zipinfo(1)
NAME
zipinfo - list detailed information about a ZIP archive
SYNOPSIS
zipinfo [-12smlvhMtTz] file[.zip] [file(s) ...] [-x xfile(s) ...]
unzip -Z [-12smlvhMtTz] file[.zip] [file(s) ...] [-x xfile(s) ...]
DESCRIPTION
zipinfo lists technical information about files in a ZIP archive, most
commonly found on MS-DOS systems. Such information includes file
access permissions, encryption status, type of compression, version and
operating system or file system of compressing program, and the like.
The default behavior (with no options) is to list single-line entries
for each file in the archive, with header and trailer lines providing
summary information for the entire archive. The format is a cross
between Unix ``ls -l'' and ``unzip -v'' output. See DETAILED
DESCRIPTION below. Note that zipinfo is the same program as unzip
(under Unix, a link to it); on some systems, however, zipinfo support
may have been omitted when unzip was compiled.
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 Unix egrep(1) (regular) expressions and may contain:
* matches a sequence of 0 or more characters
? matches exactly 1 character
[...] matches any single character found inside the brackets;
ranges are specified by a beginning character, a hyphen,
and an ending character. If an exclamation point or a
caret (`!' or `^') follows the left bracket, then the
range of characters within the brackets is complemented
(that is, anything except the characters inside the
brackets is considered a match). To specify a verbatim
left bracket, the three-character sequence ``[[]'' has to
be used.
(Be sure to quote any character that might otherwise be
interpreted or modified by the operating system, particularly
under Unix and VMS.) If no matches are found, the specification
is assumed to be a literal filename; and if that also fails, the
suffix .zip is appended. Note that self-extracting ZIP files
are supported, as with any other ZIP archive; just specify the
.exe suffix (if any) explicitly.
[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.) Regular expressions
(wildcards) may be used to match multiple members; see above.
Again, be sure to quote expressions that would otherwise be
expanded or modified by the operating system.
[-x xfile(s)]
An optional list of archive members to be excluded from
processing.
OPTIONS
-1 list filenames only, one per line. This option excludes all
others; headers, trailers and zipfile comments are never
printed. It is intended for use in Unix shell scripts.
-2 list filenames only, one per line, but allow headers (-h),
trailers (-t) and zipfile comments (-z), as well. This option
may be useful in cases where the stored filenames are
particularly long.
-s list zipfile info in short Unix ``ls -l'' format. This is the
default behavior; see below.
-m list zipfile info in medium Unix ``ls -l'' format. Identical to
the -s output, except that the compression factor, expressed as
a percentage, is also listed.
-l list zipfile info in long Unix ``ls -l'' format. As with -m
except that the compressed size (in bytes) is printed instead of
the compression ratio.
-v list zipfile information in verbose, multi-page format.
-h list header line. The archive name, actual size (in bytes) and
total number of files is printed.
-M pipe all output through an internal pager similar to the Unix
more(1) command. At the end of a screenful of output, zipinfo
pauses with a ``--More--'' prompt; the next screenful may be
viewed by pressing the Enter (Return) key or the space bar.
zipinfo 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, zipinfo doesn't
notice if long lines wrap at the edge of the screen, effectively
resulting in the printing of two or more lines and the
likelihood that some text will scroll off the top of the screen
before being viewed. On some systems the number of available
lines on the screen is not detected, in which case zipinfo
assumes the height is 24 lines.
-t list totals for files listed or for all files. The number of
files listed, their uncompressed and compressed total sizes ,
and their overall compression factor is printed; or, if only the
totals line is being printed, the values for the entire archive
are given. The compressed total size does not include the 12
additional header bytes of each encrypted entry. Note that the
total compressed (data) size will never match the actual zipfile
size, since the latter includes all of the internal zipfile
headers in addition to the compressed data.
-T print the file dates and times in a sortable decimal format
(yymmdd.hhmmss). The default date format is a more standard,
human-readable version with abbreviated month names (see
examples below).
-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''. This option is mainly provided for debugging
purpose when the fairly new UTF-8 support is suspected to mangle
up extracted filenames.
The option -UU allows to entirely disable the recognition of
UTF-8 encoded filenames. The handling of filename codings
within unzip falls back to the behaviour of previous versions.
-z include the archive comment (if any) in the listing.
