1MDV::Packdrakeng(3) User Contributed Perl Documentation MDV::Packdrakeng(3)
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6 MDV::Packdrakeng - Simple Archive Extractor/Builder
7
9 use MDV::Packdrakeng;
10 # creating an archive
12 $pack = MDV::Packdrakeng->new(archive => "myarchive.cz");
13 # Adding a few files
14 $pack->add("/path/", "file1", "file2");
15 # Adding an unamed file
16 open($handle, "file");
17 $pack->add_virtual("filename", $handle);
18 close($handle);
19 $pack = undef;
21 # extracting an archive
23 $pack = MDV::Packdrakeng->open(archive => "myarchive.cz");
24 # listing files
25 $pack->list();
26 # extracting few files
27 $pack->extract("/path/", "file1", "file2");
28 # extracting data into a file handle
29 open($handle, "file");
30 $pack->extract_virtual($handle, "filename");
31 close($handle);
32
34 "MDV::Packdrakeng" is a simple indexed archive builder and extractor
35 using standard compression methods.
36
38 Compressed data are stored by block. For example,
39 UncompresseddatA1UncompresseddatA2 UncompresseddatA3UncompresseddatA4
41 |--- size 1 ---||--- size 2 ---| |--- size 3 ---||--- size 4 ---|
42 |<-offset1 |<-offset2 |<-offset3 |<-offset4
43 gives:
45 CompresseD1CompresseD2 CompresseD3CompresseD4
47 |--- c. size 1, 2 ---| |--- c. size 3, 4 ---|
48 |<-c. offset 1, 2 |<-c. offset 3, 4
49 A new block is started when its size exceeds the "block_size" value.
51 Compressed data are followed by the table of contents (toc), that is, a
53 simple list of packed files. Each file name is terminated by the "\n"
54 character:
55 dir1
57 dir2
58 ...
59 dirN
60 symlink1
61 point_file1
62 symlink2
63 point_file2
64 ...
65 ...
66 symlinkN
67 point_fileN
68 file1
69 file2
70 ...
71 fileN
72 The file sizes follows, 4 values are stored for each file: offset into
74 archive of compressed block, size of compressed block, offset into
75 block of the file and the file's size.
76 Finally the archive contains a 64-byte trailer, about the toc and the
78 archive itself:
79 'cz[0', strings 4 bytes
81 number of directory, 4 bytes
82 number of symlinks, 4 bytes
83 number of files, 4 bytes
84 the toc size, 4 bytes
85 the uncompression command, string of 40 bytes length
86 '0]cz', string 4 bytes
87
89 new(%options)
90 Creates a new archive. Options:
91 archive
93 The file name of the archive. If the file doesn't exist, it will
94 be created, else it will be owerwritten. See "open".
95 compress
97 The application to use to compress, if unspecified, gzip is used.
98 uncompress
100 The application used to extract data from archive. This option is
101 useless if you're opening an existing archive (unless you want to
102 force it). If unset, this value is based on compress command
103 followed by '-d' argument.
104 extern
106 If you're using gzip, by default MDV::Packdrakeng will use perl-
107 zlib to save system ressources. This option forces
108 MDV::Packdrakeng to use the external gzip command. This has no
109 meaning with other compress programs as internal functions are
110 not implemented yet.
111 comp_level
113 The compression level passed as an argument to the compression
114 program. By default, this is set to 6.
115 block_size
117 The limit size after which we start a new compressed block. The
118 default value is 400KB. Set it to 0 to be sure a new block will
119 be started for each packed files, and -1 to never start a new
120 block. Be aware that a big block size will slow down the file
121 extraction.
122 quiet
124 Do not output anything, shut up.
125 debug
127 Print debug messages.
128 open(%options)
130 Opens an existing archive for extracting or adding files.
131 The uncompression command is found into the archive, and the
133 compression command is deduced from it.
134 If you add files, a new compressed block will be started even if the
136 last block is smaller than the value of the "block_size" option. If
137 some compression options can't be found in the archive, the new
138 preference will be applied.
139 Options are the same than for the "new()" function.
141 MDV::Packdrakeng->add_virtual($type, $filename, $data)
143 Adds a file into archive according passed information. $type gives
144 the type of the file:
145 - 'd', the file will be a directory, store as '$filename'. $data is not used.
147 - 'l', the file will be a symlink named $filename, pointing to the file whose path
148 is given by the string $data.
149 - 'f', the file is a normal file, $filename will be its name, $data is either
150 an handle to open file, data will be read from current position to the
151 end of file, either a string to push as the content of the file.
152 MDV::Packdrakeng->add($prefix, @files)
154 Adds @files into archive located into $prefix. Only directory, files
155 and symlink will be added. For each file, the path should be relative
156 to $prefix and is stored as is.
157 MDV::Packdrakeng->extract_virtual(*HANDLE, $filename)
159 Extracts $filename data from archive into the *HANDLE. $filename
160 should be a normal file.
161 MDV::Packdrakeng->extract($destdir, @files)
163 Extracts @files from the archive into $destdir prefix.
164 MDV::Packdrakeng->getcontent()
166 Returns three arrayrefs describing files files into archive,
167 respectively directory list, files list and symlink list.
168 MDV::Packdrakeng->infofile($file)
170 Returns type and information about a given file into the archive;
171 that is:
172 - 'f' and the the size of the file for a plain file
174 - 'l' and the linked file for a symlink
175 - 'd' and undef for a directory
176 - undef if the file can't be found into archive.
177 MDV::Packdrakeng->infofile($handle)
179 Print to $handle (STDOUT if not specified) the content of the
180 archive.
181 MDV::Packdrakeng->dumptoc($handle)
183 Print to $handle (STDOUT if not specified) the table of content of
184 the archive.
185
187 1.10
188 use an oo code
189 add_virtual() now accept a string as file content
190
192 Olivier Thauvin <nanardon@mandriva.org>, Rafael Garcia-Suarez
193 <rgarciasuarez@mandriva.com>
194 Copyright (c) 2005 Mandriva
196 This module is a from scratch-rewrite of the original "packdrake"
198 utility. Its format is fully compatible with the old packdrake.
199
201 This program is free software; you can redistribute it and/or modify it
202 under the terms of GNU General Public License as published by the Free
203 Software Foundation; either version 2 of the License, or (at your
204 option) any later version.
205 This program is distributed in the hope that it will be useful, but
207 WITHOUT ANY WARRANTY; without even the implied warranty of
208 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
209 General Public License for more details.
210 If you do not have a copy of the GNU General Public License write to
212 the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
213 USA.
214perl v5.34.0 2021-07-22 MDV::Packdrakeng(3)