unzip.txt

UNZIP(1L)                                                            UNZIP(1L)

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

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

DESCRIPTION
       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 compatible with  archives  cre-
       ated  by  PKWARE's  PKZIP and PKUNZIP for MS-DOS, but in many cases the
       program options or default behaviors differ.

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

              *      matches a sequence of 0 or more characters

              ?      matches exactly 1 character

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

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

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

       [-x xfile(s)]
              An optional list of archive members to be excluded from process-
              ing.  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 direc-
              tory; 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 nor-
              mal 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  direc-
              tory.

OPTIONS
       Note  that,  in  order  to  support obsolescent hardware, unzip's usage
       screen is limited to 22 or 23 lines and should therefore be  considered
       only  a  reminder  of  the basic unzip syntax rather than an exhaustive
       list of all possible flags.  The exhaustive list follows:

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

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

       -c     extract files to stdout/screen (``CRT'').  This option is  simi-
              lar  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 oper-
              ating 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-for-
              mat  times  (always in GMT/UTC) and the necessity to compare the
              two.  A typical TZ value is ``PST8PDT'' (US  Pacific  time  with
              automatic  adjustment  for  Daylight  Savings  Time  or ``summer
              time'').

       -l     list archive files (short format).  The names, uncompressed file
              sizes  and  modification  dates and times of the specified files
              are printed, along with totals  for  all  files  specified.   If
              UnZip  was  compiled  with  OS2_EAS  defined, the -l option also
              lists columns for the sizes of stored OS/2  extended  attributes
              (EAs)  and  OS/2  access control lists (ACLs).  In addition, the
              zipfile comment and individual file comments (if any)  are  dis-
              played.   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 pre-
              fixed 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 zip-
              file 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 addi-
              tional 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 sepa-
              rate manual.)  When no zipfile is specified (that is,  the  com-
              plete  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  modi-
              fier  it  works  in conjunction with other options (e.g., -t) to
              produce more verbose or debugging output; this is not yet  fully
              implemented but will be in future releases.

       -z     display only the archive comment.

MODIFIERS
       -a     convert  text files.  Ordinarily all files are extracted exactly
              as they are stored (as ``binary'' files).  The -a option  causes
              files  identified by zip as text files (those with the `t' label
              in zipinfo  listings,  rather  than  `b')  to  be  automatically
              extracted  as such, converting line endings, end-of-file charac-
              ters 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 stan-
              dard 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 when-
              ever 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  pre-
              vent  loss  of existing data under all circumstances.  For exam-
              ple, 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  pat-
              terns.  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-sensi-
              tive (notably those under the Unix operating system) and because
              both  ZIP  archives  and  unzip itself are portable across plat-
              forms, unzip's default behavior is to match  both  wildcard  and
              literal filenames case-sensitively.  That is, specifying ``make-
              file'' 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 exist-
              ing files on the extraction path.  On a case-sensitive file sys-
              tem, 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 privi-
              leges 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  consis-
              tency   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 com-
              mas, and only if compiled with ACORN_FTYPE_NFS  defined]  trans-
              late  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-sensi-
              tive  one  such  as  under  Unix.   By  default  unzip lists and
              extracts such filenames exactly  as  they're  stored  (excepting
              truncation,  conversion  of  unsupported characters, etc.); this
              option causes the names of all files from certain systems to  be
              converted  to  lowercase.   The  -LL option forces conversion of
              every filename to lowercase, regardless of the originating  file
              system.

       -M     pipe  all  output  through an internal pager similar to the Unix
              more(1) command.  At the end of a  screenful  of  output,  unzip
              pauses  with  a  ``--More--''  prompt; the next screenful may be
              viewed by pressing the Enter (Return)  key  or  the  space  bar.
              unzip  can  be terminated by pressing the ``q'' key and, on some
              systems, the Enter/Return key.  Unlike Unix more(1), there is no
              forward-searching  or  editing  capability.  Also, unzip doesn't
              notice if long lines wrap at the edge of the screen, effectively
              resulting  in  the printing of two or more lines and the likeli-
              hood 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  com-
              ments.

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

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

       -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  awkward-
              ness 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  sus-
              pected 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] modi-
              fies the pattern matching routine so that both `?'  (single-char
              wildcard)  and `*' (multi-char wildcard) do not match the direc-
              tory  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  avail-
              able on systems where the Zip archive's internal directory sepa-
              rator character `/' is allowed as regular  character  in  native
              operating  system  filenames.   (Currently,  UnZip uses the same
              pattern matching rules for both wildcard zipfile  specifications
              and  zip  entry  selection  patterns in most ports.  For systems
              allowing `/' as regular filename character, the -W option  would
              not work as expected on a wildcard zipfile specification.)

       -X     [VMS,  Unix,  OS/2,  NT,  Tandem]  restore owner/protection info
              (UICs and ACL  entries)  under  VMS,  or  user  and  group  info
              (UID/GID)  under Unix, or access control lists (ACLs) under cer-
              tain 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  num-
              bers  (``;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.   Gener-
              ally,  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 suspi-
              cious 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 filter-
              ing.   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  destina-
              tion file system, preserving case and extended file name charac-
              ters on an  ODS5  destination  file  system;  and  applying  the
              ODS2-compatibility  file  name  filtering on an ODS2 destination
              file system.

