1081 lines
		
	
	
		
			45 KiB
		
	
	
	
		
			Markdown
		
	
	
	
			
		
		
	
	
			1081 lines
		
	
	
		
			45 KiB
		
	
	
	
		
			Markdown
		
	
	
	
# node-tar
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Fast and full-featured Tar for Node.js
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The API is designed to mimic the behavior of `tar(1)` on unix systems.
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If you are familiar with how tar works, most of this will hopefully be
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straightforward for you.  If not, then hopefully this module can teach
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you useful unix skills that may come in handy someday :)
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## Background
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A "tar file" or "tarball" is an archive of file system entries
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(directories, files, links, etc.)  The name comes from "tape archive".
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If you run `man tar` on almost any Unix command line, you'll learn
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quite a bit about what it can do, and its history.
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Tar has 5 main top-level commands:
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* `c` Create an archive
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* `r` Replace entries within an archive
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* `u` Update entries within an archive (ie, replace if they're newer)
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* `t` List out the contents of an archive
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* `x` Extract an archive to disk
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The other flags and options modify how this top level function works.
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## High-Level API
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These 5 functions are the high-level API.  All of them have a
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single-character name (for unix nerds familiar with `tar(1)`) as well
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as a long name (for everyone else).
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All the high-level functions take the following arguments, all three
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of which are optional and may be omitted.
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1. `options` - An optional object specifying various options
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2. `paths` - An array of paths to add or extract
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3. `callback` - Called when the command is completed, if async.  (If
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   sync or no file specified, providing a callback throws a
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   `TypeError`.)
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If the command is sync (ie, if `options.sync=true`), then the
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callback is not allowed, since the action will be completed immediately.
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If a `file` argument is specified, and the command is async, then a
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`Promise` is returned.  In this case, if async, a callback may be
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provided which is called when the command is completed.
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If a `file` option is not specified, then a stream is returned.  For
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`create`, this is a readable stream of the generated archive.  For
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`list` and `extract` this is a writable stream that an archive should
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be written into.  If a file is not specified, then a callback is not
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allowed, because you're already getting a stream to work with.
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`replace` and `update` only work on existing archives, and so require
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a `file` argument.
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Sync commands without a file argument return a stream that acts on its
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input immediately in the same tick.  For readable streams, this means
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that all of the data is immediately available by calling
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`stream.read()`.  For writable streams, it will be acted upon as soon
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as it is provided, but this can be at any time.
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### Warnings and Errors
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Tar emits warnings and errors for recoverable and unrecoverable situations,
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respectively.  In many cases, a warning only affects a single entry in an
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archive, or is simply informing you that it's modifying an entry to comply
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with the settings provided.
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Unrecoverable warnings will always raise an error (ie, emit `'error'` on
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streaming actions, throw for non-streaming sync actions, reject the
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returned Promise for non-streaming async operations, or call a provided
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callback with an `Error` as the first argument).  Recoverable errors will
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raise an error only if `strict: true` is set in the options.
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Respond to (recoverable) warnings by listening to the `warn` event.
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Handlers receive 3 arguments:
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- `code` String.  One of the error codes below.  This may not match
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  `data.code`, which preserves the original error code from fs and zlib.
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- `message` String.  More details about the error.
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- `data` Metadata about the error.  An `Error` object for errors raised by
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  fs and zlib.  All fields are attached to errors raisd by tar.  Typically
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  contains the following fields, as relevant:
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  - `tarCode` The tar error code.
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  - `code` Either the tar error code, or the error code set by the
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    underlying system.
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  - `file` The archive file being read or written.
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  - `cwd` Working directory for creation and extraction operations.
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  - `entry` The entry object (if it could be created) for `TAR_ENTRY_INFO`,
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    `TAR_ENTRY_INVALID`, and `TAR_ENTRY_ERROR` warnings.
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  - `header` The header object (if it could be created, and the entry could
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    not be created) for `TAR_ENTRY_INFO` and `TAR_ENTRY_INVALID` warnings.
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  - `recoverable` Boolean.  If `false`, then the warning will emit an
