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UNZIP(1L)							     UNZIP(1L)

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

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

       unzip will list, test, or extract files from a  ZIP  archive,  commonly
       found  on MS-DOS systems.  The default behavior (with no options) is to
       extract into the current directory (and subdirectories  below  it)  all
       files  from  the	 specified ZIP archive.	 A companion program, zip(1L),
       creates ZIP archives; both programs are 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.

	      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.

	      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 exeptions see the option -W, this option may be
	      used to exclude any files that are in subdirectories.  For exam-
	      ple,  ''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-

       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

       -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

       -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     be  verbose  or  print 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, compres-
	      sion 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 encryped compressed data
	      stream for zipfile entries is reported by the more verbose  zip-
	      info(1L)	reports, see the separate manual.)  When no zipfile is
	      specified (that is,  the	complete  command  is  simply  ''unzip
	      -v''),  a diagnostic screen is printed.  In addition to the nor-
	      mal 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  com-
	      piled,  as  well as (possibly) the hardware on which it was com-
	      piled, 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 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.

       -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     [Unix only, and only if compiled with UNIXBACKUP defined] save a
	      backup  copy  of	each  overwritten  file	 with a tilde appended
	      (e.g., the old copy of ''foo'' is renamed to ''foo~'').  This is
	      similar to the default behavior of emacs(1) in many locations.

       -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 -L 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''!

       -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

       -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-

       -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

       -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-

       -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.

       -U     (obsolete;  to  be  removed in a future release) 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 interal 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] restore owner/protection info (UICs) under
	      VMS, or user and group info (UID/GID) under Unix, or access con-
	      trol lists (ACLs) under certain network-enabled versions of OS/2
	      (Warp Server with IBM LAN Server/Requester 3.0 to 5.0; Warp Con-
	      nect  with IBM Peer 1.0), or security ACLs under Windows NT.  In
	      most cases this will require special system privileges, and dou-
	      bling  the  option  (-XX) under NT instructs unzip to use privi-
	      leges 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  any-

       -$     [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
	      specifiying  enough  ''../''  path  components  within  the  zip
	      archive.	Use this option with extreme caution.

       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-

	 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.

       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

       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 Latin-1
       everywhere else; and Nico Mak's WinZip 6.x does not allow  8-bit	 pass-
       words at all.  UnZip 5.3 (or newer) attempts to use the default charac-
       ter 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.

       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-

	   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

	   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  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''.

       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

	      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-

	      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

	      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  decryp-

	      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.

       Multi-part  archives  are not yet supported, except in conjunction with
       zip.  (All parts must be concatenated together in order, and then ''zip
       -F''  must be performed on the concatenated archive in order to ''fix''
       it.)  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 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

       [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	 over-
       write 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.

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

       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); 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, support of new features); Paul Kienitz (Amiga, Win32); Chris Her-
       borth  (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 Salis-
       bury (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)

Info-ZIP		   28 February 2005 (v5.52)		     UNZIP(1L)
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