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Annotated edit history of unzip(1) version 2, including all changes. View license author blame.

Rev	Author	#	Line
1	perry	1	UNZIP
		2	!!!UNZIP
		3	NAME
		4	SYNOPSIS
		5	DESCRIPTION
		6	ARGUMENTS
		7	OPTIONS
		8	MODIFIERS
		9	ENVIRONMENT OPTIONS
		10	DECRYPTION
		11	EXAMPLES
		12	TIPS
		13	DIAGNOSTICS
		14	BUGS
		15	SEE ALSO
		16	URL
		17	AUTHORS
		18	VERSIONS
		19	----
		20	!!NAME
		21
		22
		23	unzip - list, test and extract compressed files in a ZIP archive
		24	!!SYNOPSIS
		25
		26
		27	__unzip__ [[__-Z__]
		28	[[__-cflptuvz__[[__abjnoqsCLMVX$/:__]]
		29	''file''[[''.zip''] [[''file(s)'' ...] [[__-x__
		30	''xfile(s)'' ...] [[__-d__ ''exdir'']
		31	!!DESCRIPTION
		32
		33
		34	''unzip'' will list, test, or extract files from a ZIP
		35	archive, commonly found on MS-DOS systems. The default
		36	behavior (with no options) is to extract into the current
		37	directory (and subdirectories below it) all files from the
		38	specified ZIP archive. A companion program, ''zip''(1L),
		39	creates ZIP archives; both programs are compatible with
		40	archives created by PKWARE's ''PKZIP'' and ''PKUNZIP''
		41	for MS-DOS, but in many cases the program options or default
		42	behaviors differ.
		43	!!ARGUMENTS
		44
		45
		46	''file''[[''.zip'']
		47
		48
		49	Path of the ZIP archive(s). If the file specification is a
		50	wildcard, each matching file is processed in an order
		51	determined by the operating system (or file system). Only
		52	the filename can be a wildcard; the path itself cannot.
		53	Wildcard expressions are similar to those supported in
		54	commonly used Unix shells (''sh'', ''ksh'',
		55	''csh'') and may contain:
		56
		57
		58	*
		59
		60
		61	matches a sequence of 0 or more characters
		62
		63
		64	?
		65
		66
		67	matches exactly 1 character
		68
		69
		70	[[...]
		71
		72
		73	matches any single character found inside the brackets;
		74	ranges are specified by a beginning character, a hyphen, and
		75	an ending character. If an exclamation point or a caret (`!'
		76	or `^') follows the left bracket, then the range of
		77	characters within the brackets is complemented (that is,
		78	anything ''except'' the characters inside the brackets is
		79	considered a match).
		80
		81
		82	(Be sure to quote any character that might otherwise be
		83	interpreted or modified by the operating system,
		84	particularly under Unix and VMS.) If no matches are found,
		85	the specification is assumed to be a literal filename; and
		86	if that also fails, the suffix .zip is appended.
		87	Note that self-extracting ZIP files are supported, as with
		88	any other ZIP archive; just specify the .exe suffix
		89	(if any) explicitly.
		90
		91
		92	[[''file(s)'']
		93
		94
		95	An optional list of archive members to be processed,
		96	separated by spaces. (VMS versions compiled with VMSCLI
		97	defined must delimit files with commas instead. See
		98	__-v__ in __OPTIONS__ below.) Regular expressions
		99	(wildcards) may be used to match multiple members; see
		100	above. Again, be sure to quote expressions that would
		101	otherwise be expanded or modified by the operating
		102	system.
		103
		104
		105	[[__-x__ ''xfile(s)'']
		106
		107
		108	An optional list of archive members to be excluded from
		109	processing. Since wildcard characters match directory
		110	separators (`/'), this option may be used to exclude any
		111	files that are in subdirectories. For example, ``unzip
		112	foo *.[[ch] -x */*'' would extract all C source files in
		113	the main directory, but none in any subdirectories. Without
		114	the __-x__ option, all C source files in all directories
		115	within the zipfile would be extracted.
		116
		117
		118	[[__-d__ ''exdir'']
		119
		120
		121	An optional directory to which to extract files. By default,
		122	all files and subdirectories are recreated in the current
		123	directory; the __-d__ option allows extraction in an
		124	arbitrary directory (always assuming one has permission to
		125	write to the directory). This option need not appear at the
		126	end of the command line; it is also accepted before the
		127	zipfile specification (with the normal options), immediately
		128	after the zipfile specification, or between the
		129	''file(s)'' and the __-x__ option. The option and
		130	directory may be concatenated without any white space
		131	between them, but note that this may cause normal shell
		132	behavior to be suppressed. In particular, ``-d ~''
		133	(tilde) is expanded by Unix C shells into the name of the
		134	user's home directory, but ``-d~'' is treated as a
		135	literal subdirectory ``__~__'' of the current
		136	directory.
		137	!!OPTIONS
		138
		139
		140	Note that, in order to support obsolescent hardware,
		141	''unzip'''s usage screen is limited to 22 or 23 lines and
		142	should therefore be considered only a reminder of the basic
		143	''unzip'' syntax rather than an exhaustive list of all
		144	possible flags. The exhaustive list follows:
		145
		146
		147	__-Z__
		148
		149
		150	''zipinfo''(1L) mode. If the first option on the command
		151	line is __-Z__, the remaining options are taken to be
		152	''zipinfo''(1L) options. See the appropriate manual page
		153	for a description of these options.
		154
		155
		156	__-A__
		157
		158
		159	[[OS/2, Unix DLL] print extended help for the DLL's
		160	programming interface (API).