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    `error`, even in non-strict mode.
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#### Error Codes
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* `TAR_ENTRY_INFO`  An informative error indicating that an entry is being
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  modified, but otherwise processed normally.  For example, removing `/` or
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  `C:\` from absolute paths if `preservePaths` is not set.
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* `TAR_ENTRY_INVALID` An indication that a given entry is not a valid tar
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  archive entry, and will be skipped.  This occurs when:
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  - a checksum fails,
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  - a `linkpath` is missing for a link type, or
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  - a `linkpath` is provided for a non-link type.
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  If every entry in a parsed archive raises an `TAR_ENTRY_INVALID` error,
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  then the archive is presumed to be unrecoverably broken, and
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  `TAR_BAD_ARCHIVE` will be raised.
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* `TAR_ENTRY_ERROR` The entry appears to be a valid tar archive entry, but
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  encountered an error which prevented it from being unpacked.  This occurs
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  when:
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  - an unrecoverable fs error happens during unpacking,
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  - an entry is trying to extract into an excessively deep
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    location (by default, limited to 1024 subfolders),
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  - an entry has `..` in the path and `preservePaths` is not set, or
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  - an entry is extracting through a symbolic link, when `preservePaths` is
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    not set.
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* `TAR_ENTRY_UNSUPPORTED`  An indication that a given entry is
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  a valid archive entry, but of a type that is unsupported, and so will be
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  skipped in archive creation or extracting.
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* `TAR_ABORT`  When parsing gzipped-encoded archives, the parser will
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  abort the parse process raise a warning for any zlib errors encountered.
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  Aborts are considered unrecoverable for both parsing and unpacking.
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* `TAR_BAD_ARCHIVE`  The archive file is totally hosed.  This can happen for
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  a number of reasons, and always occurs at the end of a parse or extract:
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  - An entry body was truncated before seeing the full number of bytes.
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  - The archive contained only invalid entries, indicating that it is
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    likely not an archive, or at least, not an archive this library can
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    parse.
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  `TAR_BAD_ARCHIVE` is considered informative for parse operations, but
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  unrecoverable for extraction.  Note that, if encountered at the end of an
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  extraction, tar WILL still have extracted as much it could from the
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  archive, so there may be some garbage files to clean up.
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Errors that occur deeper in the system (ie, either the filesystem or zlib)
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will have their error codes left intact, and a `tarCode` matching one of
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the above will be added to the warning metadata or the raised error object.
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Errors generated by tar will have one of the above codes set as the
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`error.code` field as well, but since errors originating in zlib or fs will
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have their original codes, it's better to read `error.tarCode` if you wish
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to see how tar is handling the issue.
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### Examples
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The API mimics the `tar(1)` command line functionality, with aliases
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for more human-readable option and function names.  The goal is that
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if you know how to use `tar(1)` in Unix, then you know how to use
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`require('tar')` in JavaScript.
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To replicate `tar czf my-tarball.tgz files and folders`, you'd do:
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```js
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tar.c(
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  {
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    gzip: <true|gzip options>,
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    file: 'my-tarball.tgz'
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  },
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  ['some', 'files', 'and', 'folders']
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).then(_ => { .. tarball has been created .. })
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```
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To replicate `tar cz files and folders > my-tarball.tgz`, you'd do:
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```js
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tar.c( // or tar.create
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  {
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    gzip: <true|gzip options>
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  },
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  ['some', 'files', 'and', 'folders']
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).pipe(fs.createWriteStream('my-tarball.tgz'))
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```
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To replicate `tar xf my-tarball.tgz` you'd do:
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```js
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tar.x(  // or tar.extract(
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  {
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    file: 'my-tarball.tgz'
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  }
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).then(_=> { .. tarball has been dumped in cwd .. })
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```
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To replicate `cat my-tarball.tgz | tar x -C some-dir --strip=1`:
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```js
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fs.createReadStream('my-tarball.tgz').pipe(
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  tar.x({
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    strip: 1,
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    C: 'some-dir' // alias for cwd:'some-dir', also ok
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  })
