Specifically, we can pipe the archive file bytes to the decompressor as they arrive instead of needing the archive file in its entirety. In this article, we explored methods for downloading and extracting archives on the fly in Linux, bypassing the need to save them to disk. On the other hand, readers with Ubuntu OS versions earlier than 20.04 can install the bsdtar package. Therefore, readers with Ubuntu OS version 20.04 and onwards should install the libarchive-tools package to obtain the bsdtar binary. Note that for Ubuntu Linux users, the bsdtar binary resides in the libarchive-tools package ever since the OS version 20.04. Then, the -x option specifies the unarchiving operation, and the -v enables verbose mode so we get diagnostic messages from the command. Option -f- of the bsdtar command means that the input for the decompression comes from the standard input. zip file, we can download it using the same HTTP client command-line tool and pipe the output to the bsdtar command: $ wget -qO- | bsdtar -xvf. Using these local file headers, bsdtar can unarchive files as they arrive from the pipe instead of requiring the archive file in its entirety.įor example, given a link to a. Tools like the bsdtar command-line tool leverage this fact to unarchive. In fact, each of the files maintains a local file header that consists of the meta-information about that particular file. However, the index file at the end of the archive is not the sole source for the meta-information about the content of the archive. zip file decompressors do not accept input through the standard input. This arrangement appears to pose a problem because the decompressor would require the complete archive file before they can extract it. This index file contains information about the contents of the archive and tells the decompressor where to look. zip file format maintains an index file at the end of the archive file. tar.gz file waiting to be cleaned up after the commands. Then, the -L option makes the curl follows a redirect. This is mandatory since our standard output should consist of the archive file bytes only. The -s option prevents the curl command from printing diagnostic messages on the standard output. We can also substitute the wget command invocation with the curl: $ curl -s -L | tar xvzīy default, the curl command writes the response to the standard output stream. The -xz option runs unarchiving and decompression operations, and the -v option turns on verbose mode. The tar command then extracts the archive and places the content in the current directory. The second part of the command runs the tar command on the standard input stream, which will contain the downloaded bytes from the first part of the command. Additionally, we pass the -q option to silence the wget command so it doesn’t print any other messages on the standard output stream. Specifically, we write the downloaded bytes to the standard output using the -O- option. tar.gz file and pipe it to the standard output stream. Firstly, the command above uses the wget HTTP client command line tool to download the.
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