		161
		162
		163	__-c__
		164
		165
		166	extract files to stdout/screen (``CRT''). This option is
		167	similar to the __-p__ option except that the name of each
		168	file is printed as it is extracted, the __-a__ option is
		169	allowed, and ASCII-EBCDIC conversion is automatically
		170	performed if appropriate. This option is not listed in the
		171	''unzip'' usage screen.
		172
		173
		174	__-f__
		175
		176
		177	freshen existing files, i.e., extract only those files that
		178	already exist on disk and that are newer than the disk
		179	copies. By default ''unzip'' queries before overwriting,
		180	but the __-o__ option may be used to suppress the
		181	queries. Note that under many operating systems, the TZ
		182	(timezone) environment variable must be set correctly in
		183	order for __-f__ and __-u__ to work properly (under
		184	Unix the variable is usually set automatically). The reasons
		185	for this are somewhat subtle but have to do with the
		186	differences between DOS-format file times (always local
		187	time) and Unix-format times (always in GMT/UTC) and the
		188	necessity to compare the two. A typical TZ value is
		189	``PST8PDT'' (US Pacific time with automatic adjustment for
		190	Daylight Savings Time or ``summer time'').
		191
		192
		193	__-l__
		194
		195
		196	list archive files (short format). The names, uncompressed
		197	file sizes and modification dates and times of the specified
		198	files are printed, along with totals for all files
2	perry	199	specified. If !UnZip was compiled with OS2_EAS defined, the
1	perry	200	__-l__ option also lists columns for the sizes of stored
		201	OS/2 extended attributes (EAs) and OS/2 access control lists
		202	(ACLs). In addition, the zipfile comment and individual file
		203	comments (if any) are displayed. If a file was archived from
		204	a single-case file system (for example, the old MS-DOS FAT
		205	file system) and the __-L__ option was given, the
		206	filename is converted to lowercase and is prefixed with a
		207	caret (^).
		208
		209
		210	__-p__
		211
		212
		213	extract files to pipe (stdout). Nothing but the file data is
		214	sent to stdout, and the files are always extracted in binary
		215	format, just as they are stored (no
		216	conversions).
		217
		218
		219	__-t__
		220
		221
		222	test archive files. This option extracts each specified file
		223	in memory and compares the CRC (cyclic redundancy check, an
		224	enhanced checksum) of the expanded file with the original
		225	file's stored CRC value.
		226
		227
		228	__-T__
		229
		230
		231	[[most OSes] set the timestamp on the archive(s) to that of
		232	the newest file in each one. This corresponds to
		233	''zip'''s __-go__ option except that it can be used on
		234	wildcard zipfiles (e.g., ``unzip -T *.zip'') and is
		235	much faster.
		236
		237
		238	__-u__
		239
		240
		241	update existing files and create new ones if needed. This
		242	option performs the same function as the __-f__ option,
		243	extracting (with query) files that are newer than those with
		244	the same name on disk, and in addition it extracts those
		245	files that do not already exist on disk. See __-f__ above
		246	for information on setting the timezone
		247	properly.
		248
		249
		250	__-v__
		251
		252
		253	be verbose or print diagnostic version info. This option has
		254	evolved and now behaves as both an option and a modifier. As
		255	an option it has two purposes: when a zipfile is specified
		256	with no other options, __-v__ lists archive files
		257	verbosely, adding to the basic __-l__ info the
		258	compression method, compressed size, compression ratio and
		259	32-bit CRC. When no zipfile is specified (that is, the
		260	complete command is simply ``unzip -v''), a
		261	diagnostic screen is printed. In addition to the normal
		262	header with release date and version, ''unzip'' lists the
		263	home Info-ZIP ftp site and where to find a list of other ftp
		264	and non-ftp sites; the target operating system for which it
		265	was compiled, as well as (possibly) the hardware on which it
		266	was compiled, the compiler and version used, and the
		267	compilation date; any special compilation options that might
		268	affect the program's operation (see also __DECRYPTION__
		269	below); and any options stored in environment variables that
		270	might do the same (see __ENVIRONMENT OPTIONS__ below). As
		271	a modifier it works in conjunction with other options (e.g.,
		272	__-t__) to produce more verbose or debugging output; this
		273	is not yet fully implemented but will be in future
		274	releases.
		275
		276
		277	__-z__
		278
		279
		280	display only the archive comment.
		281	!!MODIFIERS
		282
		283
		284	__-a__
		285
		286
		287	convert text files. Ordinarily all files are extracted
		288	exactly as they are stored (as ``binary'' files). The
		289	__-a__ option causes files identified by ''zip'' as
		290	text files (those with the `t' label in ''zipinfo''
		291	listings, rather than `b') to be automatically extracted as
		292	such, converting line endings, end-of-file characters and
		293	the character set itself as necessary. (For example, Unix
		294	files use line feeds (LFs) for end-of-line (EOL) and have no
		295	end-of-file (EOF) marker; Macintoshes use carriage returns
		296	(CRs) for EOLs; and most PC operating systems use CR+LF for
		297	EOLs and control-Z for EOF. In addition, IBM mainframes and
		298	the Michigan Terminal System use EBCDIC rather than the more
		299	common ASCII character set, and NT supports Unicode.) Note
		300	that ''zip'''s identification of text files is by no
		301	means perfect; some ``text'' files may actually be binary
		302	and vice versa. ''unzip'' therefore prints
		303	``[[text]'' or ``[[binary]'' as a visual
		304	check for each file it extracts when using the __-a__
		305	option. The __-aa__ option forces all files to be
		306	extracted as text, regardless of the supposed file
		307	type.
		308
		309
		310	__-b__
		311
		312
		313	[[general] treat all files as binary (no text conversions).
		314	This is a shortcut for __---a__.
		315
		316
		317	__-b__
		318
		319
		320	[[Tandem] force the creation files with filecode type 180
		321	('C') when extracting Zip entries marked as
		322	-a__ is enabled by
		323	default, see above).