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)
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```
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To replicate `tar tf my-tarball.tgz`, do this:
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```js
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tar.t({
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  file: 'my-tarball.tgz',
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  onentry: entry => { .. do whatever with it .. }
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})
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```
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For example, to just get the list of filenames from an archive:
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```js
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const getEntryFilenames = async tarballFilename => {
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  const filenames = []
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  await tar.t({
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    file: tarballFilename,
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    onentry: entry => filenames.push(entry.path),
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  })
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  return filenames
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}
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```
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To replicate `cat my-tarball.tgz | tar t` do:
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```js
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fs.createReadStream('my-tarball.tgz')
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  .pipe(tar.t())
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  .on('entry', entry => { .. do whatever with it .. })
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```
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To do anything synchronous, add `sync: true` to the options.  Note
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that sync functions don't take a callback and don't return a promise.
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When the function returns, it's already done.  Sync methods without a
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file argument return a sync stream, which flushes immediately.  But,
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of course, it still won't be done until you `.end()` it.
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```js
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const getEntryFilenamesSync = tarballFilename => {
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  const filenames = []
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  tar.t({
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    file: tarballFilename,
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    onentry: entry => filenames.push(entry.path),
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    sync: true,
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  })
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  return filenames
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}
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```
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To filter entries, add `filter: <function>` to the options.
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Tar-creating methods call the filter with `filter(path, stat)`.
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Tar-reading methods (including extraction) call the filter with
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`filter(path, entry)`.  The filter is called in the `this`-context of
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the `Pack` or `Unpack` stream object.
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The arguments list to `tar t` and `tar x` specify a list of filenames
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to extract or list, so they're equivalent to a filter that tests if
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the file is in the list.
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For those who _aren't_ fans of tar's single-character command names:
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```
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tar.c === tar.create
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tar.r === tar.replace (appends to archive, file is required)
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tar.u === tar.update (appends if newer, file is required)
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tar.x === tar.extract
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tar.t === tar.list
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```
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Keep reading for all the command descriptions and options, as well as
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the low-level API that they are built on.
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### tar.c(options, fileList, callback) [alias: tar.create]
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Create a tarball archive.
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The `fileList` is an array of paths to add to the tarball.  Adding a
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directory also adds its children recursively.
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An entry in `fileList` that starts with an `@` symbol is a tar archive
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whose entries will be added.  To add a file that starts with `@`,
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prepend it with `./`.
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The following options are supported:
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- `file` Write the tarball archive to the specified filename.  If this
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  is specified, then the callback will be fired when the file has been
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  written, and a promise will be returned that resolves when the file
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  is written.  If a filename is not specified, then a Readable Stream
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  will be returned which will emit the file data. [Alias: `f`]
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- `sync` Act synchronously.  If this is set, then any provided file
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  will be fully written after the call to `tar.c`.  If this is set,
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  and a file is not provided, then the resulting stream will already
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  have the data ready to `read` or `emit('data')` as soon as you
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  request it.
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- `onwarn` A function that will get called with `(code, message, data)` for
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  any warnings encountered.  (See "Warnings and Errors")
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- `strict` Treat warnings as crash-worthy errors.  Default false.
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- `cwd` The current working directory for creating the archive.
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  Defaults to `process.cwd()`.  [Alias: `C`]
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- `prefix` A path portion to prefix onto the entries in the archive.
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- `gzip` Set to any truthy value to create a gzipped archive, or an
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  object with settings for `zlib.Gzip()` [Alias: `z`]
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- `filter` A function that gets called with `(path, stat)` for each
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  entry being added.  Return `true` to add the entry to the archive,
