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       -:     [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