ZIPINFO(1L)
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 specifica-
tion 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).
(Be sure to quote any character that might other-
wise 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; just specify the .exe suf-
fix (if any) explicitly.
[file(s)]
An optional list of archive members to be pro-
cessed. 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 head-
ers (-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 com-
pression 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 Unixmore(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 com-
pressed 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. Note that the total compressed (data)
size will never match the actual zipfile size,
since the latter includes all of the internal zip-
file headers in addition to the compressed data.
-T print the file dates and times in a sortable deci-
mal format (yymmdd.hhmmss). The default date for-
mat is a more standard, human-readable version with
abbreviated month names (see examples below).
-z include the archive comment (if any) in the list-
ing.
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. Interpreta-
tion 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, shrink-
ing, 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 lev-
els of deflating (superfast, fast, normal, maximum com-
pression). 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
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(1L)
and unzip.
In addition to individual file information, a default zip-
file 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 sec-
tion 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 for-
mat, whereas zipinfo always reports the 32-bit storage.)
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 over-
ride 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 indi-
vidual 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:
ZIPINFO=-l; export ZIPINFO Unix Bourne shell
setenv ZIPINFO -l Unix C shell
set ZIPINFO=-l OS/2 or MS-DOS
define ZIPINFO_OPTS "-l" VMS (quotes for lowercase)
If, in addition, the user dislikes the trailer line, zip-
info'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 exam-
ple. 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 ZIP-
INFO_OPTS for VMS (where the symbol used to install zip-
info as a foreign command would otherwise be confused with
the environment variable), and ZIPINFO for all other oper-
ating systems. For compatibility with zip(1L), ZIPINFOOPT
is also accepted (don't ask). If both ZIPINFO and ZIPIN-
FOOPT 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 con-
tents 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 glob-
bing 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 foot-
ers 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 list-
ing. 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 sum-
marized 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 tail(1) as well,
in this example):
zipinfo -T storage | sort -n +6 | tail -15
The -n option to sort(1) tells it to sort numerically
rather than in ASCII order, and the +6 option tells it to
sort on the sixth field after the first one (i.e., the
seventh field). This assumes the default short-listing
format; if -m or -l is used, the proper sort(1) option
would be +7. The tail(1) command filters out all but the
last 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 sys-
tems, 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(1L) unzip(1L) unzipsfx(1L) zip(1L) zip-
cloak(1L) zipnote(1L) zipsplit(1L)
URL
The Info-ZIP home page is currently at
http://www.cdrom.com/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.