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  or `false` to omit it.
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- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
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  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
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  that `mtime` is still included, because this is necessary for other
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  time-based operations.  Additionally, `mode` is set to a "reasonable
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  default" for most unix systems, based on a `umask` value of `0o22`.
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- `preservePaths` Allow absolute paths.  By default, `/` is stripped
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  from absolute paths. [Alias: `P`]
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- `mode` The mode to set on the created file archive
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- `noDirRecurse` Do not recursively archive the contents of
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  directories. [Alias: `n`]
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- `follow` Set to true to pack the targets of symbolic links.  Without
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  this option, symbolic links are archived as such. [Alias: `L`, `h`]
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- `noPax` Suppress pax extended headers.  Note that this means that
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  long paths and linkpaths will be truncated, and large or negative
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  numeric values may be interpreted incorrectly.
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- `noMtime` Set to true to omit writing `mtime` values for entries.
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  Note that this prevents using other mtime-based features like
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  `tar.update` or the `keepNewer` option with the resulting tar archive.
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  [Alias: `m`, `no-mtime`]
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- `mtime` Set to a `Date` object to force a specific `mtime` for
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  everything added to the archive.  Overridden by `noMtime`.
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The following options are mostly internal, but can be modified in some
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advanced use cases, such as re-using caches between runs.
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- `linkCache` A Map object containing the device and inode value for
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  any file whose nlink is > 1, to identify hard links.
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- `statCache` A Map object that caches calls `lstat`.
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- `readdirCache` A Map object that caches calls to `readdir`.
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- `jobs` A number specifying how many concurrent jobs to run.
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  Defaults to 4.
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- `maxReadSize` The maximum buffer size for `fs.read()` operations.
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  Defaults to 16 MB.
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### tar.x(options, fileList, callback) [alias: tar.extract]
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Extract a tarball archive.
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The `fileList` is an array of paths to extract from the tarball.  If
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no paths are provided, then all the entries are extracted.
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If the archive is gzipped, then tar will detect this and unzip it.
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Note that all directories that are created will be forced to be
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writable, readable, and listable by their owner, to avoid cases where
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a directory prevents extraction of child entries by virtue of its
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mode.
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Most extraction errors will cause a `warn` event to be emitted.  If
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the `cwd` is missing, or not a directory, then the extraction will
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fail completely.
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The following options are supported:
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- `cwd` Extract files relative to the specified directory.  Defaults
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  to `process.cwd()`.  If provided, this must exist and must be a
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  directory. [Alias: `C`]
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- `file` The archive file to extract.  If not specified, then a
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  Writable stream is returned where the archive data should be
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  written. [Alias: `f`]
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- `sync` Create files and directories synchronously.
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- `strict` Treat warnings as crash-worthy errors.  Default false.
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- `filter` A function that gets called with `(path, entry)` for each
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  entry being unpacked.  Return `true` to unpack the entry from the
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  archive, or `false` to skip it.
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- `newer` Set to true to keep the existing file on disk if it's newer
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  than the file in the archive. [Alias: `keep-newer`,
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  `keep-newer-files`]
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- `keep` Do not overwrite existing files.  In particular, if a file
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  appears more than once in an archive, later copies will not
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  overwrite earlier copies. [Alias: `k`, `keep-existing`]
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- `preservePaths` Allow absolute paths, paths containing `..`, and
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  extracting through symbolic links.  By default, `/` is stripped from
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  absolute paths, `..` paths are not extracted, and any file whose
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  location would be modified by a symbolic link is not extracted.
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  [Alias: `P`]
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- `unlink` Unlink files before creating them.  Without this option,
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  tar overwrites existing files, which preserves existing hardlinks.
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  With this option, existing hardlinks will be broken, as will any
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  symlink that would affect the location of an extracted file. [Alias:
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  `U`]
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- `strip` Remove the specified number of leading path elements.
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  Pathnames with fewer elements will be silently skipped.  Note that
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  the pathname is edited after applying the filter, but before
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  security checks. [Alias: `strip-components`, `stripComponents`]
