zip(3erl) Erlang Module Definition zip(3erl)
NAME
zip - Utility for reading and creating 'zip' archives.
DESCRIPTION
This module archives and extracts files to and from a zip archive. The
zip format is specified by the "ZIP Appnote.txt" file, available on the
PKWARE web site www.pkware.com.
The zip module supports zip archive versions up to 6.1. However, pass-
word-protection and Zip64 are not supported.
By convention, the name of a zip file is to end with .zip. To abide to
the convention, add .zip to the filename.
* To create zip archives, use function zip/2 or zip/3. They are also
available as create/2,3, to resemble the erl_tar module.
* To extract files from a zip archive, use function unzip/1 or un-
zip/2. They are also available as extract/1,2, to resemble the
erl_tar module.
* To fold a function over all files in a zip archive, use function
foldl/3.
* To return a list of the files in a zip archive, use function
list_dir/1 or list_dir/2. They are also available as table/1,2, to
resemble the erl_tar module.
* To print a list of files to the Erlang shell, use function t/1 or
tt/1.
* Sometimes it is desirable to open a zip archive, and to unzip files
from it file by file, without having to reopen the archive. This
can be done by functions zip_open/1,2, zip_get/1,2, zip_list_dir/1,
and zip_close/1.
LIMITATIONS
* Zip64 archives are not supported.
* Password-protected and encrypted archives are not supported.
* Only the DEFLATE (zlib-compression) and the STORE (uncompressed
data) zip methods are supported.
* The archive size is limited to 2 GB (32 bits).
* Comments for individual files are not supported when creating zip
archives. The zip archive comment for the whole zip archive is sup-
ported.
* Changing a zip archive is not supported. To add or remove a file
from an archive, the whole archive must be recreated.
DATA TYPES
zip_comment() = #zip_comment{comment = string()}
The record zip_comment only contains the archive comment for a
zip archive.
zip_file() =
#zip_file{name = string(),
info = file:file_info(),
comment = string(),
offset = integer() >= 0,
comp_size = integer() >= 0}
The record zip_file contains the following fields:
name:
The filename
info:
File information as in file:read_file_info/1 in Kernel
comment:
The comment for the file in the zip archive
offset:
The file offset in the zip archive (used internally)
comp_size:
The size of the compressed file (the size of the uncom-
pressed file is found in info)
filename() = file:filename()
The name of a zip file.
extension() = string()
extension_spec() =
all |
[Extension :: extension()] |
{add, [Extension :: extension()]} |
{del, [Extension :: extension()]}
create_option() =
memory | cooked | verbose |
{comment, Comment :: string()} |
{cwd, CWD :: file:filename()} |
{compress, What :: extension_spec()} |
{uncompress, What :: extension_spec()}
These options are described in create/3.
handle()
As returned by zip_open/2.
EXPORTS
foldl(Fun, Acc0, Archive) -> {ok, Acc1} | {error, Reason}
Types:
Fun = fun((FileInArchive, GetInfo, GetBin, AccIn) -> AccOut)
FileInArchive = file:name()
GetInfo = fun(() -> file:file_info())
GetBin = fun(() -> binary())
Acc0 = Acc1 = AccIn = AccOut = term()
Archive = file:name() | {file:name(), binary()}
Reason = term()
Calls Fun(FileInArchive, GetInfo, GetBin, AccIn) on successive
files in the Archive, starting with AccIn == Acc0.
FileInArchive is the name that the file has in the archive.
GetInfo is a fun that returns information about the file.
GetBin returns the file contents.
Both GetInfo and GetBin must be called within the Fun. Their be-
havior is undefined if they are called outside the context of
Fun.
The Fun must return a new accumulator, which is passed to the
next call. foldl/3 returns the final accumulator value. Acc0 is
returned if the archive is empty. It is not necessary to iterate
over all files in the archive. The iteration can be ended prema-
turely in a controlled manner by throwing an exception.
Example:
> Name = "dummy.zip".
"dummy.zip"
> {ok, {Name, Bin}} = zip:create(Name, [{"foo", <<"FOO">>}, {"bar", <<"BAR">>}], [memory]).
{ok,{"dummy.zip",
<<80,75,3,4,20,0,0,0,0,0,74,152,97,60,171,39,212,26,3,0,
0,0,3,0,0,...>>}}
> {ok, FileSpec} = zip:foldl(fun(N, I, B, Acc) -> [{N, B(), I()} | Acc] end, [], {Name, Bin}).
