Introduction to UnZip
The UnZip package contains
ZIP extraction utilities. These are
useful for extracting files from ZIP
archives. ZIP archives are created
with PKZIP or Info-ZIP utilities, primarily in a DOS
environment.
![[Note]](../images/note.png)
Note
Development versions of BLFS may not build or run some packages
properly if LFS or dependencies have been updated since the most
recent stable versions of the books.
![[Caution]](../images/caution.png)
Caution
The previous version of the UnZip package had some locale related
issues. Currently there are no BLFS editors capable of testing
these locale issues. Therefore, the locale related information is
left on this page, but has not been tested. A more general
discussion of these problems can be found in the
Program Assumes Encoding section of the Locale Related Issues page.
Package Information
Additional Downloads
UnZip
Locale Issues
Note
Use of UnZip in the JDK, Mozilla, DocBook or any other BLFS package
installation is not a problem, as BLFS instructions never use
UnZip to extract a file with
non-ASCII characters in the file's name.
These issues are thought to be fixed in the patch. But since none
of the editors have data to test this, the following workarounds
are retained in case they might still be needed.
The UnZip package assumes that
filenames stored in the ZIP archives created on non-Unix systems
are encoded in CP850, and that they should be converted to
ISO-8859-1 when writing files onto the filesystem. Such assumptions
are not always valid. In fact, inside the ZIP archive, filenames
are encoded in the DOS codepage that is in use in the relevant
country, and the filenames on disk should be in the locale
encoding. In MS Windows, the OemToChar() C function (from
User32.DLL) does the correct
conversion (which is indeed the conversion from CP850 to a superset
of ISO-8859-1 if MS Windows is set up to use the US English
language), but there is no equivalent in Linux.
When using unzip to
unpack a ZIP archive containing non-ASCII filenames, the filenames
are damaged because unzip uses improper conversion
when any of its encoding assumptions are incorrect. For example, in
the ru_RU.KOI8-R locale, conversion of filenames from CP866 to
KOI8-R is required, but conversion from CP850 to ISO-8859-1 is
done, which produces filenames consisting of undecipherable
characters instead of words (the closest equivalent understandable
example for English-only users is rot13). There are several ways
around this limitation:
1) For unpacking ZIP archives with filenames containing non-ASCII
characters, use WinZip while running the Wine Windows emulator.
2) Use bsdtar -xf
from libarchive-3.7.7 to unpack the ZIP archive.
Then fix the damage made to the filenames using the convmv tool (https://j3e.de/linux/convmv/).
The following is an example for the zh_CN.UTF-8 locale:
convmv -f cp936 -t utf-8 -r --nosmart --notest \
</path/to/unzipped/files>
Installation of UnZip
First apply the patches:
patch -Np1 -i ../unzip-6.0-consolidated_fixes-1.patch
patch -Np1 -i ../unzip-6.0-gcc14-1.patch
Now compile the package:
make -f unix/Makefile generic
The test suite does not work for target generic.
Now, as the root user:
make prefix=/usr MANDIR=/usr/share/man/man1 \
-f unix/Makefile install
Command Explanations
make -f unix/Makefile
generic: This target begins by running a configure
script (unlike the older targets such as linux and linux_noasm)
which creates a flags file that is then used in the build. This
ensures that the 32-bit x86 build receives the right flags to unzip
files which are larger than 2 GB when extracted.