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- `onwarn` A function that will get called with `(code, message, data)` for
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  any warnings encountered.  (See "Warnings and Errors")
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- `preserveOwner` If true, tar will set the `uid` and `gid` of
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  extracted entries to the `uid` and `gid` fields in the archive.
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  This defaults to true when run as root, and false otherwise.  If
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  false, then files and directories will be set with the owner and
 | 
						|
  group of the user running the process.  This is similar to `-p` in
 | 
						|
  `tar(1)`, but ACLs and other system-specific data is never unpacked
 | 
						|
  in this implementation, and modes are set by default already.
 | 
						|
  [Alias: `p`]
 | 
						|
- `uid` Set to a number to force ownership of all extracted files and
 | 
						|
  folders, and all implicitly created directories, to be owned by the
 | 
						|
  specified user id, regardless of the `uid` field in the archive.
 | 
						|
  Cannot be used along with `preserveOwner`.  Requires also setting a
 | 
						|
  `gid` option.
 | 
						|
- `gid` Set to a number to force ownership of all extracted files and
 | 
						|
  folders, and all implicitly created directories, to be owned by the
 | 
						|
  specified group id, regardless of the `gid` field in the archive.
 | 
						|
  Cannot be used along with `preserveOwner`.  Requires also setting a
 | 
						|
  `uid` option.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` value for extracted
 | 
						|
  entries. [Alias: `m`, `no-mtime`]
 | 
						|
- `transform` Provide a function that takes an `entry` object, and
 | 
						|
  returns a stream, or any falsey value.  If a stream is provided,
 | 
						|
  then that stream's data will be written instead of the contents of
 | 
						|
  the archive entry.  If a falsey value is provided, then the entry is
 | 
						|
  written to disk as normal.  (To exclude items from extraction, use
 | 
						|
  the `filter` option described above.)
 | 
						|
- `onentry` A function that gets called with `(entry)` for each entry
 | 
						|
  that passes the filter.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `noChmod` Set to true to omit calling `fs.chmod()` to ensure that the
 | 
						|
  extracted file matches the entry mode.  This also suppresses the call to
 | 
						|
  `process.umask()` to determine the default umask value, since tar will
 | 
						|
  extract with whatever mode is provided, and let the process `umask` apply
 | 
						|
  normally.
 | 
						|
- `maxDepth` The maximum depth of subfolders to extract into. This
 | 
						|
  defaults to 1024. Anything deeper than the limit will raise a
 | 
						|
  warning and skip the entry. Set to `Infinity` to remove the
 | 
						|
  limitation.
 | 
						|
 | 
						|
The following options are mostly internal, but can be modified in some
 | 
						|
advanced use cases, such as re-using caches between runs.
 | 
						|
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 16 MB.
 | 
						|
- `umask` Filter the modes of entries like `process.umask()`.
 | 
						|
- `dmode` Default mode for directories
 | 
						|
- `fmode` Default mode for files
 | 
						|
- `dirCache` A Map object of which directories exist.
 | 
						|
- `maxMetaEntrySize` The maximum size of meta entries that is
 | 
						|
  supported.  Defaults to 1 MB.
 | 
						|
 | 
						|
Note that using an asynchronous stream type with the `transform`
 | 
						|
option will cause undefined behavior in sync extractions.
 | 
						|
[MiniPass](http://npm.im/minipass)-based streams are designed for this
 | 
						|
use case.
 | 
						|
 | 
						|
### tar.t(options, fileList, callback) [alias: tar.list]
 | 
						|
 | 
						|
List the contents of a tarball archive.
 | 
						|
 | 
						|
The `fileList` is an array of paths to list from the tarball.  If
 | 
						|
no paths are provided, then all the entries are listed.
 | 
						|
 | 
						|
If the archive is gzipped, then tar will detect this and unzip it.
 | 
						|
 | 
						|
If the `file` option is _not_ provided, then returns an event emitter that
 | 
						|
emits `entry` events with `tar.ReadEntry` objects.  However, they don't
 | 
						|
emit `'data'` or `'end'` events.  (If you want to get actual readable
 | 
						|
entries, use the `tar.Parse` class instead.)
 | 
						|
 | 
						|
If a `file` option _is_ provided, then the return value will be a promise
 | 
						|
that resolves when the file has been fully traversed in async mode, or
 | 
						|
`undefined` if `sync: true` is set.  Thus, you _must_ specify an `onentry`
 | 
						|
method in order to do anything useful with the data it parses.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `file` The archive file to list.  If not specified, then a
 | 
						|
  Writable stream is returned where the archive data should be
 | 
						|
  written. [Alias: `f`]
 | 
						|
- `sync` Read the specified file synchronously.  (This has no effect
 | 
						|
  when a file option isn't specified, because entries are emitted as
 | 
						|
  fast as they are parsed from the stream anyway.)
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `filter` A function that gets called with `(path, entry)` for each
 | 
						|
  entry being listed.  Return `true` to emit the entry from the
 | 
						|
  archive, or `false` to skip it.
 | 
						|
- `onentry` A function that gets called with `(entry)` for each entry
 | 
						|
  that passes the filter.  This is important for when `file` is set,
 | 
						|
  because there is no other way to do anything useful with this method.
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 16 MB.
 | 
						|
- `noResume` By default, `entry` streams are resumed immediately after
 | 
						|
  the call to `onentry`.  Set `noResume: true` to suppress this
 | 
						|
  behavior.  Note that by opting into this, the stream will never
 | 
						|
  complete until the entry data is consumed.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
 | 
						|
### tar.u(options, fileList, callback) [alias: tar.update]
 | 
						|
 | 
						|
Add files to an archive if they are newer than the entry already in
 | 
						|
the tarball archive.
 | 
						|
 | 
						|
The `fileList` is an array of paths to add to the tarball.  Adding a
 | 
						|
directory also adds its children recursively.
 | 
						|
 | 
						|
An entry in `fileList` that starts with an `@` symbol is a tar archive
 | 
						|
whose entries will be added.  To add a file that starts with `@`,
 | 
						|
prepend it with `./`.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `file` Required. Write the tarball archive to the specified
 | 
						|
  filename. [Alias: `f`]
 | 
						|
- `sync` Act synchronously.  If this is set, then any provided file
 | 
						|
  will be fully written after the call to `tar.c`.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `cwd` The current working directory for adding entries to the
 | 
						|
  archive.  Defaults to `process.cwd()`.  [Alias: `C`]
 | 
						|
- `prefix` A path portion to prefix onto the entries in the archive.
 | 
						|
- `gzip` Set to any truthy value to create a gzipped archive, or an
 | 
						|
  object with settings for `zlib.Gzip()` [Alias: `z`]
 | 
						|
- `filter` A function that gets called with `(path, stat)` for each
 | 
						|
  entry being added.  Return `true` to add the entry to the archive,
 | 
						|
  or `false` to omit it.
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths. [Alias: `P`]
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 16 MB.
 | 
						|
- `noDirRecurse` Do not recursively archive the contents of
 | 
						|
  directories. [Alias: `n`]
 | 
						|
- `follow` Set to true to pack the targets of symbolic links.  Without
 | 
						|
  this option, symbolic links are archived as such. [Alias: `L`, `h`]
 | 
						|
- `noPax` Suppress pax extended headers.  Note that this means that