		324
		325
		326	__-b__
		327
		328
		329	[[VMS] auto-convert binary files (see __-a__ above) to
		330	fixed-length, 512-byte record format. Doubling the option
		331	(__-bb__) forces all files to be extracted in this
		332	format. When extracting to standard output (__-c__ or
		333	__-p__ option in effect), the default conversion of text
		334	record delimiters is disabled for binary (__-b__) resp.
		335	all (__-bb__) files.
		336
		337
		338	__-B__
		339
		340
		341	[[Unix only, and only if compiled with UNIXBACKUP defined]
		342	save a backup copy of each overwritten file with a tilde
		343	appended (e.g., the old copy of ``foo'' is renamed
		344	to ``foo~''). This is similar to the default
		345	behavior of emacs(1) in many locations.
		346
		347
		348	__-C__
		349
		350
		351	match filenames case-insensitively. ''unzip'''s
		352	philosophy is ``you get what you ask for'' (this is also
		353	responsible for the __-L__/__-U__ change; see the
		354	relevant options below). Because some file systems are fully
		355	case-sensitive (notably those under the Unix operating
		356	system) and because both ZIP archives and ''unzip''
		357	itself are portable across platforms, ''unzip'''s default
		358	behavior is to match both wildcard and literal filenames
		359	case-sensitively. That is, specifying ``makefile''
		360	on the command line will ''only'' match ``makefile'' in
		361	the archive, not ``Makefile'' or ``MAKEFILE'' (and similarly
		362	for wildcard specifications). Since this does not correspond
		363	to the behavior of many other operating/file systems (for
		364	example, OS/2 HPFS, which preserves mixed case but is not
		365	sensitive to it), the __-C__ option may be used to force
		366	all filename matches to be case-insensitive. In the example
		367	above, all three files would then match
		368	``makefile'' (or ``make*'', or similar).
		369	The __-C__ option affects files in both the normal file
		370	list and the excluded-file list (xlist).
		371
		372
		373	__-E__
		374
		375
		376	[[MacOS only] display contents of MacOS extra field during
		377	restore operation.
		378
		379
		380	__-F__
		381
		382
		383	[[Acorn only] suppress removal of NFS filetype extension from
		384	stored filenames.
		385
		386
		387	__-F__
		388
		389
		390	[[non-Acorn systems supporting long filenames with embedded
		391	commas, and only if compiled with ACORN_FTYPE_NFS defined]
		392	translate filetype information from ACORN RISC OS extra
		393	field blocks into a NFS filetype extension and append it to
		394	the names of the extracted files. (When the stored filename
		395	appears to already have an appended NFS filetype extension,
		396	it is replaced by the info from the extra
		397	field.)
		398
		399
		400	__-i__
		401
		402
		403	[[MacOS only] ignore filenames stored in MacOS extra fields.
		404	Instead, the most compatible filename stored in the generic
		405	part of the entry's header is used.
		406
		407
		408	__-j__
		409
		410
		411	junk paths. The archive's directory structure is not
		412	recreated; all files are deposited in the extraction
		413	directory (by default, the current one).
		414
		415
		416	__-J__
		417
		418
		419	[[BeOS only] junk file attributes. The file's BeOS file
		420	attributes are not restored, just the file's
		421	data.
		422
		423
		424	__-J__
		425
		426
		427	[[MacOS only] ignore MacOS extra fields. All Macintosh
		428	specific info is skipped. Data-fork and resource-fork are
		429	restored as separate files.
		430
		431
		432	__-L__
		433
		434
		435	convert to lowercase any filename originating on an
		436	uppercase-only operating system or file system. (This was
		437	''unzip'''s default behavior in releases prior to 5.11;
		438	the new default behavior is identical to the old behavior
		439	with the __-U__ option, which is now obsolete and will be
		440	removed in a future release.) Depending on the archiver,
		441	files archived under single-case file systems (VMS, old
		442	MS-DOS FAT, etc.) may be stored as all-uppercase names; this
		443	can be ugly or inconvenient when extracting to a
		444	case-preserving file system such as OS/2 HPFS or a
		445	case-sensitive one such as under Unix. By default
		446	''unzip'' lists and extracts such filenames exactly as
		447	they're stored (excepting truncation, conversion of
		448	unsupported characters, etc.); this option causes the names
		449	of all files from certain systems to be converted to
		450	lowercase. The __-LL__ option forces conversion of every
		451	filename to lowercase, regardless of the originating file
		452	system.
		453
		454
		455	__-M__
		456
		457
		458	pipe all output through an internal pager similar to the
		459	Unix more(1) command. At the end of a screenful of
		460	output, ''unzip'' pauses with a ``--More--'' prompt; the
		461	next screenful may be viewed by pressing the Enter (Return)
		462	key or the space bar. ''unzip'' can be terminated by
		463	pressing the ``q'' key and, on some systems, the
		464	Enter/Return key. Unlike Unix more(1), there is no
		465	forward-searching or editing capability. Also, ''unzip''
		466	doesn't notice if long lines wrap at the edge of the screen,
		467	effectively resulting in the printing of two or more lines
		468	and the likelihood that some text will scroll off the top of
		469	the screen before being viewed. On some systems the number
		470	of available lines on the screen is not detected, in which
		471	case ''unzip'' assumes the height is 24
		472	lines.
		473
		474
		475	__-n__
		476
		477
		478	never overwrite existing files. If a file already exists,
		479	skip the extraction of that file without prompting. By
		480	default ''unzip'' queries before extracting any file that
		481	already exists; the user may choose to overwrite only the
		482	current file, overwrite all files, skip extraction of the
		483	current file, skip extraction of all existing files, or
		484	rename the current file.
