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diff --git a/chromium/third_party/cygwin/lib/perl5/vendor_perl/5.10/Archive/Zip/FAQ.pod b/chromium/third_party/cygwin/lib/perl5/vendor_perl/5.10/Archive/Zip/FAQ.pod deleted file mode 100644 index 2d2e1ab408d..00000000000 --- a/chromium/third_party/cygwin/lib/perl5/vendor_perl/5.10/Archive/Zip/FAQ.pod +++ /dev/null @@ -1,467 +0,0 @@ - -=head1 NAME - - -Archive::Zip::FAQ - Answers to a few frequently asked questions about Archive::Zip - -=head1 DESCRIPTION - - -It seems that I keep answering the same questions over and over again. I -assume that this is because my documentation is deficient, rather than that -people don't read the documentation. - - -So this FAQ is an attempt to cut down on the number of personal answers I have -to give. At least I can now say "You I<did> read the FAQ, right?". - - -The questions are not in any particular order. The answers assume the current -version of Archive::Zip; some of the answers depend on newly added/fixed -functionality. - -=head1 Install problems on RedHat 8 or 9 with Perl 5.8.0 - - -B<Q:> Archive::Zip won't install on my RedHat 9 system! It's broke! - - -B<A:> This has become something of a FAQ. -Basically, RedHat broke some versions of Perl by setting LANG to UTF8. -They apparently have a fixed version out as an update. - -You might try running CPAN or creating your Makefile after exporting the LANG -environment variable as - -C<LANG=C> - -L<https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=87682> - - -=head1 Why is my zip file so big? - - -B<Q:> My zip file is actually bigger than what I stored in it! Why? - - -B<A:> Some things to make sure of: - -=over 4 - -=item Make sure that you are requesting COMPRESSION_DEFLATED if you are storing strings. - - - - -$member->desiredCompressionMethod( COMPRESSION_DEFLATED ); - - -=item Don't make lots of little files if you can help it. - - - -Since zip computes the compression tables for each member, small -members without much entropy won't compress well. Instead, if you've -got lots of repeated strings in your data, try to combine them into -one big member. - - -=item Make sure that you are requesting COMPRESSION_STORED if you are storing things that are already compressed. - - - -If you're storing a .zip, .jpg, .mp3, or other compressed file in a zip, -then don't compress them again. They'll get bigger. - -=back - -=head1 Sample code? - - -B<Q:> Can you send me code to do (whatever)? - - -B<A:> Have you looked in the C<examples/> directory yet? It contains: - -=over 4 - -=item examples/calcSizes.pl -- How to find out how big a Zip file will be before writing it - - - -=item examples/copy.pl -- Copies one Zip file to another - - - -=item examples/extract.pl -- extract file(s) from a Zip - - - -=item examples/mailZip.pl -- make and mail a zip file - - - -=item examples/mfh.pl -- demo for use of MockFileHandle - - - -=item examples/readScalar.pl -- shows how to use IO::Scalar as the source of a Zip read - - - -=item examples/selfex.pl -- a brief example of a self-extracting Zip - - - -=item examples/unzipAll.pl -- uses Archive::Zip::Tree to unzip an entire Zip - - - -=item examples/updateZip.pl -- shows how to read/modify/write a Zip - - - -=item examples/updateTree.pl -- shows how to update a Zip in place - - - -=item examples/writeScalar.pl -- shows how to use IO::Scalar as the destination of a Zip write - - - -=item examples/writeScalar2.pl -- shows how to use IO::String as the destination of a Zip write - - - -=item examples/zip.pl -- Constructs a Zip file - - - -=item examples/zipcheck.pl -- One way to check a Zip file for validity - - - -=item examples/zipinfo.pl -- Prints out information about a Zip archive file - - - -=item examples/zipGrep.pl -- Searches for text in Zip files - - - -=item examples/ziptest.pl -- Lists a Zip file and checks member CRCs - - - -=item examples/ziprecent.pl -- Puts recent files into a zipfile - - - -=item examples/ziptest.pl -- Another way to check a Zip file for validity - - - -=back - -=head1 Can't Read/modify/write same Zip file - - -B<Q:> Why can't I open a Zip file, add a member, and write it back? I get an -error message when I try. - - -B<A:> Because Archive::Zip doesn't (and can't, generally) read file contents into memory, -the original Zip file is required to stay around until the writing of the new -file is completed. - - -The best