 | 
						|
  long paths and linkpaths will be truncated, and large or negative
 | 
						|
  numeric values may be interpreted incorrectly.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
  [Alias: `m`, `no-mtime`]
 | 
						|
- `mtime` Set to a `Date` object to force a specific `mtime` for
 | 
						|
  everything added to the archive.  Overridden by `noMtime`.
 | 
						|
 | 
						|
### tar.r(options, fileList, callback) [alias: tar.replace]
 | 
						|
 | 
						|
Add files to an existing archive.  Because later entries override
 | 
						|
earlier entries, this effectively replaces any existing entries.
 | 
						|
 | 
						|
The `fileList` is an array of paths to add to the tarball.  Adding a
 | 
						|
directory also adds its children recursively.
 | 
						|
 | 
						|
An entry in `fileList` that starts with an `@` symbol is a tar archive
 | 
						|
whose entries will be added.  To add a file that starts with `@`,
 | 
						|
prepend it with `./`.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `file` Required. Write the tarball archive to the specified
 | 
						|
  filename. [Alias: `f`]
 | 
						|
- `sync` Act synchronously.  If this is set, then any provided file
 | 
						|
  will be fully written after the call to `tar.c`.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `cwd` The current working directory for adding entries to the
 | 
						|
  archive.  Defaults to `process.cwd()`.  [Alias: `C`]
 | 
						|
- `prefix` A path portion to prefix onto the entries in the archive.
 | 
						|
- `gzip` Set to any truthy value to create a gzipped archive, or an
 | 
						|
  object with settings for `zlib.Gzip()` [Alias: `z`]
 | 
						|
- `filter` A function that gets called with `(path, stat)` for each
 | 
						|
  entry being added.  Return `true` to add the entry to the archive,
 | 
						|
  or `false` to omit it.
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths. [Alias: `P`]
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 16 MB.
 | 
						|
- `noDirRecurse` Do not recursively archive the contents of
 | 
						|
  directories. [Alias: `n`]
 | 
						|
- `follow` Set to true to pack the targets of symbolic links.  Without
 | 
						|
  this option, symbolic links are archived as such. [Alias: `L`, `h`]
 | 
						|
- `noPax` Suppress pax extended headers.  Note that this means that
 | 
						|
  long paths and linkpaths will be truncated, and large or negative
 | 
						|
  numeric values may be interpreted incorrectly.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
  [Alias: `m`, `no-mtime`]
 | 
						|
- `mtime` Set to a `Date` object to force a specific `mtime` for
 | 
						|
  everything added to the archive.  Overridden by `noMtime`.
 | 
						|
 | 
						|
 | 
						|
## Low-Level API
 | 
						|
 | 
						|
### class tar.Pack
 | 
						|
 | 
						|
A readable tar stream.
 | 
						|
 | 
						|
Has all the standard readable stream interface stuff.  `'data'` and
 | 
						|
`'end'` events, `read()` method, `pause()` and `resume()`, etc.
 | 
						|
 | 
						|
#### constructor(options)
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `cwd` The current working directory for creating the archive.
 | 
						|
  Defaults to `process.cwd()`.
 | 
						|
- `prefix` A path portion to prefix onto the entries in the archive.
 | 
						|
- `gzip` Set to any truthy value to create a gzipped archive, or an
 | 
						|
  object with settings for `zlib.Gzip()`
 | 
						|
- `filter` A function that gets called with `(path, stat)` for each
 | 
						|
  entry being added.  Return `true` to add the entry to the archive,
 | 
						|
  or `false` to omit it.
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths.
 | 
						|
- `linkCache` A Map object containing the device and inode value for
 | 
						|
  any file whose nlink is > 1, to identify hard links.
 | 
						|
- `statCache` A Map object that caches calls `lstat`.
 | 
						|
- `readdirCache` A Map object that caches calls to `readdir`.
 | 
						|
- `jobs` A number specifying how many concurrent jobs to run.
 | 
						|
  Defaults to 4.
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 16 MB.
 | 
						|
- `noDirRecurse` Do not recursively archive the contents of
 | 
						|
  directories.
 | 
						|
- `follow` Set to true to pack the targets of symbolic links.  Without
 | 
						|
  this option, symbolic links are archived as such.
 | 
						|
- `noPax` Suppress pax extended headers.  Note that this means that
 | 
						|
  long paths and linkpaths will be truncated, and large or negative
 | 
						|
  numeric values may be interpreted incorrectly.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
- `mtime` Set to a `Date` object to force a specific `mtime` for
 | 
						|
  everything added to the archive.  Overridden by `noMtime`.
 | 
						|
 | 
						|
#### add(path)
 | 
						|
 | 
						|
Adds an entry to the archive.  Returns the Pack stream.
 | 
						|
 | 
						|
#### write(path)
 | 
						|
 | 
						|
Adds an entry to the archive.  Returns true if flushed.
 | 
						|
 | 
						|
#### end()
 | 
						|
 | 
						|
Finishes the archive.
 | 
						|
 | 
						|
### class tar.Pack.Sync
 | 
						|
 | 
						|
Synchronous version of `tar.Pack`.
 | 
						|
 | 
						|
### class tar.Unpack
 | 
						|
 | 
						|
A writable stream that unpacks a tar archive onto the file system.
 | 
						|
 | 
						|
All the normal writable stream stuff is supported.  `write()` and
 | 
						|
`end()` methods, `'drain'` events, etc.
 | 
						|
 | 
						|
Note that all directories that are created will be forced to be
 | 
						|
writable, readable, and listable by their owner, to avoid cases where
 | 
						|
a directory prevents extraction of child entries by virtue of its
 | 
						|
mode.
 | 
						|
 | 
						|
`'close'` is emitted when it's done writing stuff to the file system.
 | 
						|
 | 
						|
Most unpack errors will cause a `warn` event to be emitted.  If the
 | 
						|
`cwd` is missing, or not a directory, then an error will be emitted.
 | 
						|
 | 
						|
#### constructor(options)
 | 
						|
 | 
						|
- `cwd` Extract files relative to the specified directory.  Defaults
 | 
						|
  to `process.cwd()`.  If provided, this must exist and must be a
 | 
						|
  directory.
 | 
						|
- `filter` A function that gets called with `(path, entry)` for each
 | 
						|
  entry being unpacked.  Return `true` to unpack the entry from the
 | 
						|
  archive, or `false` to skip it.
 | 
						|
- `newer` Set to true to keep the existing file on disk if it's newer
 | 
						|
  than the file in the archive.
 | 
						|
- `keep` Do not overwrite existing files.  In particular, if a file
 | 
						|
  appears more than once in an archive, later copies will not
 | 
						|
  overwrite earlier copies.
 | 
						|
- `preservePaths` Allow absolute paths, paths containing `..`, and
 | 
						|
  extracting through symbolic links.  By default, `/` is stripped from
 | 
						|
  absolute paths, `..` paths are not extracted, and any file whose
 | 
						|
  location would be modified by a symbolic link is not extracted.
 | 
						|
- `unlink` Unlink files before creating them.  Without this option,
 | 
						|
  tar overwrites existing files, which preserves existing hardlinks.
 | 
						|
  With this option, existing hardlinks will be broken, as will any
 | 
						|
  symlink that would affect the location of an extracted file.
 | 
						|
- `strip` Remove the specified number of leading path elements.
 | 
						|
  Pathnames with fewer elements will be silently skipped.  Note that
 | 
						|
  the pathname is edited after applying the filter, but before
 | 
						|
  security checks.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `umask` Filter the modes of entries like `process.umask()`.
 | 
						|
- `dmode` Default mode for directories
 | 
						|
- `fmode` Default mode for files
 | 
						|
- `dirCache` A Map object of which directories exist.
 | 
						|
- `maxMetaEntrySize` The maximum size of meta entries that is
 | 
						|
  supported.  Defaults to 1 MB.
 | 
						|
- `preserveOwner` If true, tar will set the `uid` and `gid` of
 | 
						|
