix nice(1).

As suggested by the examples above, the default variable names are UNZIP_OPTS for VMS (where the symbol
used to install unzip as a foreign command would otherwise be confused with the environment variable),
and UNZIP for all other Operating Systems. For compatibility with zip(1L), UNZIPOPT is also accepted
(don’t ask). If both UNZIP and UNZIPOPT are defined, however, UNZIP takes precedence. unzip’s
diagnostic option (-v with no zipfile name) can be used to check the values of all four possible unzip
and zipinfo environment variables.

The timezone variable (TZ) should be set according to the local timezone in order for the -f and -u to
operate correctly. See the description of -f above for details. This variable may also be necessary to
get timestamps of extracted files to be set correctly. The WIN32 (Win9x/ME/NT4/2K/XP/2K3) port of unzip
gets the timezone configuration from the registry, assuming it is correctly set in the Control Panel.
The TZ variable is ignored for this port.

Encrypted archives are fully supported by Info-ZIP software, but due to United States export restrictions, de-/encryption support might be disabled in your compiled binary. However, since spring 2000, US export restrictions have been liberated, and our source archives do now include full cryptcode. In case you need binary distributions with crypt support enabled, see the file 'WHERE' in any Info-ZIP source or binary distribution for locations both inside and outside the US. Some compiled versions of unzip may not support decryption. To check a version for crypt support, either attempt to test or extract an encrypted archive, or else check unzip’s diagnostic screen (see the -v option above) for '[decryption]' as one of the special compilation options.

As noted above, the -P option may be used to supply a password on the command line, but at a cost in security. The preferred decryption method is simply to extract normally; if a zipfile member is encrypted, unzip will prompt for the password without echoing what is typed. unzip continues to use the same password as long as it appears to be valid, by testing a 12-byte header on each file. The correct password will always check out against the header, but there is a 1-in-256 chance that an incorrect password will as well. (This is a security feature of the PKWARE zipfile format; it helps prevent brute-force attacks that might otherwise gain a large speed advantage by testing only the header.) In the case that an incorrect password is given but it passes the header test anyway, either an incorrect CRC will be generated for the extracted data or else unzip will fail during the extraction because the 'dzecrypted' bytes do not constitute a valid compressed data stream. I

f the first password fails the header check on some file, unzip will prompt for another password, and so on until all files are extracted. If a password is not known, entering a null password (that is, just a carriage return or 'Enter') is taken as a signal to skip all further prompting. Only unencrypted files in the archive(s) will thereafter be extracted. (In fact, that’s not quite true; older versions of zip(1L) and zipcloak(1L) allowed null passwords, so unzip checks each encrypted file to see if the null password works. This may result in 'false positives' and extraction errors, as noted above.)

Archives encrypted with 8-bit passwords (for example, passwords with accented European characters) may not be portable across systems and/or other archivers. This problem stems from the use of multiple encoding methods for such characters, including Latin-1 (ISO 8859-1) and OEM code page 850. DOS PKZIP 2.04g uses the OEM code page; Windows PKZIP 2.50 uses Latin-1 (and is therefore incompatible with DOS PKZIP); Info-ZIP uses the OEM code page on DOS, OS/2 and Win3.x ports but ISO coding (Latin-1 etc.) everywhere else; and Nico Mak’s WinZip 6.x does not allow 8-bit passwords at all. UnZip 5.3 (or newer) attempts to use the default character set first (e.g., Latin-1), followed by the alternate one (e.g., OEM code page) to test passwords.

On EBCDIC systems, if both of these fail, EBCDIC encoding will be tested as a last resort. (EBCDIC is not tested on non-EBCDIC systems, because there are no known archivers that encrypt using EBCDIC encoding.) ISO character encodings other than Latin-1 are not supported.

The new addition of (partially) Unicode (resp. UTF-8) support in UnZip 6.0 has not yet been adapted to the encryption password handling in unzip.

