unzip.txt

zip压缩

ENVIRONMENT OPTIONS
       unzip's  default  behavior  may  be  modified  via options
       placed in an environment variable.  This can be done  with
       any  option,  but  it is probably most useful with the -a,
       -L, -C, -q, -o, or -n modifiers:  make unzip  auto-convert
       text  files  by  default,  make  it convert filenames from
       uppercase systems to lowercase, make it match names  case-
       insensitively,  make  it  quieter, or make it always over-
       write or never overwrite files as it extracts  them.   For
       example,  to  make  unzip act as quietly as possible, only
       reporting errors, one would use one of the following  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

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UNZIP(1L)                                               UNZIP(1L)

           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  con-
       fusing,  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 con-
       fused with the environment variable), and  UNZIP  for  all
       other  operating systems.  For compatibility with zip(1L),
       UNZIPOPT is also accepted (don't ask).  If both UNZIP  and
       UNZIPOPT  are  defined,  however,  UNZIP takes precedence.
       unzip's diagnostic option (-v with no zipfile name) can be
       used  to  check  the values of all four possible unzip and
       zipinfo environment variables.

       The timezone variable (TZ) should be set according to  the
       local  timezone in order for the -f and -u to operate cor-
       rectly.  See the description  of  -f  above  for  details.
       This  variable  may  also be necessary in order for times-
       tamps on extracted files to be set correctly.  Under  Win-
       dows  95/NT unzip should know the correct timezone even if
       TZ is unset, assuming the timezone is correctly set in the
       Control Panel.

DECRYPTION
       Encrypted  archives  are fully supported by Info-ZIP soft-
       ware,  but  due  to  United  States  export  restrictions,
       de-/encryption  support might be disabled in your compiled
       binary.  However, since spring 2000,  US  export  restric-
       tions  have been liberated, and our source archives do now
       include full crypt code.  In case you need binary  distri-
       butions with crypt support enabled, see the file ``WHERE''
       in any Info-ZIP source or binary  distribution  for  loca-
       tions both inside and outside the US.

       Some  compiled  versions  of unzip may not support decryp-
       tion.  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.

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UNZIP(1L)                                               UNZIP(1L)

       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  nor-
       mally; 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  incor-
       rect  password is given but it passes the header test any-
       way, either an incorrect CRC will  be  generated  for  the
       extracted  data or else unzip will fail during the extrac-
       tion 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 posi-
       tives'' 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 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 encod-
       ings other than Latin-1 are not supported.

EXAMPLES
       To use unzip to extract all members of  the  archive  let-
       ters.zip  into  the  current  directory and subdirectories
       below it, creating any subdirectories as necessary:

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UNZIP(1L)                                               UNZIP(1L)

           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 indi-
       cating whether the archive is OK or not:

           unzip -tq letters

       To test all zipfiles in the  current  directory,  printing
       only the summaries:

           unzip -tq \*.zip

       (The backslash before the asterisk is only required if the
       shell expands wildcards, as in Unix; double  quotes  could
       have   been  used  instead,  as  in  the  source  examples
       below.)  To extract to standard output all members of let-
       ters.zip  whose  names end in .tex, auto-converting to the
       local end-of-line convention and piping  the  output  into
       more(1):

           unzip -ca letters \*.tex | more

       To  extract  the binary file paper1.dvi to standard output
       and pipe it to a printing program:

           unzip -p articles paper1.dvi | dvips

       To extract all FORTRAN and C source files--*.f, *.c,  *.h,
       and Makefile--into the /tmp directory:

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

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

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UNZIP(1L)                                               UNZIP(1L)

       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 cur-
       rent  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