  extracted entries to the `uid` and `gid` fields in the archive.
 | 
						|
  This defaults to true when run as root, and false otherwise.  If
 | 
						|
  false, then files and directories will be set with the owner and
 | 
						|
  group of the user running the process.  This is similar to `-p` in
 | 
						|
  `tar(1)`, but ACLs and other system-specific data is never unpacked
 | 
						|
  in this implementation, and modes are set by default already.
 | 
						|
- `win32` True if on a windows platform.  Causes behavior where
 | 
						|
  filenames containing `<|>?` chars are converted to
 | 
						|
  windows-compatible values while being unpacked.
 | 
						|
- `uid` Set to a number to force ownership of all extracted files and
 | 
						|
  folders, and all implicitly created directories, to be owned by the
 | 
						|
  specified user id, regardless of the `uid` field in the archive.
 | 
						|
  Cannot be used along with `preserveOwner`.  Requires also setting a
 | 
						|
  `gid` option.
 | 
						|
- `gid` Set to a number to force ownership of all extracted files and
 | 
						|
  folders, and all implicitly created directories, to be owned by the
 | 
						|
  specified group id, regardless of the `gid` field in the archive.
 | 
						|
  Cannot be used along with `preserveOwner`.  Requires also setting a
 | 
						|
  `uid` option.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` value for extracted
 | 
						|
  entries.
 | 
						|
- `transform` Provide a function that takes an `entry` object, and
 | 
						|
  returns a stream, or any falsey value.  If a stream is provided,
 | 
						|
  then that stream's data will be written instead of the contents of
 | 
						|
  the archive entry.  If a falsey value is provided, then the entry is
 | 
						|
  written to disk as normal.  (To exclude items from extraction, use
 | 
						|
  the `filter` option described above.)
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `onentry` A function that gets called with `(entry)` for each entry
 | 
						|
  that passes the filter.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `noChmod` Set to true to omit calling `fs.chmod()` to ensure that the
 | 
						|
  extracted file matches the entry mode.  This also suppresses the call to
 | 
						|
  `process.umask()` to determine the default umask value, since tar will
 | 
						|
  extract with whatever mode is provided, and let the process `umask` apply
 | 
						|
  normally.
 | 
						|
- `maxDepth` The maximum depth of subfolders to extract into. This
 | 
						|
  defaults to 1024. Anything deeper than the limit will raise a
 | 
						|
  warning and skip the entry. Set to `Infinity` to remove the
 | 
						|
  limitation.
 | 
						|
 | 
						|
### class tar.Unpack.Sync
 | 
						|
 | 
						|
Synchronous version of `tar.Unpack`.
 | 
						|
 | 
						|
Note that using an asynchronous stream type with the `transform`
 | 
						|
option will cause undefined behavior in sync unpack streams.
 | 
						|
[MiniPass](http://npm.im/minipass)-based streams are designed for this
 | 
						|
use case.
 | 
						|
 | 
						|
### class tar.Parse
 | 
						|
 | 
						|
A writable stream that parses a tar archive stream.  All the standard
 | 
						|
writable stream stuff is supported.
 | 
						|
 | 
						|
If the archive is gzipped, then tar will detect this and unzip it.
 | 
						|
 | 
						|
Emits `'entry'` events with `tar.ReadEntry` objects, which are
 | 
						|
themselves readable streams that you can pipe wherever.
 | 
						|
 | 
						|
Each `entry` will not emit until the one before it is flushed through,
 | 
						|
so make sure to either consume the data (with `on('data', ...)` or
 | 
						|
`.pipe(...)`) or throw it away with `.resume()` to keep the stream
 | 
						|
flowing.
 | 
						|
 | 
						|
#### constructor(options)
 | 
						|
 | 
						|
Returns an event emitter that emits `entry` events with
 | 
						|
`tar.ReadEntry` objects.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `filter` A function that gets called with `(path, entry)` for each
 | 
						|
  entry being listed.  Return `true` to emit the entry from the
 | 
						|
  archive, or `false` to skip it.
 | 
						|
- `onentry` A function that gets called with `(entry)` for each entry
 | 
						|
  that passes the filter.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
 | 
						|
#### abort(error)
 | 
						|
 | 
						|
Stop all parsing activities.  This is called when there are zlib
 | 
						|
errors.  It also emits an unrecoverable warning with the error provided.
 | 
						|
 | 
						|
### class tar.ReadEntry extends [MiniPass](http://npm.im/minipass)
 | 
						|
 | 
						|
A representation of an entry that is being read out of a tar archive.
 | 
						|
 | 
						|
It has the following fields:
 | 
						|
 | 
						|
- `extended` The extended metadata object provided to the constructor.
 | 
						|
- `globalExtended` The global extended metadata object provided to the
 | 
						|
  constructor.
 | 
						|
- `remain` The number of bytes remaining to be written into the
 | 
						|
  stream.
 | 
						|
- `blockRemain` The number of 512-byte blocks remaining to be written
 | 
						|
  into the stream.
 | 
						|
- `ignore` Whether this entry should be ignored.
 | 
						|
- `meta` True if this represents metadata about the next entry, false
 | 
						|
  if it represents a filesystem object.
 | 
						|
- All the fields from the header, extended header, and global extended
 | 
						|
  header are added to the ReadEntry object.  So it has `path`, `type`,
 | 
						|
  `size`, `mode`, and so on.
 | 
						|
 | 
						|
#### constructor(header, extended, globalExtended)
 | 
						|
 | 
						|
Create a new ReadEntry object with the specified header, extended
 | 
						|
header, and global extended header values.
 | 
						|
 | 
						|
### class tar.WriteEntry extends [MiniPass](http://npm.im/minipass)
 | 
						|
 | 
						|
A representation of an entry that is being written from the file
 | 
						|
system into a tar archive.
 | 
						|
 | 
						|
Emits data for the Header, and for the Pax Extended Header if one is
 | 
						|
required, as well as any body data.
 | 
						|
 | 
						|
Creating a WriteEntry for a directory does not also create
 | 
						|
WriteEntry objects for all of the directory contents.
 | 
						|
 | 
						|
It has the following fields:
 | 
						|
 | 
						|
- `path` The path field that will be written to the archive.  By
 | 
						|
  default, this is also the path from the cwd to the file system
 | 
						|
  object.
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `myuid` If supported, the uid of the user running the current
 | 
						|
  process.
 | 
						|
- `myuser` The `env.USER` string if set, or `''`.  Set as the entry
 | 
						|
  `uname` field if the file's `uid` matches `this.myuid`.
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 1 MB.
 | 
						|
- `linkCache` A Map object containing the device and inode value for
 | 
						|
  any file whose nlink is > 1, to identify hard links.
 | 
						|
- `statCache` A Map object that caches calls `lstat`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths.
 | 
						|
- `cwd` The current working directory for creating the archive.
 | 
						|
  Defaults to `process.cwd()`.
 | 
						|
- `absolute` The absolute path to the entry on the filesystem.  By
 | 
						|
  default, this is `path.resolve(this.cwd, this.path)`, but it can be
 | 
						|
  overridden explicitly.
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `win32` True if on a windows platform.  Causes behavior where paths
 | 
						|
  replace `\` with `/` and filenames containing the windows-compatible
 | 
						|
  forms of `<|>?:` characters are converted to actual `<|>?:` characters
 | 
						|
  in the archive.
 | 
						|
- `noPax` Suppress pax extended headers.  Note that this means that
 | 
						|
  long paths and linkpaths will be truncated, and large or negative
 | 
						|
  numeric values may be interpreted incorrectly.
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
 | 
						|
 | 
						|
#### constructor(path, options)
 | 
						|
 | 
						|
