dp

dp duplicates files and directories in place, like duplicating an item in a file manager.

It is meant for quick local duplication with predictable file names, not for archiving or backups.

Installation

go install github.com/CatsDeservePets/dp@latest

Usage

usage: dp [-v] source ...
  -v	cause dp to be verbose, showing files as they are duplicated

Semantics

dp writes each duplicate next to its source path. If the generated name already exists, it picks the next available duplicate name.

By default, dp uses Finder-like names:

file.txt        -> file copy.txt
file copy.txt   -> file copy 2.txt
file copy 2.txt -> file copy 3.txt

Path contents are duplicated roughly like cp -R: directories are traversed recursively, symlinks are not followed, and regular files are copied. dp preserves permission bits, but not ownership, timestamps, ACLs, or extended attributes.

Each command-line argument is handled independently. If duplicating one argument fails, dp reports the error and continues with the next argument.

Naming

Duplicate names can be configured using the environment variables $DUPFMT_FIRST and $DUPFMT_NUMBERED.

The following placeholders are supported:

%f    file name, including extension
%b    file stem, i.e. file name without extension
%e    extension, including the dot
%n    duplicate number

$DUPFMT_FIRST describes the first duplicate name and must not contain %n. $DUPFMT_NUMBERED describes the numbered names that follow and must contain exactly one %n, preceded by fixed text.

Both formats must use the same shape: either %f for the whole file name, or %b and %e for stem and extension.

When splitting a file name, the extension starts at the first dot after any leading dots:

archive.tar.gz -> archive copy.tar.gz
.bashrc        -> .bashrc copy

Example formats

Finder-like (default):

DUPFMT_FIRST="%b copy%e"
DUPFMT_NUMBERED="%b copy %n%e"

file.txt -> file copy.txt -> file copy 2.txt

Explorer-like:

DUPFMT_FIRST="%b - Copy%e"
DUPFMT_NUMBERED="%b - Copy (%n)%e"

file.txt -> file - Copy.txt -> file - Copy (2).txt

Nautilus-like:

DUPFMT_FIRST="%b (Copy)%e"
DUPFMT_NUMBERED="%b (Copy %n)%e"

file.txt -> file (Copy).txt -> file (Copy 2).txt

Emacs-like:

DUPFMT_FIRST="%f.~1~"
DUPFMT_NUMBERED="%f.~%n~"

file.txt -> file.txt.~1~ -> file.txt.~2~