		485
		486
		487	__-N__
		488
		489
		490	[[Amiga] extract file comments as Amiga filenotes. File
		491	comments are created with the -c option of ''zip''(1L),
		492	or with the -N option of the Amiga port of ''zip''(1L),
		493	which stores filenotes as comments.
		494
		495
		496	__-o__
		497
		498
		499	overwrite existing files without prompting. This is a
		500	dangerous option, so use it with care. (It is often used
		501	with __-f__, however, and is the only way to overwrite
		502	directory EAs under OS/2.)
		503
		504
		505	__-P__ ''password''
		506
		507
		508	use ''password'' to decrypt encrypted zipfile entries (if
		509	any). __THIS IS INSECURE!__ Many multi-user operating
		510	systems provide ways for any user to see the current command
		511	line of any other user; even on stand-alone systems there is
		512	always the threat of over-the-shoulder peeking. Storing the
		513	plaintext password as part of a command line in an automated
		514	script is even worse. Whenever possible, use the
		515	non-echoing, interactive prompt to enter passwords. (And
		516	where security is truly important, use strong encryption
		517	such as Pretty Good Privacy instead of the relatively weak
		518	encryption provided by standard zipfile
		519	utilities.)
		520
		521
		522	__-q__
		523
		524
		525	perform operations quietly (__-qq__ = even quieter).
		526	Ordinarily ''unzip'' prints the names of the files it's
		527	extracting or testing, the extraction methods, any file or
		528	zipfile comments that may be stored in the archive, and
		529	possibly a summary when finished with each archive. The
		530	__-q__[[__q__] options suppress the printing of some or
		531	all of these messages.
		532
		533
		534	__-s__
		535
		536
		537	[[OS/2, NT, MS-DOS] convert spaces in filenames to
		538	underscores. Since all PC operating systems allow spaces in
		539	filenames, ''unzip'' by default extracts filenames with
		540	spaces intact (e.g., ``EA DATA. SF''). This can be
		541	awkward, however, since MS-DOS in particular does not
		542	gracefully support spaces in filenames. Conversion of spaces
		543	to underscores can eliminate the awkwardness in some
		544	cases.
		545
		546
		547	__-U__
		548
		549
		550	(obsolete; to be removed in a future release) leave
		551	filenames uppercase if created under MS-DOS, VMS, etc. See
		552	__-L__ above.
		553
		554
		555	__-V__
		556
		557
		558	retain (VMS) file version numbers. VMS files can be stored
		559	with a version number, in the format file.ext;##.
		560	By default the ``;##'' version numbers are
		561	stripped, but this option allows them to be retained. (On
		562	file systems that limit filenames to particularly short
		563	lengths, the version numbers may be truncated or stripped
		564	regardless of this option.)
		565
		566
		567	__-X__
		568
		569
		570	[[VMS, Unix, OS/2, NT] restore owner/protection info (UICs)
		571	under VMS, or user and group info (UID/GID) under Unix, or
		572	access control lists (ACLs) under certain network-enabled
		573	versions of OS/2 (Warp Server with IBM LAN Server/Requester
		574	3.0 to 5.0; Warp Connect with IBM Peer 1.0), or security
		575	ACLs under Windows NT. In most cases this will require
		576	special system privileges, and doubling the option
		577	(__-XX__) under NT instructs ''unzip'' to use
		578	privileges for extraction; but under Unix, for example, a
		579	user who belongs to several groups can restore files owned
		580	by any of those groups, as long as the user IDs match his or
		581	her own. Note that ordinary file attributes are always
		582	restored--this option applies only to optional, extra
		583	ownership info available on some operating systems. [[NT's
		584	access control lists do not appear to be especially
		585	compatible with OS/2's, so no attempt is made at
		586	cross-platform portability of access privileges. It is not
		587	clear under what conditions this would ever be useful
		588	anyway.]
		589
		590
		591	__-$__
		592
		593
		594	[[MS-DOS, OS/2, NT] restore the volume label if the
		595	extraction medium is removable (e.g., a diskette). Doubling
		596	the option (__-$$__) allows fixed media (hard disks) to
		597	be labelled as well. By default, volume labels are
		598	ignored.
		599
		600
		601	__-/__ ''extensions''
		602
		603
		604	[[Acorn only] overrides the extension list supplied by
		605	Unzip$Ext environment variable. During extraction, filename
		606	extensions that match one of the items in this extension
		607	list are swapped in front of the base name of the extracted
		608	file.
		609
		610
		611	__-:__
		612
		613
		614	[[all but Acorn, VM/CMS, MVS, Tandem] allows to extract
		615	archive members into locations outside of the current ``
		616	extraction root folder''. For security reasons, ''unzip''
		617	normally removes ``parent dir'' path components (``../'')
		618	from the names of extracted file. This safety feature (new
		619	for version 5.50) prevents ''unzip'' from accidentally
		620	writing files to ``sensitive'' areas outside the active
		621	extraction folder tree head. The __-:__ option lets
		622	''unzip'' switch back to its previous, more liberal
		623	behaviour, to allow exact extraction of (older) archives
		624	that used ``../'' components to create multiple directory
		625	trees at the level of the current extraction
		626	folder.