DETAILED DESCRIPTION
zipinfo has a number of modes, and its behavior can be rather difficult
to fathom if one isn't familiar with Unix ls(1) (or even if one is).
The default behavior is to list files in the following format:
-rw-rws--- 1.9 unx 2802 t- defX 11-Aug-91 13:48 perms.2660
The last three fields are the modification date and time of the file,
and its name. The case of the filename is respected; thus files that
come from MS-DOS PKZIP are always capitalized. If the file was zipped
with a stored directory name, that is also displayed as part of the
filename.
The second and third fields indicate that the file was zipped under
Unix with version 1.9 of zip. Since it comes from Unix, the file
permissions at the beginning of the line are printed in Unix format.
The uncompressed file-size (2802 in this example) is the fourth field.
The fifth field consists of two characters, either of which may take on
several values. The first character may be either `t' or `b',
indicating that zip believes the file to be text or binary,
respectively; but if the file is encrypted, zipinfo notes this fact by
capitalizing the character (`T' or `B'). The second character may also
take on four values, depending on whether there is an extended local
header and/or an ``extra field'' associated with the file (fully
explained in PKWare's APPNOTE.TXT, but basically analogous to pragmas
in ANSI C--i.e., they provide a standard way to include non-standard
information in the archive). If neither exists, the character will be
a hyphen (`-'); if there is an extended local header but no extra
field, `l'; if the reverse, `x'; and if both exist, `X'. Thus the file
in this example is (probably) a text file, is not encrypted, and has
neither an extra field nor an extended local header associated with it.
The example below, on the other hand, is an encrypted binary file with
an extra field:
RWD,R,R 0.9 vms 168 Bx shrk 9-Aug-91 19:15 perms.0644
Extra fields are used for various purposes (see discussion of the -v
option below) including the storage of VMS file attributes, which is
presumably the case here. Note that the file attributes are listed in
VMS format. Some other possibilities for the host operating system
(which is actually a misnomer--host file system is more correct)
include OS/2 or NT with High Performance File System (HPFS), MS-DOS,
OS/2 or NT with File Allocation Table (FAT) file system, and Macintosh.
These are denoted as follows:
-rw-a-- 1.0 hpf 5358 Tl i4:3 4-Dec-91 11:33 longfilename.hpfs
-r--ahs 1.1 fat 4096 b- i4:2 14-Jul-91 12:58 EA DATA. SF
--w------- 1.0 mac 17357 bx i8:2 4-May-92 04:02 unzip.macr
File attributes in the first two cases are indicated in a Unix-like
format, where the seven subfields indicate whether the file: (1) is a
directory, (2) is readable (always true), (3) is writable, (4) is
executable (guessed on the basis of the extension--.exe, .com, .bat,
.cmd and .btm files are assumed to be so), (5) has its archive bit set,
(6) is hidden, and (7) is a system file. Interpretation of Macintosh
file attributes is unreliable because some Macintosh archivers don't
store any attributes in the archive.
Finally, the sixth field indicates the compression method and possible
sub-method used. There are six methods known at present: storing (no
compression), reducing, shrinking, imploding, tokenizing (never
publicly released), and deflating. In addition, there are four levels
of reducing (1 through 4); four types of imploding (4K or 8K sliding
dictionary, and 2 or 3 Shannon-Fano trees); and four levels of
deflating (superfast, fast, normal, maximum compression). zipinfo
represents these methods and their sub-methods as follows: stor; re:1,
re:2, etc.; shrk; i4:2, i8:3, etc.; tokn; and defS, defF, defN, and
defX.
The medium and long listings are almost identical to the short format
except that they add information on the file's compression. The medium
format lists the file's compression factor as a percentage indicating
the amount of space that has been ``removed'':
-rw-rws--- 1.5 unx 2802 t- 81% defX 11-Aug-91 13:48 perms.2660
In this example, the file has been compressed by more than a factor of
five; the compressed data are only 19% of the original size. The long
format gives the compressed file's size in bytes, instead:
-rw-rws--- 1.5 unx 2802 t- 538 defX 11-Aug-91 13:48 perms.2660
In contrast to the unzip listings, the compressed size figures in this
listing format denote the complete size of compressed data, including
the 12 extra header bytes in case of encrypted entries.