way to do this is to write the Zip to a temporary file and then -rename the temporary file to have the old name (possibly after deleting the -old one). - - -Archive::Zip v1.02 added the archive methods C<overwrite()> and -C<overwriteAs()> to do this simply and carefully. - - -See C<examples/updateZip.pl> for an example of this technique. - -=head1 File creation time not set - - -B<Q:> Upon extracting files, I see that their modification (and access) times are -set to the time in the Zip archive. However, their creation time is not set to -the same time. Why? - - -B<A:> Mostly because Perl doesn't give cross-platform access to I<creation time>. -Indeed, many systems (like Unix) don't support such a concept. -However, if yours does, you can easily set it. Get the modification time from -the member using C<lastModTime()>. - -=head1 Can't use Archive::Zip on gzip files - - -B<Q:> Can I use Archive::Zip to extract Unix gzip files? - - -B<A:> No. - - -There is a distinction between Unix gzip files, and Zip archives that -also can use the gzip compression. - - -Depending on the format of the gzip file, you can use L<Compress::Zlib>, or -L<Archive::Tar> to decompress it (and de-archive it in the case of Tar files). - - -You can unzip PKZIP/WinZip/etc/ archives using Archive::Zip (that's what -it's for) as long as any compressed members are compressed using -Deflate compression. - -=head1 Add a directory/tree to a Zip - - -B<Q:> How can I add a directory (or tree) full of files to a Zip? - - -B<A:> You can use the Archive::Zip::addTree*() methods: - - use Archive::Zip; - my $zip = Archive::Zip->new(); - # add all readable files and directories below . as xyz/* - $zip->addTree( '.', 'xyz' ); - # add all readable plain files below /abc as def/* - $zip->addTree( '/abc', 'def', sub { -f && -r } ); - # add all .c files below /tmp as stuff/* - $zip->addTreeMatching( '/tmp', 'stuff', '\.c$' ); - # add all .o files below /tmp as stuff/* if they aren't writable - $zip->addTreeMatching( '/tmp', 'stuff', '\.o$', sub { ! -w } ); - # add all .so files below /tmp that are smaller than 200 bytes as stuff/* - $zip->addTreeMatching( '/tmp', 'stuff', '\.o$', sub { -s < 200 } ); - # and write them into a file - $zip->writeToFileNamed('xxx.zip'); - -=head1 Extract a directory/tree - - -B<Q:> How can I extract some (or all) files from a Zip into a different -directory? - - -B<A:> You can use the Archive::Zip::extractTree() method: -??? || - - - # now extract the same files into /tmpx - $zip->extractTree( 'stuff', '/tmpx' ); - -=head1 Update a directory/tree - - -B<Q:> How can I update a Zip from a directory tree, adding or replacing only -the newer files? - - -B<A:> You can use the Archive::Zip::updateTree() method that was added in version 1.09. - -=head1 Zip times might be off by 1 second - - -B<Q:> It bothers me greatly that my file times are wrong by one second about half -the time. Why don't you do something about it? - - -B<A:> Get over it. This is a result of the Zip format storing times in DOS -format, which has a resolution of only two seconds. - -=head1 Zip times don't include time zone information - - -B<Q:> My file times don't respect time zones. What gives? - - -B<A:> If this is important to you, please submit patches to read the various -Extra Fields that encode times with time zones. I'm just using the DOS -Date/Time, which doesn't have a time zone. - -=head1 How do I make a self-extracting Zip - - -B<Q:> I want to make a self-extracting Zip file. Can I do this? - - -B<A:> Yes. You can write a self-extracting archive stub (that is, a version of -unzip) to the output filehandle that you pass to writeToFileHandle(). See -examples/selfex.pl for how to write a self-extracting archive. - - -However, you should understand that this will only work on one kind of -platform (the one for which the stub was compiled). - -=head1 How can I deal with Zips with prepended garbage (i.e. from Sircam) - - -B<Q:> How can I tell if a Zip has been damaged by adding garbage to the -beginning or inside the file? - - -B<A:> I added code for this for the Amavis virus scanner. You can query archives -for their 'eocdOffset' property, which should be 0: - - - if ($zip->eocdOffset > 0) - { warn($zip->eocdOffset . " bytes of garbage at beginning or within Zip") } - - -When members are extracted, this offset will be used to adjust the start of -the member if necessary. - -=head1 