On systems that use UTF-8 as native character encoding, unzip simply tries decryption with the native UTF-8 encoded password; the built-in attempts to check the password in translated encoding have not yet been adapted for UTF-8 support and will consequently fail.

Examples

To use unzip to extract all members of the archive letters.zip into the current directory and
subdirectories below it, creating any subdirectories as necessary:

unzip letters

To extract all members of letters.zip into the current directory only:

unzip -j letters

To test letters.zip, printing only a summary message indicating whether the archive is OK or not:

unzip -tq letters

To test all zipfiles in the current directory, printing only the summaries:

unzip -tq \*.zip

(The backslash before the asterisk is only required if the shell expands wildcards, as in Unix; double
quotes could have been used instead, as in the source examples below.)  To extract to standard output
all members of letters.zip whose names end in .tex, auto-converting to the local end-of-line convention
and piping the output into more(1):

unzip -ca letters \*.tex | more

To extract the binary file paper1.dvi to standard output and pipe it to a printing program:

unzip -p articles paper1.dvi | dvips

To extract all FORTRAN and C source files--*.f, *.c, *.h, and Makefile--into the /tmp directory:

unzip source.zip "*.[fch]" Makefile -d /tmp

(the double quotes are necessary only in Unix and only if globbing is turned on). To extract all
FORTRAN and C source files, regardless of case (e.g., both *.c and *.C, and any makefile, Makefile,
MAKEFILE or similar):

unzip -C source.zip "*.[fch]" makefile -d /tmp

To extract any such files but convert any uppercase MS-DOS or VMS names to lowercase and convert the
line-endings of all of the files to the local standard (without respect to any files that might be
marked 'binary'):

unzip -aaCL source.zip "*.[fch]" makefile -d /tmp

To extract only newer versions of the files already in the current directory, without querying (NOTE:
be careful of unzipping in one timezone a zipfile created in another--ZIP archives other than those
created by Zip 2.1 or later contain no timezone information, and a 'newer' file from an eastern
timezone may, in fact, be older):

unzip -fo sources

To extract newer versions of the files already in the current directory and to create any files not
already there (same caveat as previous example):

unzip -uo sources

To display a diagnostic screen showing which unzip and zipinfo options are stored in environment
variables, whether decryption support was compiled in, the compiler with which unzip was compiled, etc.:

unzip -v

In the last five examples, assume that UNZIP or UNZIP_OPTS is set to -q. To do a singly quiet listing:

unzip -l file.zip

To do a doubly quiet listing:

unzip -ql file.zip

(Note that the '.zip' is generally not necessary.)

To do a standard listing:

unzip --ql file.zip
or
unzip -l-q file.zip
or
unzip -l--q file.zip

(Extra minuses in options don’t hurt.)

The current maintainer, being a lazy sort, finds it very useful to define a pair of aliases: tt for 'unzip -tq' and ii for 'unzip -Z' (or 'zipinfo'). One may then simply type 'tt zipfile' to test an archive, something that is worth making a habit of doing. With luck unzip will report 'No errors detected in compressed data of zipfile.zip', after which one may breathe a sigh of relief.

The maintainer also finds it useful to set the UNZIP environment variable to '-aL' and is tempted to add '-C' as well. His ZIPINFO variable is set to '-z'.

PATTERN MATCHING

 

Exit codes:

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.

      1      one or more warning errors were encountered, but processing completed successfully anyway.
             This includes zipfiles where one or more files was skipped due to unsupported compression
             method or encryption with an unknown password.

      2      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.

      3      a severe error in the zipfile format was detected.  Processing probably failed
             immediately.

      4      unzip was unable to allocate memory for one or more buffers during program initialization.

      5      unzip was unable to allocate memory or unable to obtain a tty to read the decryption
             password(s).

      6      unzip was unable to allocate memory during decompression to disk.

      7      unzip was unable to allocate memory during in-memory decompression.

