{{Redir, Binary spanning, the mathematical optimization method, Binary splitting
File spanning is the ability to package a single file or data stream into separate files of a specified size. This task implies the ability to re-combine the package files back into the original file or data stream.
This is useful when saving large files onto smaller volumes or breaking large files up into smaller files for network messages of limited size (email, newsgroups). It also allows the creation of parity files such as
parchive
Parchive (a portmanteau of parity archive, and formally known as Parity Volume Set Specification) is an erasure code system that produces par files for checksum verification of data integrity, with the capability to perform data recovery operatio ...
(PAR) to verify and restore missing or corrupted package files. Another advantage with this is coping with file size limits on some file systems of removable media, or coping with volume size limits of things like
floppy disks
A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined wi ...
.
Sometimes the file spanning process is hidden as a secondary operation such as with file archivers. In this case, many smaller files are first packaged into a data stream and then repackaged into a multi-file archive.
File spanning software
Many file spanning utilities are available for nearly every OS and platform. Below are a few examples:
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PKZip
PKZIP is a file archiving computer program, notable for introducing the popular ZIP file format. PKZIP was first introduced for MS-DOS on the IBM-PC compatible platform in 1989. Since then versions have been released for a number of other ...
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WinZip
WinZip is a trialware file archiver and compressor for Microsoft Windows, macOS, iOS and Android. It is developed by WinZip Computing (formerly Nico Mak Computing), which is owned by Corel Corporation. The program can create archives in Zip ...
WinRAR
WinRAR is a trialware file archiver utility for Windows, developed by Eugene Roshal of win.rar GmbH. It can create and view archives in RAR or ZIP file formats, and unpack numerous archive file formats. To enable the user to test the integrit ...
* PAR/
Parchive
Parchive (a portmanteau of parity archive, and formally known as Parity Volume Set Specification) is an erasure code system that produces par files for checksum verification of data integrity, with the capability to perform data recovery operatio ...
*
split (Unix)
split is a utility on Unix, Plan 9, and Unix-like operating systems most commonly used to split a computer file into two or more smaller files.
History
The command first appeared in Version 3 Unix and is part of the X/Open Portability Guide s ...