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UNZIP(1L)                                                            UNZIP(1L)

       unzip - list, test and extract compressed files in a ZIP archive

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

       unzip  will  list,  test,  or  extract files from a ZIP archive, commonly found on MS-DOS systems.  The default
       behavior (with no options) is to extract into the current directory (and subdirectories  below  it)  all  files
       from the specified ZIP archive.  A companion program, zip(1L), creates ZIP archives; both programs are compati-
       ble with archives created by PKWARE's PKZIP and PKUNZIP for MS-DOS, but in many cases the  program  options  or
       default behaviors differ.

              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 char-
                     acter,  a  hyphen, and an ending character.  If an exclamation point or a caret ('!' or '^') fol-
                     lows 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.

              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  con-
              catenated 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.

       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  Day-
              light 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  com-
              ments  (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  corre-
              sponds  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 addi-
              tion 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  speci-
              fied  with  no other options, -v lists archive files verbosely, adding to the basic -l info the compres-
              sion 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  vari-
              ables  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  imple-
              mented but will be in future releases.

       -z     display only the archive comment.

       -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 cir-
              cumstances.  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 maxi-
              mum 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-informa-
              tion 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.)

       -E     [MacOS only] display contents of MacOS extra field during restore operation.

       -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.)

       -i     [MacOS only] ignore filenames stored in MacOS extra fields. Instead, the most compatible filename stored
              in the generic part of the entry's header is used.

       -j     junk  paths.  The archive's directory structure is not recreated; all files are deposited in the extrac-
              tion 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

       -J     [MacOS only] ignore MacOS extra fields.  All Macintosh specific info is skipped. Data-fork and resource-
              fork are restored as separate files.

       -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 char-
              acters, etc.); this option causes the names of all files from certain systems to be converted to  lower-
              case.   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  screen-
              ful 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 capabil-
              ity.  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  operat-
              ing  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 util-

       -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  print-
              ing 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 file-
              names.  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, vari-
              able-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 char-
              acter '/'.  (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 sys-
              tems 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 speci-

       -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 ver-
              sions 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 portabil-
              ity 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)  pre-
              vents  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 dis-
              played 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 desti-
              nation file system; and applying the ODS2-compatibility file name filtering on an ODS2 destination  file

       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-con-
       vert  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 follow-
       ing commands:

         Unix Bourne shell:
              UNZIP=-qq; export UNZIP

         Unix C shell:
              setenv UNZIP -qq

         OS/2 or MS-DOS:
              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 crypt code.   In  case  you  need
       binary  distributions  with crypt support enabled, see the file ''WHERE'' in any Info-ZIP source or binary dis-
       tribution 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  secu-
       rity  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 ''decrypted'' bytes do  not  constitute  a  valid  compressed  data

       If  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  zip-
       cloak(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  sys-
       tems,  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 encod-
       ings  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 con-
       sequently fail.

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

           unzip letters

       To extract all members of into the current directory only:

           unzip -j letters

       To test, 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 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 "*.[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 "*.[fch]" makefile -d /tmp

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

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

       To extract only newer versions of the files already in the current directory, without querying (NOTE:  be care-
       ful 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

           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

       To do a doubly quiet listing:

           unzip -ql

       (Note that the ''.zip'' is generally not necessary.)  To do a standard listing:

           unzip --ql
           unzip -l-q
           unzip -l--q
       (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  com-
       pressed data of,'' 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''.

       The exit status (or error level) approximates the exit codes defined by PKWARE and takes on the following  val-
       ues, 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  pro-
                     cessed, however, the exit status is 1.)

       VMS interprets standard Unix (or PC) return values as other, scarier-looking things, so unzip instead maps them
       into VMS-style status codes.  The current mapping is as follows:   1 (success) for normal exit, 0x7fff0001  for
       warning errors, and (0x7fff000? + 16*normal_unzip_exit_status) for all other errors, where the '?' is 2 (error)
       for unzip values 2, 9-11 and 80-82, and 4 (fatal error) for the remaining ones (3-8,  50,  51).   In  addition,
       there  is a compilation option to expand upon this behavior:  defining RETURN_CODES results in a human-readable
       explanation of what the error status means.