      8      [currently not used]

      9      the specified zipfiles were not found.

      10     invalid options were specified on the command line.

      11     no matching files were found.

      50     the disk is (or was) full during extraction.

      51     the end of the ZIP archive was encountered prematurely.
      
      80     the user aborted unzip prematurely with control-C (or similar)

      81     testing or extraction of one or more files failed due to unsupported compression methods
             or unsupported decryption.

      82     no files were found due to bad decryption password(s).  (If even one file is successfully
             processed, however, the exit status is 1.)

Bugs

Multi-part archives are not yet supported, except in conjunction with zip. (All parts must be concatenated together in order, and then 'zip -F' (for zip 2.x) or 'zip -FF' (for zip 3.x) must be performed on the concatenated archive in order to 'fix' it. Also, zip 3.0 and later can combine multi-part (split) archives into a combined single-file archive using 'zip -s- inarchive -O outarchive'. See the zip 3 manual page for more information.) This will definitely be corrected in the next major release.

Archives read from standard input are not yet supported, except with funzip (and then only the first member of the archive can be extracted).

Archives encrypted with 8-bit passwords (e.g., passwords with accented European characters) may not be portable across systems and/or other archivers. See the discussion in DECRYPTION above.

unzip’s -M ('more') option tries to take into account automatic wrapping of long lines. However, the code may fail to detect the correct wrapping locations. First, TAB characters (and similar control sequences) are not taken into account, they are handled as ordinary printable characters. Second, depending on the actual system / OS port, unzip may not detect the true screen geometry but rather rely on "commonly used" default dimensions. The correct handling of tabs would require the implementation of a query for the actual tabulator setup on the output console.

Dates, times and permissions of stored directories are not restored except under Unix. (On Windows NT and successors, timestamps are now restored.)

[MS-DOS] When extracting or testing files from an archive on a defective floppy diskette, if the 'Fail' option is chosen from DOS’s 'Abort, Retry, Fail?' message, older versions of unzip may hang the system, requiring a reboot. This problem appears to be fixed, but control-C (or control-Break) can still be used to terminate unzip.

Under DEC Ultrix, unzip would sometimes fail on long zipfiles (bad CRC, not always reproducible). This was apparently due either to a hardware bug (cache memory) or an Operating System bug (improper handling of page faults?). Since Ultrix has been abandoned in favor of Digital Unix (OSF/1), this may not be an issue anymore.

[Unix] Unix special files such as FIFO buffers (named pipes), block devices and character devices are not restored even if they are somehow represented in the zipfile, nor are hard-linked files relinked. Basically the only file types restored by unzip are regular files, directories and symbolic (soft) links.

[OS/2] Extended attributes for existing directories are only updated if the -o ('overwrite all') option is given. This is a limitation of the Operating System; because directories only have a creation time associated with them, unzip has no way to determine whether the stored attributes are newer or older than those on disk. In practice this may mean a two-pass approach is required: first unpack the archive normally (with or without freshening/updating existing files), then overwrite just the directory entries (e.g., 'unzip -o foo */').

[VMS] When extracting to another directory, only the [.foo] syntax is accepted for the -d option; the simple Unix foo syntax is silently ignored (as is the less common VMS foo.dir syntax).

[VMS] When the file being extracted already exists, unzip’s query only allows skipping, overwriting or renaming; there should additionally be a choice for creating a new version of the file. In fact, the 'overwrite' choice does create a new version; the old version is not overwritten or deleted.

“He can compress the most words into the smallest ideas of any man I ever met” ~ Abraham Lincoln

Related macOS commands

Local man page: unzip - Command line help page on your local machine.
cpio - Copy files to and from archives.
gzip - Compress or decompress files.
tar - Store, list or extract files in an archive.
zip - Package and compress (archive) files.
zipcloak, zipnote , zipsplit (see man page)
compress(1), shar(1L), gzip(1L)


 
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