Can't extract Shrunk files - - -B<Q:> I'm trying to extract a file out of a Zip produced by PKZIP, and keep -getting this error message: - - - error: Unsupported compression combination: read 6, write 0 - - -B<A:> You can't uncompress this archive member. Archive::Zip only supports uncompressed -members, and compressed members that are compressed using the compression -supported by Compress::Zlib. That means only Deflated and Stored members. - - -Your file is compressed using the Shrink format, which isn't supported by -Compress::Zlib. - - -You could, perhaps, use a command-line UnZip program (like the Info-Zip -one) to extract this. - -=head1 Can't do decryption - - -B<Q:> How do I decrypt encrypted Zip members? - - -B<A:> With some other program or library. Archive::Zip doesn't support decryption, -and probably never will (unless I<you> write it). - -=head1 How to test file integrity? - - -B<Q:> How can Archive::Zip can test the validity of a Zip file? - - -B<A:> If you try to decompress the file, the gzip streams will report errors -if you have garbage. Most of the time. - -If you try to open the file and a central directory structure can't be -found, an error will be reported. - -When a file is being read, if we can't find a proper PK.. signature in -the right places we report a format error. - -If there is added garbage at the beginning of a Zip file (as inserted -by some viruses), you can find out about it, but Archive::Zip will ignore it, -and you can still use the archive. When it gets written back out the -added stuff will be gone. - - -There are two ready-to-use utilities in the examples directory that can -be used to test file integrity, or that you can use as examples -for your own code: - -=over 4 - -=item examples/zipcheck.pl shows how to use an attempted extraction to test a file. - - - -=item examples/ziptest.pl shows how to test CRCs in a file. - - - -=back - -=head1 Duplicate files in Zip? - - -B<Q:> Archive::Zip let me put the same file in my Zip twice! Why don't you prevent this? - - -B<A:> As far as I can tell, this is not disallowed by the Zip spec. If you -think it's a bad idea, check for it yourself: - - - $zip->addFile($someFile, $someName) unless $zip->memberNamed($someName); - - -I can even imagine cases where this might be useful (for instance, multiple -versions of files). - -=head1 File ownership/permissions/ACLS/etc - - -B<Q:> Why doesn't Archive::Zip deal with file ownership, ACLs, etc.? - - -B<A:> There is no standard way to represent these in the Zip file format. If -you want to send me code to properly handle the various extra fields that -have been used to represent these through the years, I'll look at it. - -=head1 I can't compile but ActiveState only has an old version of Archive::Zip - - -B<Q:> I've only installed modules using ActiveState's PPM program and -repository. But they have a much older version of Archive::Zip than is in CPAN. Will -you send me a newer PPM? - - -B<A:> Probably not, unless I get lots of extra time. But there's no reason you -can't install the version from CPAN. Archive::Zip is pure Perl, so all you need is -NMAKE, which you can get for free from Microsoft (see the FAQ in the -ActiveState documentation for details on how to install CPAN modules). - -=head1 My JPEGs (or MP3's) don't compress when I put them into Zips! - - -B<Q:> How come my JPEGs and MP3's don't compress much when I put them into Zips? - - -B<A:> Because they're already compressed. - -=head1 Under Windows, things lock up/get damaged - - -B<Q:> I'm using Windows. When I try to use Archive::Zip, my machine locks up/makes -funny sounds/displays a BSOD/corrupts data. How can I fix this? - - -B<A:> First, try the newest version of Compress::Zlib. I know of -Windows-related problems prior to v1.14 of that library. - - -If that doesn't get rid of the problem, fix your computer or get rid of -Windows. - -=head1 Zip contents in a scalar - - -B<Q:> I want to read a Zip file from (or write one to) a scalar variable instead -of a file. How can I do this? - - -B<A:> Use C<IO::String> and the C<readFromFileHandle()> and -C<writeToFileHandle()> methods. -See C<examples/readScalar.pl> and C<examples/writeScalar.pl>. - -=head1 Reading from streams - - -B<Q:> How do I read from a stream (like for the Info-Zip C<funzip> program)? - - -B<A:> This isn't currently supported, though writing to a stream is. |