{ok,[{"bar",<<"BAR">>,
{file_info,3,regular,read_write,
{{2010,3,1},{19,2,10}},
{{2010,3,1},{19,2,10}},
{{2010,3,1},{19,2,10}},
54,1,0,0,0,0,0}},
{"foo",<<"FOO">>,
{file_info,3,regular,read_write,
{{2010,3,1},{19,2,10}},
{{2010,3,1},{19,2,10}},
{{2010,3,1},{19,2,10}},
54,1,0,0,0,0,0}}]}
> {ok, {Name, Bin}} = zip:create(Name, lists:reverse(FileSpec), [memory]).
{ok,{"dummy.zip",
<<80,75,3,4,20,0,0,0,0,0,74,152,97,60,171,39,212,26,3,0,
0,0,3,0,0,...>>}}
> catch zip:foldl(fun("foo", _, B, _) -> throw(B()); (_,_,_,Acc) -> Acc end, [], {Name, Bin}).
<<"FOO">>
list_dir(Archive) -> RetValue
list_dir(Archive, Options) -> RetValue
table(Archive) -> RetValue
table(Archive, Options) -> RetValue
Types:
Archive = file:name() | binary()
RetValue = {ok, CommentAndFiles} | {error, Reason :: term()}
CommentAndFiles = [zip_comment() | zip_file()]
Options = [Option]
Option = cooked
list_dir/1 retrieves all filenames in the zip archive Archive.
list_dir/2 provides options.
table/1 and table/2 are provided as synonyms to resemble the
erl_tar module.
The result value is the tuple {ok, List}, where List contains
the zip archive comment as the first element.
One option is available:
cooked:
By default, this function opens the zip file in raw mode,
which is faster but does not allow a remote (Erlang) file
server to be used. Adding cooked to the mode list overrides
the default and opens the zip file without option raw.
t(Archive) -> ok
Types:
Archive = file:name() | binary() | ZipHandle
ZipHandle = handle()
Prints all filenames in the zip archive Archive to the Erlang
shell. (Similar to tar t.)
tt(Archive) -> ok
Types:
Archive = file:name() | binary() | ZipHandle
ZipHandle = handle()
Prints filenames and information about all files in the zip ar-
chive Archive to the Erlang shell. (Similar to tar tv.)
unzip(Archive) -> RetValue
unzip(Archive, Options) -> RetValue
extract(Archive) -> RetValue
extract(Archive, Options) -> RetValue
Types:
Archive = file:name() | binary()
Options = [Option]
Option =
{file_list, FileList} |
keep_old_files | verbose | memory |
{file_filter, FileFilter} |
{cwd, CWD}
FileList = [file:name()]
FileBinList = [{file:name(), binary()}]
FileFilter = fun((ZipFile) -> boolean())
CWD = file:filename()
ZipFile = zip_file()
RetValue =
{ok, FileList} |
{ok, FileBinList} |
{error, Reason :: term()} |
{error, {Name :: file:name(), Reason :: term()}}
unzip/1 extracts all files from a zip archive.
unzip/2 provides options to extract some files, and more.
extract/1 and extract/2 are provided as synonyms to resemble
module erl_tar.
If argument Archive is specified as a binary, the contents of
the binary is assumed to be a zip archive, otherwise a filename.
Options:
{file_list, FileList}:
By default, all files are extracted from the zip archive.
With option {file_list, FileList}, function unzip/2 only ex-
tracts the files whose names are included in FileList. The
full paths, including the names of all subdirectories within
the zip archive, must be specified.
cooked:
By default, this function opens the zip file in raw mode,
which is faster but does not allow a remote (Erlang) file
server to be used. Adding cooked to the mode list overrides
the default and opens the zip file without option raw. The
same applies for the files extracted.
keep_old_files:
By default, all files with the same name as files in the zip
archive are overwritten. With option keep_old_files set,
function unzip/2 does not overwrite existing files. Notice
that even with option memory specified, which means that no
files are overwritten, existing files are excluded from the
result.
verbose:
Prints an informational message for each extracted file.
memory:
Instead of extracting to the current directory, the result
is given as a list of tuples {Filename, Binary}, where Bi-
nary is a binary containing the extracted data of file File-
name in the zip archive.