		627	!!ENVIRONMENT OPTIONS
		628
		629
		630	''unzip'''s default behavior may be modified via options
		631	placed in an environment variable. This can be done with any
		632	option, but it is probably most useful with the __-a__,
		633	__-L__, __-C__, __-q__, __-o__, or __-n__
		634	modifiers: make ''unzip'' auto-convert text files by
		635	default, make it convert filenames from uppercase systems to
		636	lowercase, make it match names case-insensitively, make it
		637	quieter, or make it always overwrite or never overwrite
		638	files as it extracts them. For example, to make ''unzip''
		639	act as quietly as possible, only reporting errors, one would
		640	use one of the following commands:
		641
		642
		643	Unix Bourne shell:
		644
		645
		646	UNZIP=-qq; export UNZIP
		647
		648
		649	Unix C shell:
		650
		651
		652	setenv UNZIP -qq
		653
		654
		655	OS/2 or MS-DOS:
		656
		657
		658	set UNZIP=-qq
		659
		660
		661	VMS (quotes for ''lowercase''):
		662
		663
		664	define UNZIP_OPTS
		665
		666
		667	Environment options are, in effect, considered to be just
		668	like any other command-line options, except that they are
		669	effectively the first options on the command line. To
		670	override an environment option, one may use the ``minus
		671	operator'' to remove it. For instance, to override one of
		672	the quiet-flags in the example above, use the
		673	command
		674
		675
		676	unzip --q[[''other options''
		677
		678
		679	] zipfile
		680
		681
		682	The first hyphen is the normal switch character, and the
		683	second is a minus sign, acting on the q option. Thus the
		684	effect here is to cancel one quantum of quietness. To cancel
		685	both quiet flags, two (or more) minuses may be
		686	used:
		687
		688
		689	unzip -t--q zipfile
		690	unzip ---qt zipfile
		691
		692
		693	(the two are equivalent). This may seem awkward or
		694	confusing, but it is reasonably intuitive: just ignore the
		695	first hyphen and go from there. It is also consistent with
		696	the behavior of Unix nice(1).
		697
		698
		699	As suggested by the examples above, the default variable
		700	names are UNZIP_OPTS for VMS (where the symbol used to
		701	install ''unzip'' as a foreign command would otherwise be
		702	confused with the environment variable), and UNZIP for all
		703	other operating systems. For compatibility with
		704	''zip''(1L), UNZIPOPT is also accepted (don't ask). If
		705	both UNZIP and UNZIPOPT are defined, however, UNZIP takes
		706	precedence. ''unzip'''s diagnostic option (__-v__ with
		707	no zipfile name) can be used to check the values of all four
		708	possible ''unzip'' and ''zipinfo'' environment
		709	variables.
		710
		711
		712	The timezone variable (TZ) should be set according to the
		713	local timezone in order for the __-f__ and __-u__ to
		714	operate correctly. See the description of __-f__ above
		715	for details. This variable may also be necessary in order
		716	for timestamps on extracted files to be set correctly. Under
		717	Windows 95/NT ''unzip'' should know the correct timezone
		718	even if TZ is unset, assuming the timezone is correctly set
		719	in the Control Panel.
		720	!!DECRYPTION
		721
		722
		723	Encrypted archives are fully supported by Info-ZIP software,
		724	but due to United States export restrictions, de-/encryption
		725	support might be disabled in your compiled binary. However,
		726	since spring 2000, US export restrictions have been
		727	liberated, and our source archives do now include full crypt
		728	code. In case you need binary distributions with crypt
		729	support enabled, see the file ``WHERE'' in any Info-ZIP
		730	source or binary distribution for locations both inside and
		731	outside the US.
		732
		733
		734	Some compiled versions of ''unzip'' may not support
		735	decryption. To check a version for crypt support, either
		736	attempt to test or extract an encrypted archive, or else
		737	check ''unzip'''s diagnostic screen (see the __-v__
		738	option above) for ``[[decryption]'' as one of the
		739	special compilation options.
		740
		741
		742	As noted above, the __-P__ option may be used to supply a
		743	password on the command line, but at a cost in security. The
		744	preferred decryption method is simply to extract normally;
		745	if a zipfile member is encrypted, ''unzip'' will prompt
		746	for the password without echoing what is typed. ''unzip''
		747	continues to use the same password as long as it appears to
		748	be valid, by testing a 12-byte header on each file. The
		749	correct password will always check out against the header,
		750	but there is a 1-in-256 chance that an incorrect password
		751	will as well. (This is a security feature of the PKWARE
		752	zipfile format; it helps prevent brute-force attacks that
		753	might otherwise gain a large speed advantage by testing only
		754	the header.) In the case that an incorrect password is given
		755	but it passes the header test anyway, either an incorrect
		756	CRC will be generated for the extracted data or else
		757	''unzip'' will fail during the extraction because the
		758	``decrypted'' bytes do not constitute a valid compressed
		759	data stream.
		760
		761
		762	If the first password fails the header check on some file,
		763	''unzip'' will prompt for another password, and so on
		764	until all files are extracted. If a password is not known,
		765	entering a null password (that is, just a carriage return or
		766	``Enter'') is taken as a signal to skip all further
		767	prompting. Only unencrypted files in the archive(s) will
		768	thereafter be extracted. (In fact, that's not quite true;
		769	older versions of ''zip''(1L) and ''zipcloak''(1L)
		770	allowed null passwords, so ''unzip'' checks each
		771	encrypted file to see if the null password works. This may
		772	result in ``false positives'' and extraction errors, as
		773	noted above.)
		774
		775
		776	Archives encrypted with 8-bit passwords (for example,
		777	passwords with accented European characters) may not be
		778	portable across systems and/or other archivers. This problem
		779	stems from the use of multiple encoding methods for such
		780	characters, including Latin-1 (ISO 8859-1) and OEM code page
		781	850. DOS ''PKZIP'' 2.04g uses the OEM code page; Windows
		782	''PKZIP'' 2.50 uses Latin-1 (and is therefore
		783	incompatible with DOS ''PKZIP''); Info-ZIP uses the OEM
		784	code page on DOS, OS/2 and Win3.x ports but Latin-1
2	perry	785	everywhere else; and Nico Mak's ''!WinZip'' 6.x does not
		786	allow 8-bit passwords at all. ''!UnZip'' 5.3 (or newer)
1	perry	787	attempts to use the default character set first (e.g.,
		788	Latin-1), followed by the alternate one (e.g., OEM code
		789	page) to test passwords. On EBCDIC systems, if both of these
		790	fail, EBCDIC encoding will be tested as a last resort.