`path` is the path of the entry as it is written in the archive.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `maxReadSize` The maximum buffer size for `fs.read()` operations.
 | 
						|
  Defaults to 1 MB.
 | 
						|
- `linkCache` A Map object containing the device and inode value for
 | 
						|
  any file whose nlink is > 1, to identify hard links.
 | 
						|
- `statCache` A Map object that caches calls `lstat`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths.
 | 
						|
- `cwd` The current working directory for creating the archive.
 | 
						|
  Defaults to `process.cwd()`.
 | 
						|
- `absolute` The absolute path to the entry on the filesystem.  By
 | 
						|
  default, this is `path.resolve(this.cwd, this.path)`, but it can be
 | 
						|
  overridden explicitly.
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `win32` True if on a windows platform.  Causes behavior where paths
 | 
						|
  replace `\` with `/`.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
- `umask` Set to restrict the modes on the entries in the archive,
 | 
						|
  somewhat like how umask works on file creation.  Defaults to
 | 
						|
  `process.umask()` on unix systems, or `0o22` on Windows.
 | 
						|
 | 
						|
#### warn(message, data)
 | 
						|
 | 
						|
If strict, emit an error with the provided message.
 | 
						|
 | 
						|
Othewise, emit a `'warn'` event with the provided message and data.
 | 
						|
 | 
						|
### class tar.WriteEntry.Sync
 | 
						|
 | 
						|
Synchronous version of tar.WriteEntry
 | 
						|
 | 
						|
### class tar.WriteEntry.Tar
 | 
						|
 | 
						|
A version of tar.WriteEntry that gets its data from a tar.ReadEntry
 | 
						|
instead of from the filesystem.
 | 
						|
 | 
						|
#### constructor(readEntry, options)
 | 
						|
 | 
						|
`readEntry` is the entry being read out of another archive.
 | 
						|
 | 
						|
The following options are supported:
 | 
						|
 | 
						|
- `portable` Omit metadata that is system-specific: `ctime`, `atime`,
 | 
						|
  `uid`, `gid`, `uname`, `gname`, `dev`, `ino`, and `nlink`.  Note
 | 
						|
  that `mtime` is still included, because this is necessary for other
 | 
						|
  time-based operations.  Additionally, `mode` is set to a "reasonable
 | 
						|
  default" for most unix systems, based on a `umask` value of `0o22`.
 | 
						|
- `preservePaths` Allow absolute paths.  By default, `/` is stripped
 | 
						|
  from absolute paths.
 | 
						|
- `strict` Treat warnings as crash-worthy errors.  Default false.
 | 
						|
- `onwarn` A function that will get called with `(code, message, data)` for
 | 
						|
  any warnings encountered.  (See "Warnings and Errors")
 | 
						|
- `noMtime` Set to true to omit writing `mtime` values for entries.
 | 
						|
  Note that this prevents using other mtime-based features like
 | 
						|
  `tar.update` or the `keepNewer` option with the resulting tar archive.
 | 
						|
 | 
						|
### class tar.Header
 | 
						|
 | 
						|
A class for reading and writing header blocks.
 | 
						|
 | 
						|
It has the following fields:
 | 
						|
 | 
						|
- `nullBlock` True if decoding a block which is entirely composed of
 | 
						|
  `0x00` null bytes.  (Useful because tar files are terminated by
 | 
						|
  at least 2 null blocks.)
 | 
						|
- `cksumValid` True if the checksum in the header is valid, false
 | 
						|
  otherwise.
 | 
						|
- `needPax` True if the values, as encoded, will require a Pax
 | 
						|
  extended header.
 | 
						|
- `path` The path of the entry.
 | 
						|
- `mode` The 4 lowest-order octal digits of the file mode.  That is,
 | 
						|
  read/write/execute permissions for world, group, and owner, and the
 | 
						|
  setuid, setgid, and sticky bits.
 | 
						|
- `uid` Numeric user id of the file owner
 | 
						|
- `gid` Numeric group id of the file owner
 | 
						|
- `size` Size of the file in bytes
 | 
						|
- `mtime` Modified time of the file
 | 
						|
- `cksum` The checksum of the header.  This is generated by adding all
 | 
						|
  the bytes of the header block, treating the checksum field itself as
 | 
						|
  all ascii space characters (that is, `0x20`).
 | 
						|
- `type` The human-readable name of the type of entry this represents,
 | 
						|
  or the alphanumeric key if unknown.
 | 
						|
- `typeKey` The alphanumeric key for the type of entry this header
 | 
						|
  represents.
 | 
						|
- `linkpath` The target of Link and SymbolicLink entries.
 | 
						|
- `uname` Human-readable user name of the file owner
 | 
						|
- `gname` Human-readable group name of the file owner
 | 
						|
- `devmaj` The major portion of the device number.  Always `0` for
 | 
						|
  files, directories, and links.
 | 
						|
- `devmin` The minor portion of the device number.  Always `0` for
 | 
						|
  files, directories, and links.
 | 
						|
- `atime` File access time.
 | 
						|
- `ctime` File change time.
 | 
						|
 | 
						|
#### constructor(data, [offset=0])
 | 
						|
 | 
						|
`data` is optional.  It is either a Buffer that should be interpreted
 | 
						|
as a tar Header starting at the specified offset and continuing for
 | 
						|
512 bytes, or a data object of keys and values to set on the header
 | 
						|
object, and eventually encode as a tar Header.
 | 
						|
 | 
						|
#### decode(block, offset)
 | 
						|
 | 
						|
Decode the provided buffer starting at the specified offset.
 | 
						|
 | 
						|
Buffer length must be greater than 512 bytes.
 | 
						|
 | 
						|
#### set(data)
 | 
						|
 | 
						|
Set the fields in the data object.
 | 
						|
 | 
						|
#### encode(buffer, offset)
 | 
						|
 | 
						|
Encode the header fields into the buffer at the specified offset.
 | 
						|
 | 
						|
Returns `this.needPax` to indicate whether a Pax Extended Header is
 | 
						|
required to properly encode the specified data.
 | 
						|
 | 
						|
### class tar.Pax
 | 
						|
 | 
						|
An object representing a set of key-value pairs in an Pax extended
 | 
						|
header entry.
 | 
						|
 | 
						|
It has the following fields.  Where the same name is used, they have
 | 
						|
the same semantics as the tar.Header field of the same name.
 | 
						|
 | 
						|
- `global` True if this represents a global extended header, or false
 | 
						|
  if it is for a single entry.
 | 
						|
- `atime`
 | 
						|
- `charset`
 | 
						|
- `comment`
 | 
						|
- `ctime`
 | 
						|
- `gid`
 | 
						|
- `gname`
 | 
						|
- `linkpath`
 | 
						|
- `mtime`
 | 
						|
- `path`
 | 
						|
- `size`
 | 
						|
- `uid`
 | 
						|
- `uname`
 | 
						|
- `dev`
 | 
						|
- `ino`
 | 
						|
- `nlink`
 | 
						|
 | 
						|
#### constructor(object, global)
 | 
						|
 | 
						|
Set the fields set in the object.  `global` is a boolean that defaults
 | 
						|
to false.
 | 
						|
 | 
						|
#### encode()
 | 
						|
 | 
						|
Return a Buffer containing the header and body for the Pax extended
 | 
						|
header entry, or `null` if there is nothing to encode.
 | 
						|
 | 
						|
#### encodeBody()
 | 
						|
 | 
						|
Return a string representing the body of the pax extended header
 | 
						|
entry.
 | 
						|
 | 
						|
#### encodeField(fieldName)
 | 
						|
 | 
						|
Return a string representing the key/value encoding for the specified
 | 
						|
fieldName, or `''` if the field is unset.
 | 
						|
 | 
						|
### tar.Pax.parse(string, extended, global)
 | 
						|
 | 
						|
Return a new Pax object created by parsing the contents of the string
 | 
						|
provided.
 | 
						|
 | 
						|
If the `extended` object is set, then also add the fields from that
 | 
						|
object.  (This is necessary because multiple metadata entries can
 | 
						|
occur in sequence.)
 | 
						|
 | 
						|
### tar.types
 | 
						|
 | 
						|
A translation table for the `type` field in tar headers.
 | 
						|
 | 
						|
#### tar.types.name.get(code)
 | 
						|
 | 
						|
Get the human-readable name for a given alphanumeric code.
 | 
						|
 | 
						|
#### tar.types.code.get(name)
 | 
						|
 | 
						|
Get the alphanumeric code for a given human-readable name.
 |