Freedup
Encyclopedia
freedup is a program
to scan directories or file lists for duplicate files
. The file lists may be provided to an input pipe
or internally generated using find
with provided options. There are more options to specify the search conditions more detailed. Other options influence the performed actions, i.e. whether to display only or to specify what kind of link under which circumstances. freedup first compares file sizes, then the MD5 signatures
, and before taking actions a byte-by-byte check for verification is performed. An interactive mode allows to decide individually which files to link soft
or hard
or to delete.
fdupes is written in POSIX compliant C
and is released under the GNU General Public License
.
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
to scan directories or file lists for duplicate files
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...
. The file lists may be provided to an input pipe
Pipeline (Unix)
In Unix-like computer operating systems , a pipeline is the original software pipeline: a set of processes chained by their standard streams, so that the output of each process feeds directly as input to the next one. Each connection is implemented by an anonymous pipe...
or internally generated using find
Find
In Unix-like and some other operating systems, find is a command-line utility that searches through one or more directory trees of a file system, locates files based on some user-specified criteria and applies a user-specified action on each matched file...
with provided options. There are more options to specify the search conditions more detailed. Other options influence the performed actions, i.e. whether to display only or to specify what kind of link under which circumstances. freedup first compares file sizes, then the MD5 signatures
MD5
The MD5 Message-Digest Algorithm is a widely used cryptographic hash function that produces a 128-bit hash value. Specified in RFC 1321, MD5 has been employed in a wide variety of security applications, and is also commonly used to check data integrity...
, and before taking actions a byte-by-byte check for verification is performed. An interactive mode allows to decide individually which files to link soft
Symbolic link
In computing, a symbolic link is a special type of file that contains a reference to another file or directory in the form of an absolute or relative path and that affects pathname resolution. Symbolic links were already present by 1978 in mini-computer operating systems from DEC and Data...
or hard
Hard link
In computing, a hard link is a directory entry that associates a name with a file on a file system. . The term is used in file systems which allow multiple hard links to be created for the same file. This has the effect of creating multiple names for the same file, causing an aliasing effect: e.g...
or to delete.
fdupes is written in POSIX compliant C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
and is released under the GNU General Public License
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
.
Similar programs
Other programs that can find duplicates and run under *nix:- clink
- duff
- dupseek
- dupefinder
- duper
- dupmerge
- epac
- fdf - Perl/c based and runs across platforms (Win32, *nix and possibly others)
- fdupe
- fdupes
- freedup - POSIX C compliant and runs across platforms (Windows with Cygwin, Linux, AIX, etc.)
- freedups
- fslint
- ftwin
- rdfind
- dupmerge - runs across platforms (Win32/64 with Cygwin, *nix, Linux etc.)
- DUFF (Windows Version)