		791	(EBCDIC is not tested on non-EBCDIC systems, because there
		792	are no known archivers that encrypt using EBCDIC encoding.)
		793	ISO character encodings other than Latin-1 are not
		794	supported.
		795	!!EXAMPLES
		796
		797
		798	To use ''unzip'' to extract all members of the archive
		799	''letters.zip'' into the current directory and
		800	subdirectories below it, creating any subdirectories as
		801	necessary:
		802
		803
		804	unzip letters
		805
		806
		807	To extract all members of ''letters.zip'' into the
		808	current directory only:
		809
		810
		811	unzip -j letters
		812
		813
		814	To test ''letters.zip'', printing only a summary message
		815	indicating whether the archive is OK or not:
		816
		817
		818	unzip -tq letters
		819
		820
		821	To test ''all'' zipfiles in the current directory,
		822	printing only the summaries:
		823
		824
		825	unzip -tq *.zip
		826
		827
		828	(The backslash before the asterisk is only required if the
		829	shell expands wildcards, as in Unix; double quotes could
		830	have been used instead, as in the source examples below.) To
		831	extract to standard output all members of ''letters.zip''
		832	whose names end in ''.tex'', auto-converting to the local
		833	end-of-line convention and piping the output into
		834	more(1):
		835
		836
		837	unzip -ca letters *.tex | more
		838
		839
		840	To extract the binary file ''paper1.dvi'' to standard
		841	output and pipe it to a printing program:
		842
		843
		844	unzip -p articles paper1.dvi | dvips
		845
		846
		847	To extract all FORTRAN and C source files--*.f, *.c, *.h,
		848	and Makefile--into the /tmp directory:
		849
		850
		851	unzip source.zip
		852
		853
		854	(the double quotes are necessary only in Unix and only if
		855	globbing is turned on). To extract all FORTRAN and C source
		856	files, regardless of case (e.g., both *.c and *.C, and any
		857	makefile, Makefile, MAKEFILE or similar):
		858
		859
		860	unzip -C source.zip
		861
		862
		863	To extract any such files but convert any uppercase MS-DOS
		864	or VMS names to lowercase and convert the line-endings of
		865	all of the files to the local standard (without respect to
		866	any files that might be marked ``binary''):
		867
		868
		869	unzip -aaCL source.zip
		870
		871
		872	To extract only newer versions of the files already in the
		873	current directory, without querying (NOTE: be careful of
		874	unzipping in one timezone a zipfile created in another--ZIP
		875	archives other than those created by Zip 2.1 or later
		876	contain no timezone information, and a ``newer'' file from
		877	an eastern timezone may, in fact, be older):
		878
		879
		880	unzip -fo sources
		881
		882
		883	To extract newer versions of the files already in the
		884	current directory and to create any files not already there
		885	(same caveat as previous example):
		886
		887
		888	unzip -uo sources
		889
		890
		891	To display a diagnostic screen showing which ''unzip''
		892	and ''zipinfo'' options are stored in environment
		893	variables, whether decryption support was compiled in, the
		894	compiler with which ''unzip'' was compiled,
		895	etc.:
		896
		897
		898	unzip -v
		899
		900
		901	In the last five examples, assume that UNZIP or UNZIP_OPTS
		902	is set to -q. To do a singly quiet listing:
		903
		904
		905	unzip -l file.zip
		906
		907
		908	To do a doubly quiet listing:
		909
		910
		911	unzip -ql file.zip
		912
		913
		914	(Note that the ``.zip'' is generally not
		915	necessary.) To do a standard listing:
		916
		917
		918	unzip --ql file.zip
		919
		920
		921	or
		922
		923
		924	unzip -l-q file.zip
		925
		926
		927	or
		928
		929
		930	unzip -l--q file.zip
		931
		932
		933	(Extra minuses in options don't hurt.)
		934	!!TIPS
		935
		936
		937	The current maintainer, being a lazy sort, finds it very
		938	useful to define a pair of aliases: tt for
		939	``unzip -tq'' and ii for ``unzip
		940	-Z'' (or ``zipinfo''). One may then simply
		941	type ``tt zipfile'' to test an archive, something
		942	that is worth making a habit of doing. With luck
		943	''unzip'' will report ``No errors detected in
		944	compressed data of zipfile.zip,'' after which one may
		945	breathe a sigh of relief.
		946
		947
		948	The maintainer also finds it useful to set the UNZIP
		949	environment variable to ``-aL'' and is tempted to
		950	add ``-C'' as well. His ZIPINFO variable is set to
		951	``-z''.
		952	!!DIAGNOSTICS
		953
		954
		955	The exit status (or error level) approximates the exit codes
		956	defined by PKWARE and takes on the following values, except
		957	under VMS:
		958
		959
		960	0
		961
		962
		963	normal; no errors or warnings detected.
		964
		965
		966	1
		967
		968
		969	one or more warning errors were encountered, but processing
		970	completed successfully anyway. This includes zipfiles where
		971	one or more files was skipped due to unsupported compression
		972	method or encryption with an unknown password.
		973
		974
		975	2
		976
		977
		978	a generic error in the zipfile format was detected.
		979	Processing may have completed successfully anyway; some
		980	broken zipfiles created by other archivers have simple
		981	work-arounds.
		982
		983
		984	3
		985
		986
		987	a severe error in the zipfile format was detected.
		988	Processing probably failed immediately.
		989
		990
		991	4
		992
		993
		994	''unzip'' was unable to allocate memory for one or more
		995	buffers during program initialization.