       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 con-
       catenated 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 suc-
       cessors, 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 renam-
       ing; 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.

       funzip(1L), zip(1L), zipcloak(1L), zipgrep(1L), zipinfo(1L), zipnote(1L), zipsplit(1L)

       The Info-ZIP home page is currently at

       The primary Info-ZIP authors (current semi-active members of the Zip-Bugs workgroup) are:  Ed Gordon (Zip, gen-
       eral maintenance, shared code, Zip64, Win32, Unix, Unicode); Christian Spieler (UnZip maintenance coordination,
       VMS,  MS-DOS,  Win32,  shared  code,  general  Zip and UnZip integration and optimization); Onno van der Linden
       (Zip); Mike White (Win32, Windows GUI, Windows DLLs); Kai Uwe Rommel (OS/2, Win32);  Steven  M.  Schweda  (VMS,
       Unix,  support  of  new  features);  Paul  Kienitz  (Amiga, Win32, Unicode); Chris Herborth (BeOS, QNX, Atari);
       Jonathan Hudson (SMS/QDOS); Sergio Monesi (Acorn RISC OS); Harald Denker  (Atari,  MVS);  John  Bush  (Solaris,
       Amiga);  Hunter  Goatley  (VMS,  Info-ZIP  Site maintenance); Steve Salisbury (Win32); Steve Miller (Windows CE
       GUI), Johnny Lee (MS-DOS, Win32, Zip64); and Dave Smith (Tandem NSK).

       The following people were former members of the Info-ZIP development group and provided major contributions  to
       key  parts  of  the  current code: Greg ''Cave Newt'' Roelofs (UnZip, unshrink decompression); Jean-loup Gailly
       (deflate compression); Mark Adler (inflate decompression, fUnZip).

       The author of the original unzip code upon which Info-ZIP's was based is Samuel H. Smith; Carl Mascott did  the
       first  Unix  port;  and  David  P.  Kirschbaum organized and led Info-ZIP in its early days with Keith Petersen
       hosting the original mailing list at WSMR-SimTel20.  The full list of contributors to  UnZip  has  grown  quite
       large; please refer to the CONTRIBS file in the UnZip source distribution for a relatively complete version.

       v1.2   15 Mar 89   Samuel H. Smith
       v2.0    9 Sep 89   Samuel H. Smith
       v2.x   fall 1989   many Usenet contributors
       v3.0    1 May 90   Info-ZIP (DPK, consolidator)
       v3.1   15 Aug 90   Info-ZIP (DPK, consolidator)
       v4.0    1 Dec 90   Info-ZIP (GRR, maintainer)
       v4.1   12 May 91   Info-ZIP
       v4.2   20 Mar 92   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.0   21 Aug 92   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.01  15 Jan 93   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.1    7 Feb 94   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.11   2 Aug 94   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.12  28 Aug 94   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.2   30 Apr 96   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.3   22 Apr 97   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.31  31 May 97   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.32   3 Nov 97   Info-ZIP (Zip-Bugs subgroup, GRR)
       v5.4   28 Nov 98   Info-ZIP (Zip-Bugs subgroup, SPC)
       v5.41  16 Apr 00   Info-ZIP (Zip-Bugs subgroup, SPC)
       v5.42  14 Jan 01   Info-ZIP (Zip-Bugs subgroup, SPC)
       v5.5   17 Feb 02   Info-ZIP (Zip-Bugs subgroup, SPC)
       v5.51  22 May 04   Info-ZIP (Zip-Bugs subgroup, SPC)
       v5.52  28 Feb 05   Info-ZIP (Zip-Bugs subgroup, SPC)
       v6.0   20 Apr 09   Info-ZIP (Zip-Bugs subgroup, SPC)

Info-ZIP                     20 April 2009 (v6.0)                    UNZIP(1L)