fif

A command-line tool for detecting and optionally correcting files with incorrect extensions.

fif recursively scans the given directory and outputs a shell script to fix the name of any files with incorrect extensions. By default, fif will scan all non-hidden files in the given directory, and will ignore symlinks.

As fif prints a shell script to stdout rather than acting on the files directly, you may wish to redirect its output to a file, e.g. fif ~/Documents > output.sh. You can also pipe the output directly into your shell, e.g. fif ~/Documents | bash, although this is not recommended - you should look over fif's output and verify for yourself that it's not doing anything that will give you a headache before running it.

Installation

Cargo

cargo install --locked fif

To update, simply re-run this command, or use a tool like cargo-update.

Other backends

fif supports using infer or xdg-mime as its backend for looking up file types. By default, xdg-mime will be used on *nix systems (Linux, macOS, *BSD, etc.), and infer on all other systems.

xdg-mime should work on any *nix system with libmagic/file(1) installed, although I've only tested it on Linux and FreeBSD. infer should work on any system.

You can override the default backend for your system at compile time like so:

# xdg-mime
cargo install fif --features=xdg-mime-backend
# infer
cargo install fif --features=infer-backend

Of the supported backends, xdg-mime by far supports the most file types, as it uses the excellent Shared MIME Info database, whereas infer uses its own baked-in database. However, infer is also faster to load, if only by a few dozen milliseconds, and has no external dependencies.

Multithreading

It is also possible to disable multithreading by installing without default features:

cargo install fif --no-default-features

Usage

See fif --help for more.

The basics

The simplest way to use fif looks like this:

fif ~/Downloads

This command will scan all non-hidden files in your ~/Downloads directory.

You can also manually specify a set of extensions to use:

fif -e jpeg,jpg,zip,docx ~/Documents

Or a set of extensions - for example, to scan files with image extensions (jpg, png, gif, bmp...):

fif -E images ~/Pictures

Output

By default, fif will output a bash script (or PowerShell script on Windows) that can be used to fix all the files it found with incorrect file extensions.

You might find it useful to output this script to a file (rather than to stdout):

fif -E images ~/Pictures > output.sh

You can also manually specify an output format to use:

fif -O powershell ~/Documents > output.ps1

Logging

By default, fif will log any warnings and/or errors encountered during execution. This can be changed with the -v flag:

# also log info
fif -v ~/Downloads
# ...and debug
fif -vv ~/Downloads
# ...and trace
fif -vvv ~/Downloads

The verbosity of the logging can be modified by the RUST_LOG to one of: trace, debug, info, warn, error.

For example:

RUST_LOG=debug fif ~/Downloads

The five logging levels are used as follows:

Level	Description	Example
error	Errors that cause fif to stop running	fif was unable to open the provided directory
warn	Warnings that don't cause fif to stop running	fif was unable to determine the mime type of a given file
info	Information pertaining to fif's status	The provided directory was scanned without issue, and no files are in need of renaming
debug	Debug information - usually not important to end users	The list of extensions fif will consider
trace	Trace info - usually not important to end users	"Found 15 items to check", "Scan successful", etc.