ENVIRONMENT OPTIONS
       unzip's default behavior may be modified via options placed in an envi-
       ronment 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 pos-
       sible,  only  reporting errors, one would use one of the following com-
       mands:

         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  time-
       zone in order for the -f and -u to operate correctly.  See the descrip-
       tion 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.

DECRYPTION
       Encrypted archives are fully supported by Info-ZIP software, but due to
       United States export restrictions, de-/encryption support might be dis-
       abled 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
       options.

       As noted above, the -P option may be used to supply a password  on  the
       command  line,  but  at  a  cost in security.  The preferred decryption
       method is simply to extract normally; if a zipfile member is encrypted,
       unzip  will  prompt  for  the  password  without echoing what is typed.
       unzip continues to use the same password as long as it  appears  to  be
       valid,  by testing a 12-byte header on each file.  The correct password
       will always check out against the  header,  but  there  is  a  1-in-256
       chance  that  an  incorrect password will as well.  (This is a security
       feature of the PKWARE zipfile  format;  it  helps  prevent  brute-force
       attacks  that  might  otherwise gain a large speed advantage by testing
       only the header.)  In the case that an incorrect password is given  but
       it  passes the header test anyway, either an incorrect CRC will be gen-
       erated 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(1L)
       and zipcloak(1L) allowed null passwords, so unzip checks each encrypted
       file  to  see  if  the null password works.  This may result in ``false
       positives'' and extraction errors, as noted above.)

       Archives encrypted with 8-bit passwords (for  example,  passwords  with
       accented European characters) may not be portable across systems and/or
       other archivers.  This problem stems from the use of multiple  encoding
       methods  for  such  characters,  including Latin-1 (ISO 8859-1) and OEM
       code page 850.  DOS PKZIP 2.04g uses the OEM code page;  Windows  PKZIP
       2.50 uses Latin-1 (and is therefore incompatible with DOS PKZIP); Info-
       ZIP uses the OEM code page on DOS, OS/2 and Win3.x ports but ISO coding
       (Latin-1  etc.)  everywhere  else;  and  Nico Mak's WinZip 6.x does not
       allow 8-bit passwords at all.  UnZip 5.3 (or newer) attempts to use the
       default  character set first (e.g., Latin-1), followed by the alternate
       one (e.g., OEM code page) to test passwords.   On  EBCDIC  systems,  if
       both  of  these  fail, EBCDIC encoding will be tested as a last resort.
       (EBCDIC is not tested on non-EBCDIC systems, because there are no known
       archivers that encrypt using EBCDIC encoding.)  ISO character encodings
       other than Latin-1 are not supported.  The new addition of  (partially)
       Unicode (resp.  UTF-8) support in UnZip 6.0 has not yet been adapted to
       the encryption password handling in unzip.  On systems that  use  UTF-8
       as  native  character  encoding, unzip simply tries decryption with the
       native UTF-8 encoded password; the built-in attempts to check the pass-
       word in translated encoding have not yet been adapted for UTF-8 support
       and will consequently fail.

EXAMPLES
       To use unzip to extract all members of the archive letters.zip into the
       current directory and subdirectories below it, creating any subdirecto-
       ries 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 sum-
       maries:

           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 out-
       put 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  Make-
       file--into the /tmp directory:

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

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

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

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

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

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

           unzip -fo sources

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

           unzip -uo sources

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

           unzip -v

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

           unzip -l file.zip

       To do a doubly quiet listing:

           unzip -ql file.zip

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

           unzip --ql file.zip
       or
           unzip -l-q file.zip
       or
           unzip -l--q file.zip
       (Extra minuses in options don't hurt.)

TIPS
       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 zip-
       file.zip,'' after which one may breathe a sigh of relief.

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

DIAGNOSTICS
       The exit status (or error level) approximates the exit codes defined by
       PKWARE and takes on the following values, except under VMS:

              0      normal; no errors or warnings detected.

              1      one or more warning errors were encountered, but process-
                     ing completed successfully anyway.   This  includes  zip-
                     files  where  one or more files was skipped due to unsup-
                     ported compression method or encryption with  an  unknown
                     password.

              2      a generic error in the zipfile format was detected.  Pro-
                     cessing may have completed successfully anyway; some bro-
                     ken zipfiles created by other archivers have simple work-
                     arounds.

              3      a severe error in the zipfile format was detected.   Pro-
                     cessing 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 decryp-
                     tion.

              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*nor-
       mal_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 remain-
       ing 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.

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

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

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

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

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

       [MS-DOS]  When  extracting or testing files from an archive on a defec-
       tive 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 con-
       trol-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.  Basi-
       cally the only file types restored by unzip are regular files, directo-
       ries 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  nor-
       mally  (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  ``over-
       write''  choice does create a new version; the old version is not over-
       written or deleted.

SEE ALSO
       funzip(1L),  zip(1L),  zipcloak(1L),  zipgrep(1L),  zipinfo(1L),   zip-
       note(1L), zipsplit(1L)

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

AUTHORS
       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,
       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.

VERSIONS
       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)