R: Extract or List Zip Archives

unzip {utils}

R Documentation

Extract or List Zip Archives

Description

Extract files from or list a zip archive.

Usage

unzip(zipfile, files = NULL, list = FALSE, overwrite = TRUE,
       junkpaths = FALSE, exdir = ".", unzip = "internal")

Arguments

`zipfile`	The pathname of the zip file: tilde expansion (see `path.expand`) will be performed.
`files`	A character vector of recorded filepaths to be extracted: the default is to extract all files.
`list`	If `TRUE`, list the files and extract none. The equivalent of `unzip -l`.
`overwrite`	If `TRUE`, overwrite existing files, otherwise ignore such files. The equivalent of `unzip -o`.
`junkpaths`	If `TRUE`, use only the basename of the stored filepath when extracting. The equivalent of `unzip -j`.
`exdir`	The directory to extract files to (the equivalent of `unzip -d`). It will be created if necessary.
`unzip`	The method to be used. An alternative is to use `getOption("unzip"`), which on a Unix-alike may be set to the path to a `unzip` program.

Value

If list = TRUE, a data frame with columns Name (character) Length (the size of the uncompressed file, usually integer, conceivably numeric with an external unzip) and Date (of class "POSIXct").

Otherwise for the "internal" method, a character vector of the filepaths extracted to, invisibly.

Note

This is a minimal implementation, principally designed for Windows' users to be able to unpack Windows binary packages without external software. It does not (for example) support Unicode filenames and large files as introduced in zip 3.0: for that use unzip = "unzip" with unzip 6.00 or later.

If unzip specifies a program, the format of the dates listed with list=TRUE is unknown (on Windows it can even depend on the current locale) and the return values could be NA or expressed in the wrong timezone or misinterpreted (the latter being far less likely as from unzip 6.00).

Source

The internal C code uses zlib and is in particular based on the contributed minizip application in the zlib sources (from http://zlib.net) by Gilles Vollant.