		996
		997
		998	5
		999
		1000
		1001	''unzip'' was unable to allocate memory or unable to
		1002	obtain a tty to read the decryption
		1003	password(s).
		1004
		1005
		1006	6
		1007
		1008
		1009	''unzip'' was unable to allocate memory during
		1010	decompression to disk.
		1011
		1012
		1013	7
		1014
		1015
		1016	''unzip'' was unable to allocate memory during in-memory
		1017	decompression.
		1018
		1019
		1020	8
		1021
		1022
		1023	[[currently not used]
		1024
		1025
		1026	9
		1027
		1028
		1029	the specified zipfiles were not found.
		1030
		1031
		1032	10
		1033
		1034
		1035	invalid options were specified on the command
		1036	line.
		1037
		1038
		1039	11
		1040
		1041
		1042	no matching files were found.
		1043
		1044
		1045	50
		1046
		1047
		1048	the disk is (or was) full during extraction.
		1049
		1050
		1051	51
		1052
		1053
		1054	the end of the ZIP archive was encountered
		1055	prematurely.
		1056
		1057
		1058	80
		1059
		1060
		1061	the user aborted ''unzip'' prematurely with control-C (or
		1062	similar)
		1063
		1064
		1065	81
		1066
		1067
		1068	testing or extraction of one or more files failed due to
		1069	unsupported compression methods or unsupported
		1070	decryption.
		1071
		1072
		1073	82
		1074
		1075
		1076	no files were found due to bad decryption password(s). (If
		1077	even one file is successfully processed, however, the exit
		1078	status is 1.)
		1079
		1080
		1081	VMS interprets standard Unix (or PC) return values as other,
		1082	scarier-looking things, so ''unzip'' instead maps them
		1083	into VMS-style status codes. The current mapping is as
		1084	follows: 1 (success) for normal exit, 0x7fff0001 for warning
		1085	errors, and (0x7fff000? + 16*normal_unzip_exit_status) for
		1086	all other errors, where the `?' is 2 (error) for
		1087	''unzip'' values 2, 9-11 and 80-82, and 4 (fatal error)
		1088	for the remaining ones (3-8, 50, 51). In addition, there is
		1089	a compilation option to expand upon this behavior: defining
		1090	RETURN_CODES results in a human-readable explanation of what
		1091	the error status means.
		1092	!!BUGS
		1093
		1094
		1095	Multi-part archives are not yet supported, except in
		1096	conjunction with ''zip''. (All parts must be concatenated
		1097	together in order, and then ``zip -F'' must be
		1098	performed on the concatenated archive in order to ``fix''
		1099	it.) This will definitely be corrected in the next major
		1100	release.
		1101
		1102
		1103	Archives read from standard input are not yet supported,
		1104	except with ''funzip'' (and then only the first member of
		1105	the archive can be extracted).
		1106
		1107
		1108	Archives encrypted with 8-bit passwords (e.g., passwords
		1109	with accented European characters) may not be portable
		1110	across systems and/or other archivers. See the discussion in
		1111	__DECRYPTION__ above.
		1112
		1113
		1114	''unzip'''s __-M__ (``more'') option is overly
		1115	simplistic in its handling of screen output; as noted above,
		1116	it fails to detect the wrapping of long lines and may
		1117	thereby cause lines at the top of the screen to be scrolled
		1118	off before being read. ''unzip'' should detect and treat
		1119	each occurrence of line-wrap as one additional line printed.
		1120	This requires knowledge of the screen's width as well as its
		1121	height. In addition, ''unzip'' should detect the true
		1122	screen geometry on all systems.
		1123
		1124
		1125	Dates, times and permissions of stored directories are not
		1126	restored except under Unix.
		1127
		1128
		1129	[[MS-DOS] When extracting or testing files from an archive on
		1130	a defective floppy diskette, if the ``Fail'' option is
		1131	chosen from DOS's ``Abort, Retry, Fail?'' message, older
		1132	versions of ''unzip'' may hang the system, requiring a
		1133	reboot. This problem appears to be fixed, but control-C (or
		1134	control-Break) can still be used to terminate
		1135	''unzip''.
		1136
		1137
		1138	Under DEC Ultrix, ''unzip'' would sometimes fail on long
		1139	zipfiles (bad CRC, not always reproducible). This was
		1140	apparently due either to a hardware bug (cache memory) or an
		1141	operating system bug (improper handling of page faults?).
		1142	Since Ultrix has been abandoned in favor of Digital Unix
		1143	(OSF/1), this may not be an issue anymore.
		1144
		1145
		1146	[[Unix] Unix special files such as FIFO buffers (named
		1147	pipes), block devices and character devices are not restored
		1148	even if they are somehow represented in the zipfile, nor are
		1149	hard-linked files relinked. Basically the only file types
		1150	restored by ''unzip'' are regular files, directories and
		1151	symbolic (soft) links.
		1152
		1153
		1154	[[OS/2] Extended attributes for existing directories are only
		1155	updated if the __-o__ (``overwrite all'') option is
		1156	given. This is a limitation of the operating system; because
		1157	directories only have a creation time associated with them,
		1158	''unzip'' has no way to determine whether the stored
		1159	attributes are newer or older than those on disk. In
		1160	practice this may mean a two-pass approach is required:
		1161	first unpack the archive normally (with or without
		1162	freshening/updating existing files), then overwrite just the
		1163	directory entries (e.g., ``unzip -o foo
		1164	*/'').
		1165
		1166
		1167	[[VMS] When extracting to another directory, only the
		1168	''[[.foo]'' syntax is accepted for the __-d__ option;
		1169	the simple Unix ''foo'' syntax is silently ignored (as is
		1170	the less common VMS ''foo.dir'' syntax).
