unzip

NAME

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

SYNOPSIS

unzip [-Z] [-cflptuvz[ajnoqsUV]] file[.zip]
	[file ...] [-x xfile ...] [-d exdir]

DESCRIPTION

The unzip(1) 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(1), creates ZIP archives; both programs are compatible with PKWARE's PKZIP and PKUNZIP for MS-DOS.

The main operands are the archive file, the members, a list of members to be excluded from processing, and a directory in which the extraction should take place. Only the archive is required.

file[.zip]
The path of one or more ZIP archives. 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 file name can be a wildcard; the path itself cannot. Wildcard expressions are similar to egrep(1) (regular) expressions and can contain:
*
Matches a sequence of 0 or more characters.
?
Matches exactly one 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, 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 otherwise be interpreted or modified by the operating system or shells.) If no matches are found, the specification is assumed to be a literal file name; if that also fails, the suffix .zip is appended. Note that self-extracting ZIP files are supported; just specify the .exe suffix (if any) explicitly.

file
The file, if specified, is the archive members to be processed. You can match multiple members with regular expressions (wildcards) as above. Again, be sure to quote expressions that would otherwise be expanded
-d exdir
Extract files in the directory exdir. By default, all files and subdirectories are recreated in the current directory; 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 immediately after the zipfile specification, or between the file and the -x option.
-x xfile
Exclude the archive members xfile from processing. Because wildcard characters match directory separators ('/'), this option can be used to exclude any files that are in subdirectories. For example, "unzip cat *.[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.

Besides those operands, unzip(1) also accepts the following options, which specify actions:

-c
Extract files to stdout/screen ("CRT"). This option is similar 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.
-f
Freshen existing files; that is, extract only those files that already exist on disk and which are newer than the disk copies. By default unzip(1) queries before overwriting, but the -o option can be used to suppress the queries.
-l
List archive files (short format). The name, uncompressed file size, and modification date and time of each specified file is printed, along with totals for all files specified. If a file was archived from a single-case file system (for example, the MS-DOS file allocation table (FAT) file system) and the -U option was not given, the file name is converted to lowercase and is prefixed with a caret (^). In addition, the archive comment and individual file comments (if any) are displayed.
-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 cyclic redundancy check (CRC), an enhanced checksum, of the expanded file with the original file's stored CRC value.
-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; in addition, it extracts those files that do not already exist on disk.
-v
List archive files (verbose format). In addition to the information given by the -l option, the compression method, compressed size, compression ratio and 32-bit CRC is listed.
-z
Display only the archive comment.
-Z
zipinfo(1) mode. If the first option on the command line is -Z, the remaining options are taken to be zipinfo(1) options. See the appropriate manual page for a description of these options.

Modifiers

The following options modify the behavior of one or more actions:

-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(1) as text files (those with the 't' rather than 'b'label in zipinfo(1) listings ) to be automatically extracted as such, converting line endings, end-of-file characters, and the character set itself as necessary. For example, Interix files use line feeds (LFs) for end-of-line (EOL) and have no end-of-file (EOF) marker; Macintosh computers use carriage returns (CRs) for EOLs; and most PC-based operating systems use CR+LF for EOLs and CTRL+Z for EOF. In addition, IBM mainframes and the Michigan Terminal System use EBCDIC rather than the more common ASCII character set, and Windows supports Unicode.) Note that the zip(1) utility's identification of text files is by no means perfect; some "text" files can actually be binary and vice versa. The unzip(1) utility 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.
-j
Junk paths. The archive's directory structure is not recreated; all files are deposited in the extraction directory (by default, the current one).
-n
Never overwrite existing files. If a file already exists, skip the extraction of that file without prompting. By default, unzip(1) queries before extracting any file that already exists; the user can 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.
-o
Overwrite existing files without prompting. This is a dangerous option, so use it with care. (It is often used with -f, however.)
-q
Perform operations quietly (-qq=even quieter). Ordinarily, unzip(1) prints the names of the files it is extracting or testing, the extraction methods, any file or zipfile comments that might be stored in the archive, and possibly a summary when finished with each archive. The -q and -qq options suppress the printing of some or all of these messages.
-s
[OS/2, Windows, MS-DOS] Convert spaces in file names to underscores. By default, unzip(1) extracts file names with spaces intact (for example, "EA DATA. SF"). This can be awkward, however, because MS-DOS in particular does not gracefully support spaces in file names. Conversion of spaces to underscores can eliminate this awkwardness in some cases.
-U
Leave file names uppercase if created under MS-DOS, VMS, and so on. Depending on the archiver, files archived under single-case file systems can be stored as all-uppercase names; this can be awkward when extracting to a case-preserving file system such as OS/2 HPFS or a case-sensitive one, such as under Interix. By default unzip(1) converts such file names to lowercase; this option causes all file names to be extracted exactly as they are stored (except in the cases of truncation, conversion of unsupported characters, and the like).
-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 file names to particularly short lengths, the version numbers can be truncated or stripped regardless of this option.)
-X
[VMS] Restore owner/protection info (might require system privileges). Ordinary file attributes are always restored, but this option also allows unique identifier codes(UICs) to be restored.
-$
[MS-DOS, OS/2, Windows, Amiga] Restore the volume label if the extraction medium is removable (as, for example, in the case of a a diskette). Doubling the option (-$$) allows fixed media (hard disks) to be labelled as well. By default, volume labels are ignored.