Adding the -T option changes the file date and time to decimal format:
-rw-rws--- 1.5 unx 2802 t- 538 defX 910811.134804 perms.2660
Note that because of limitations in the MS-DOS format used to store
file times, the seconds field is always rounded to the nearest even
second. For Unix files this is expected to change in the next major
releases of zip(1) and unzip.
In addition to individual file information, a default zipfile listing
also includes header and trailer lines:
Archive: OS2.zip 5453 bytes 5 files
,,rw, 1.0 hpf 730 b- i4:3 26-Jun-92 23:40 Contents
,,rw, 1.0 hpf 3710 b- i4:3 26-Jun-92 23:33 makefile.os2
,,rw, 1.0 hpf 8753 b- i8:3 26-Jun-92 15:29 os2unzip.c
,,rw, 1.0 hpf 98 b- stor 21-Aug-91 15:34 unzip.def
,,rw, 1.0 hpf 95 b- stor 21-Aug-91 17:51 zipinfo.def
5 files, 13386 bytes uncompressed, 4951 bytes compressed: 63.0%
The header line gives the name of the archive, its total size, and the
total number of files; the trailer gives the number of files listed,
their total uncompressed size, and their total compressed size (not
including any of zip's internal overhead). If, however, one or more
file(s) are provided, the header and trailer lines are not listed.
This behavior is also similar to that of Unix's ``ls -l''; it may be
overridden by specifying the -h and -t options explicitly. In such a
case the listing format must also be specified explicitly, since -h or
-t (or both) in the absence of other options implies that ONLY the
header or trailer line (or both) is listed. See the EXAMPLES section
below for a semi-intelligible translation of this nonsense.
The verbose listing is mostly self-explanatory. It also lists file
comments and the zipfile comment, if any, and the type and number of
bytes in any stored extra fields. Currently known types of extra
fields include PKWARE's authentication (``AV'') info; OS/2 extended
attributes; VMS filesystem info, both PKWARE and Info-ZIP versions;
Macintosh resource forks; Acorn/Archimedes SparkFS info; and so on.
(Note that in the case of OS/2 extended attributes--perhaps the most
common use of zipfile extra fields--the size of the stored EAs as
reported by zipinfo may not match the number given by OS/2's dir
command: OS/2 always reports the number of bytes required in 16-bit
format, whereas zipinfo always reports the 32-bit storage.)
Again, the compressed size figures of the individual entries include
the 12 extra header bytes for encrypted entries. In contrast, the
archive total compressed size and the average compression ratio shown
in the summary bottom line are calculated without the extra 12 header
bytes of encrypted entries.
ENVIRONMENT OPTIONS
Modifying zipinfo's default behavior via options placed in an
environment variable can be a bit complicated to explain, due to
zipinfo's attempts to handle various defaults in an intuitive, yet
Unix-like, manner. (Try not to laugh.) Nevertheless, there is some
underlying logic. In brief, there are three ``priority levels'' of
options: the default options; environment options, which can override
or add to the defaults; and explicit options given by the user, which
can override or add to either of the above.
The default listing format, as noted above, corresponds roughly to the
"zipinfo -hst" command (except when individual zipfile members are
specified). A user who prefers the long-listing format (-l) can make
use of the zipinfo's environment variable to change this default:
Unix Bourne shell:
ZIPINFO=-l; export ZIPINFO
Unix C shell:
setenv ZIPINFO -l
OS/2 or MS-DOS:
set ZIPINFO=-l
VMS (quotes for lowercase):
define ZIPINFO_OPTS "-l"
If, in addition, the user dislikes the trailer line, zipinfo's concept
of ``negative options'' may be used to override the default inclusion
of the line. This is accomplished by preceding the undesired option
with one or more minuses: e.g., ``-l-t'' or ``--tl'', in this example.
The first hyphen is the regular switch character, but the one before
the `t' is a minus sign. The dual use of hyphens may seem a little
awkward, but it's reasonably intuitive nonetheless: simply ignore the
first hyphen and go from there. It is also consistent with the
behavior of the Unix command nice(1).
As suggested above, the default variable names are ZIPINFO_OPTS for VMS
(where the symbol used to install zipinfo as a foreign command would
otherwise be confused with the environment variable), and ZIPINFO for
all other operating systems. For compatibility with zip(1), ZIPINFOOPT
is also accepted (don't ask). If both ZIPINFO and ZIPINFOOPT are
defined, however, ZIPINFO 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.