		1171
		1172
		1173	[[VMS] When the file being extracted already exists,
		1174	''unzip'''s query only allows skipping, overwriting or
		1175	renaming; there should additionally be a choice for creating
		1176	a new version of the file. In fact, the ``overwrite'' choice
		1177	does create a new version; the old version is not
		1178	overwritten or deleted.
		1179	!!SEE ALSO
		1180
		1181
		1182	''funzip''(1L), ''zip''(1L), ''zipcloak''(1L),
		1183	''zipgrep''(1L), ''zipinfo''(1L), ''zipnote''(1L),
		1184	''zipsplit''(1L)
		1185	!!URL
		1186
		1187
		1188	The Info-ZIP home page is currently at
		1189
		1190
		1191	http://www.info-zip.org/pub/infozip/
		1192
		1193
		1194	or
		1195
		1196
		1197	ftp://ftp.info-zip.org/pub/infozip/ .
		1198	!!AUTHORS
		1199
		1200
		1201	The primary Info-ZIP authors (current semi-active members of
		1202	the Zip-Bugs workgroup) are: Greg ``Cave Newt'' Roelofs
2	perry	1203	(!UnZip); Onno van der Linden (Zip); Jean-loup Gailly
1	perry	1204	(compression); Mark Adler (decompression, fUnZip); Christian
2	perry	1205	Spieler (!UnZip maintance coordination, VMS, MS-DOS, Windows
		1206	95, NT, shared code, general Zip and !UnZip integration and
1	perry	1207	optimization); Mike White (Windows GUI, Windows DLLs); Kai
		1208	Uwe Rommel (OS/2); Paul Kienitz (Amiga, Windows 95); Chris
		1209	Herborth (BeOS, QNX, Atari); Jonathan Hudson (SMS/QDOS);
		1210	Sergio Monesi (Acorn RISC OS); Harald Denker (Atari, MVS);
		1211	John Bush (Solaris, Amiga); Hunter Goatley (VMS); Steve
		1212	Salisbury (Windows 95, NT); Steve Miller (Windows CE GUI),
		1213	Johnny Lee (MS-DOS, Windows 95, NT); and Dave Smith (Tandem
		1214	NSK). The author of the original unzip code upon which
		1215	Info-ZIP's was based is Samuel H. Smith; Carl Mascott did
		1216	the first Unix port; and David P. Kirschbaum organized and
		1217	led Info-ZIP in its early days with Keith Petersen hosting
		1218	the original mailing list at WSMR-SimTel20. The full list of
2	perry	1219	contributors to !UnZip has grown quite large; please refer to
		1220	the CONTRIBS file in the !UnZip source distribution for a
1	perry	1221	relatively complete version.
		1222	!!VERSIONS
		1223
		1224
		1225	v1.2 15 Mar 89
		1226
		1227
		1228	Samuel H. Smith
		1229
		1230
		1231	v2.0 9 Sep 89
		1232
		1233
		1234	Samuel H. Smith
		1235
		1236
		1237	v2.x fall 1989
		1238
		1239
		1240	many Usenet contributors
		1241
		1242
		1243	v3.0 1 May 90
		1244
		1245
		1246	Info-ZIP (DPK, consolidator)
		1247
		1248
		1249	v3.1 15 Aug 90
		1250
		1251
		1252	Info-ZIP (DPK, consolidator)
		1253
		1254
		1255	v4.0 1 Dec 90
		1256
		1257
		1258	Info-ZIP (GRR, maintainer)
		1259
		1260
		1261	v4.1 12 May 91
		1262
		1263
		1264	Info-ZIP
		1265
		1266
		1267	v4.2 20 Mar 92
		1268
		1269
		1270	Info-ZIP (Zip-Bugs subgroup, GRR)
		1271
		1272
		1273	v5.0 21 Aug 92
		1274
		1275
		1276	Info-ZIP (Zip-Bugs subgroup, GRR)
		1277
		1278
		1279	v5.01 15 Jan 93
		1280
		1281
		1282	Info-ZIP (Zip-Bugs subgroup, GRR)
		1283
		1284
		1285	v5.1 7 Feb 94
		1286
		1287
		1288	Info-ZIP (Zip-Bugs subgroup, GRR)
		1289
		1290
		1291	v5.11 2 Aug 94
		1292
		1293
		1294	Info-ZIP (Zip-Bugs subgroup, GRR)
		1295
		1296
		1297	v5.12 28 Aug 94
		1298
		1299
		1300	Info-ZIP (Zip-Bugs subgroup, GRR)
		1301
		1302
		1303	v5.2 30 Apr 96
		1304
		1305
		1306	Info-ZIP (Zip-Bugs subgroup, GRR)
		1307
		1308
		1309	v5.3 22 Apr 97
		1310
		1311
		1312	Info-ZIP (Zip-Bugs subgroup, GRR)
		1313
		1314
		1315	v5.31 31 May 97
		1316
		1317
		1318	Info-ZIP (Zip-Bugs subgroup, GRR)
		1319
		1320
		1321	v5.32 3 Nov 97
		1322
		1323
		1324	Info-ZIP (Zip-Bugs subgroup, GRR)
		1325
		1326
		1327	v5.4 28 Nov 98
		1328
		1329
		1330	Info-ZIP (Zip-Bugs subgroup, SPC)
		1331
		1332
		1333	v5.41 16 Apr 00
		1334
		1335
		1336	Info-ZIP (Zip-Bugs subgroup, SPC)
		1337
		1338
		1339	v5.42 14 Jan 01
		1340
		1341
		1342	Info-ZIP (Zip-Bugs subgroup, SPC)
		1343
		1344
		1345	v5.5 17 Feb 02
		1346
		1347
		1348	Info-ZIP (Zip-Bugs subgroup, SPC)
		1349	----