ENVIRONMENT OPTIONS

The unzip(1)utility's default behavior can be modified by using options placed in an environment variable. This can be done with any option, but it is probably most useful with the -q, -a, -o, or -n modifiers: make unzip(1) quieter by default, make it auto-convert text files, or make it always overwrite or never overwrite files as it extracts them. For example, to make unzip(1) act as quietly as possible, only reporting errors, one would use one of the following commands:

UNZIP=-qq; export UNZIP  Bourne shell
setenv UNZIP -qq		 BSD C shell

Environment options are 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, 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 can be used:

unzip -t--q zipfile
unzip ---qt zipfile

(the two are equivalent). This might seem awkward or confusing, but it is reasonably intuitive: just ignore the first hyphen and go from there.

EXAMPLES

To use unzip(1) to extract all members of the archive letters.zip into the current directory and subdirectories below it, creating any subdirectories as necessary, use:

unzip letters"

To extract all members of letters.zip into the current directory only, use:

unzip -j letters

To test letters.zip, printing only a summary message indicating whether the archive is OK or not, use:

unzip -tq letters

To extract to standard output 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), use:

unzip -ca letters \*.tex | more"

(The backslash before the asterisk is required when the shell expands wildcards, as with Interix; double quotes could have been used instead, as in the source example provided later in this topic.) To extract the binary file paper1.dvi to standard output and pipe it to a printing program, use:

unzip -p articles paper1.dvi | dvips

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

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

(the double quotes are necessary to have the shell treat the enclosed characters as literals). To extract only newer versions of the files already in the current directory, without querying, use the following (NOTE: Be careful when unzipping in one time zone a zip file created in another. ZIP archives to date contain no time-zone information, and a "newer" file from an eastern time zone can, 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 example), use:

unzip -uo sources"

In the last five examples, assume that UNZIP or UNZIP_OPTS is set to -q. To do a singly quiet listing:

unzip -l file

To do a doubly quiet listing:

unzip -ql file

To do a standard listing, use:

unzip --ql file

or

unzip -l-q file

or

unzip -l--q file	(extra minuses don't hurt)

TIPS

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 can then simply type "tt zipfile" to test an archive something that is worth making a habit of doing. With luck unzip(1) will report "No errors detected in zipfile.zip,".

BUGS

Under DEC Ultrix, unzip(1) will sometimes fail on long zipfiles (bad Cyclical Redundancy Checking (CRC), not always reproducible). This is apparently due either to a hardware bug (cache memory) or an operating system bug (improper handling of page faults?).

Dates and times of stored directories are not restored.

VERSIONS

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, maint.)
v5.0 21 Aug 92
Info-ZIP (zip-bugs subgroup; GRR, maint.)
v5.1 7 Feb 94
Info-ZIP (zip-bugs subgroup; GRR, maint.)

SEE ALSO

zip(1)