EXAMPLES
To get a basic, short-format listing of the complete contents of a ZIP
archive storage.zip, with both header and totals lines, use only the
archive name as an argument to zipinfo:
zipinfo storage
To produce a basic, long-format listing (not verbose), including header
and totals lines, use -l:
zipinfo -l storage
To list the complete contents of the archive without header and totals
lines, either negate the -h and -t options or else specify the contents
explicitly:
zipinfo --h-t storage
zipinfo storage \*
(where the backslash is required only if the shell would otherwise
expand the `*' wildcard, as in Unix when globbing is turned on--double
quotes around the asterisk would have worked as well). To turn off the
totals line by default, use the environment variable (C shell is
assumed here):
setenv ZIPINFO --t
zipinfo storage
To get the full, short-format listing of the first example again, given
that the environment variable is set as in the previous example, it is
necessary to specify the -s option explicitly, since the -t option by
itself implies that ONLY the footer line is to be printed:
setenv ZIPINFO --t
zipinfo -t storage [only totals line]
zipinfo -st storage [full listing]
The -s option, like -m and -l, includes headers and footers by default,
unless otherwise specified. Since the environment variable specified
no footers and that has a higher precedence than the default behavior
of -s, an explicit -t option was necessary to produce the full listing.
Nothing was indicated about the header, however, so the -s option was
sufficient. Note that both the -h and -t options, when used by
themselves or with each other, override any default listing of member
files; only the header and/or footer are printed. This behavior is
useful when zipinfo is used with a wildcard zipfile specification; the
contents of all zipfiles are then summarized with a single command.
To list information on a single file within the archive, in medium
format, specify the filename explicitly:
zipinfo -m storage unshrink.c
The specification of any member file, as in this example, will override
the default header and totals lines; only the single line of
information about the requested file will be printed. This is
intuitively what one would expect when requesting information about a
single file. For multiple files, it is often useful to know the total
compressed and uncompressed size; in such cases -t may be specified
explicitly:
zipinfo -mt storage "*.[ch]" Mak\*
To get maximal information about the ZIP archive, use the verbose
option. It is usually wise to pipe the output into a filter such as
Unix more(1) if the operating system allows it:
zipinfo -v storage | more
Finally, to see the most recently modified files in the archive, use
the -T option in conjunction with an external sorting utility such as
Unix sort(1) (and sed(1) as well, in this example):
zipinfo -T storage | sort -nr -k 7 | sed 15q
The -nr option to sort(1) tells it to sort numerically in reverse order
rather than in textual order, and the -k 7 option tells it to sort on
the seventh field. This assumes the default short-listing format; if
-m or -l is used, the proper sort(1) option would be -k 8. Older
versions of sort(1) do not support the -k option, but you can use the
traditional + option instead, e.g., +6 instead of -k 7. The sed(1)
command filters out all but the first 15 lines of the listing. Future
releases of zipinfo may incorporate date/time and filename sorting as
built-in options.
TIPS
The author finds it convenient to define an alias ii for zipinfo on
systems that allow aliases (or, on other systems, copy/rename the
executable, create a link or create a command file with the name ii).
The ii usage parallels the common ll alias for long listings in Unix,
and the similarity between the outputs of the two commands was
intentional.
BUGS
As with unzip, zipinfo's -M (``more'') option is overly simplistic in
its handling of screen output; as noted above, it fails to detect the
wrapping of long lines and may thereby cause lines at the top of the
screen to be scrolled off before being read. zipinfo should detect and
treat each occurrence of line-wrap as one additional line printed.
This requires knowledge of the screen's width as well as its height.
In addition, zipinfo should detect the true screen geometry on all
systems.
zipinfo's listing-format behavior is unnecessarily complex and should
be simplified. (This is not to say that it will be.)
SEE ALSO
ls(1), funzip(1), unzip(1), unzipsfx(1), zip(1), zipcloak(1),
zipnote(1), zipsplit(1)
URL
The Info-ZIP home page is currently at
http://www.info-zip.org/pub/infozip/
or
ftp://ftp.info-zip.org/pub/infozip/ .
AUTHOR
Greg ``Cave Newt'' Roelofs. ZipInfo contains pattern-matching code by
Mark Adler and fixes/improvements by many others. Please refer to the
CONTRIBS file in the UnZip source distribution for a more complete
list.
Free and Open Source Software