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(1),
   creates ZIP  archives;  both  programs  are  compatible  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 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.

          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.


   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(1) mode.  If the first option on the command line is -Z,
          the remaining options are taken to be zipinfo(1)  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

   -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(1)
          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

   -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  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.)

   -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 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.

   -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  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

   -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(1), or with the -N  option
          of the Amiga port of zip(1), 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

   -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

   -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

   -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.


   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

     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(1),
   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 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

   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 ``decrypted'' bytes do not  constitute  a  valid
   compressed data stream.

   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(1)
   and  zipcloak(1) 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.


   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

   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

   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

   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

   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

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


   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

          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

          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

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

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

   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

   [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.


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


   The Info-ZIP home page is currently at
   ftp://ftp.info-zip.org/pub/infozip/ .


   The primary Info-ZIP authors (current semi-active members of  the  Zip-
   Bugs workgroup) are:  Ed Gordon (Zip, general 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,

   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)


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