GNU Sharutils
Encyclopedia
GNU Sharutils is a set of utilities to handle shell archive
s. The GNU shar utility produces a single file
out of many files and prepares them for transmission by electronic mail services, for example by converting binary file
s into plain ASCII
text. A shell archive is a collection of files that can be unpacked by the Bourne shell
. A wide range of features provide extensive flexibility in manufacturing shar archives and in specifying shar smartness. For example, shar may compress
files, uuencode
binary files, split long files and construct multi-part mailings, ensure correct unsharing order, and provide md5sum
or byte count verification.
GNU unshar scans a set of mail messages looking for the start of shell archives. It will automatically strip off the mail headers and other introductory text. The archive bodies are then unpacked by a copy of the shell. unshar may also process files containing concatenated shell archives.
Shar
In the Unix operating system, shar is an archive format. A shar file is a shell script, and executing it will recreate the files. This is a type of self-extracting archive file. It can be created with the Unix shar utility...
s. The GNU shar utility produces a single file
Computer file
A computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program and is usually based on some kind of durable storage. A file is durable in the sense that it remains available for programs to use after the current program has finished...
out of many files and prepares them for transmission by electronic mail services, for example by converting binary file
Binary file
A binary file is a computer file which may contain any type of data, encoded in binary form for computer storage and processing purposes; for example, computer document files containing formatted text...
s into plain ASCII
ASCII
The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
text. A shell archive is a collection of files that can be unpacked by the Bourne shell
Bourne shell
The Bourne shell, or sh, was the default Unix shell of Unix Version 7 and most Unix-like systems continue to have /bin/sh - which will be the Bourne shell, or a symbolic link or hard link to a compatible shell - even when more modern shells are used by most users.Developed by Stephen Bourne at AT&T...
. A wide range of features provide extensive flexibility in manufacturing shar archives and in specifying shar smartness. For example, shar may compress
Compress
Compress is a UNIX compression program based on the LZC compression method, which is an LZW implementation using variable size pointers as in LZ78.- Description of program :Files compressed by compress are typically given the extension .Z...
files, uuencode
Uuencode
Uuencoding is a form of binary-to-text encoding that originated in the Unix program uuencode, for encoding binary data for transmission over the uucp mail system.The name "uuencoding" is derived from "Unix-to-Unix encoding"...
binary files, split long files and construct multi-part mailings, ensure correct unsharing order, and provide md5sum
Md5sum
md5sum is a computer program that calculates and verifies 128-bit MD5 hashes, as described in RFC 1321. The MD5 hash functions as a compact digital fingerprint of a file. As with all such hashing algorithms, there is theoretically an unlimited number of files that will have any given MD5 hash...
or byte count verification.
GNU unshar scans a set of mail messages looking for the start of shell archives. It will automatically strip off the mail headers and other introductory text. The archive bodies are then unpacked by a copy of the shell. unshar may also process files containing concatenated shell archives.
See also
- sharSharIn the Unix operating system, shar is an archive format. A shar file is a shell script, and executing it will recreate the files. This is a type of self-extracting archive file. It can be created with the Unix shar utility...
- tar file format
- ar (Unix)Ar (Unix)The archiver is a Unix utility that maintains groups of files as a single archive file. Today, ar is generally used only to create and update static library files that the link editor or linker uses; it can be used to create archives for any purpose, but has been largely replaced by tar for...
- archive formats