{cwd, CWD}:
Uses the specified directory as current directory. It is
prepended to filenames when extracting them from the zip ar-
chive. (Acting like file:set_cwd/1 in Kernel, but without
changing the global cwd property.)
zip(Name, FileList) -> RetValue
zip(Name, FileList, Options) -> RetValue
create(Name, FileList) -> RetValue
create(Name, FileList, Options) -> RetValue
Types:
Name = file:name()
FileList = [FileSpec]
FileSpec =
file:name() |
{file:name(), binary()} |
{file:name(), binary(), file:file_info()}
Options = [Option]
Option = create_option()
RetValue =
{ok, FileName :: filename()} |
{ok, {FileName :: filename(), binary()}} |
{error, Reason :: term()}
create_option() =
memory | cooked | verbose |
{comment, Comment :: string()} |
{cwd, CWD :: file:filename()} |
{compress, What :: extension_spec()} |
{uncompress, What :: extension_spec()}
extension_spec() =
all |
[Extension :: extension()] |
{add, [Extension :: extension()]} |
{del, [Extension :: extension()]}
Creates a zip archive containing the files specified in
FileList.
create/2 and create/3 are provided as synonyms to resemble mod-
ule erl_tar.
FileList is a list of files, with paths relative to the current
directory, which are stored with this path in the archive. Files
can also be specified with data in binaries to create an archive
directly from data.
Files are compressed using the DEFLATE compression, as described
in the "Appnote.txt" file. However, files are stored without
compression if they are already compressed. zip/2 and zip/3
check the file extension to determine if the file is to be
stored without compression. Files with the following extensions
are not compressed: .Z, .zip, .zoo, .arc, .lzh, .arj.
It is possible to override the default behavior and control what
types of files that are to be compressed by using options {com-
press, What} and {uncompress, What}. It is also possible to use
many compress and uncompress options.
To trigger file compression, its extension must match with the
compress condition and must not match the uncompress condition.
For example, if compress is set to ["gif", "jpg"] and uncompress
is set to ["jpg"], only files with extension "gif" are com-
pressed.
Options:
cooked:
By default, this function opens the zip file in mode raw,
which is faster but does not allow a remote (Erlang) file
server to be used. Adding cooked to the mode list overrides
the default and opens the zip file without the raw option.
The same applies for the files added.
verbose:
Prints an informational message about each added file.
memory:
The output is not to a file, but instead as a tuple {File-
Name, binary()}. The binary is a full zip archive with
header and can be extracted with, for example, unzip/2.
{comment, Comment}:
Adds a comment to the zip archive.
{cwd, CWD}:
Uses the specified directory as current work directory
(cwd). This is prepended to filenames when adding them, al-
though not in the zip archive (acting like file:set_cwd/1 in
Kernel, but without changing the global cwd property.).
{compress, What}:
Controls what types of files to be compressed. Defaults to
all. The following values of What are allowed:
all:
All files are compressed (as long as they pass the uncom-
press condition).
[Extension]:
Only files with exactly these extensions are compressed.
{add,[Extension]}:
Adds these extensions to the list of compress extensions.
{del,[Extension]}:
Deletes these extensions from the list of compress exten-
sions.
{uncompress, What}:
Controls what types of files to be uncompressed. Defaults to
[".Z", ".zip", ".zoo", ".arc", ".lzh", ".arj"]. The follow-
ing values of What are allowed:
all:
No files are compressed.
[Extension]:
Files with these extensions are uncompressed.
{add,[Extension]}:
Adds these extensions to the list of uncompress exten-
sions.
{del,[Extension]}:
Deletes these extensions from the list of uncompress ex-
tensions.
zip_close(ZipHandle) -> ok | {error, einval}
Types:
ZipHandle = handle()
Closes a zip archive, previously opened with zip_open/1,2. All
resources are closed, and the handle is not to be used after
closing.
zip_get(ZipHandle) -> {ok, [Result]} | {error, Reason}
zip_get(FileName, ZipHandle) -> {ok, Result} | {error, Reason}
Types:
FileName = file:name()
ZipHandle = handle()
Result = file:name() | {file:name(), binary()}
Reason = term()
Extracts one or all files from an open archive.
The files are unzipped to memory or to file, depending on the
options specified to function zip_open/1,2 when opening the ar-
chive.
zip_list_dir(ZipHandle) -> {ok, Result} | {error, Reason}
Types:
Result = [zip_comment() | zip_file()]
ZipHandle = handle()
Reason = term()
Returns the file list of an open zip archive. The first returned
element is the zip archive comment.
zip_open(Archive) -> {ok, ZipHandle} | {error, Reason}
zip_open(Archive, Options) -> {ok, ZipHandle} | {error, Reason}
Types:
Archive = file:name() | binary()
ZipHandle = handle()
Options = [Option]
Option = cooked | memory | {cwd, CWD :: file:filename()}
Reason = term()
Opens a zip archive, and reads and saves its directory. This
means that later reading files from the archive is faster than
unzipping files one at a time with unzip/1,2.
The archive must be closed with zip_close/1.
The ZipHandle is closed if the process that originally opened
the archive dies.
Ericsson AB stdlib 3.13 zip(3erl)