fido (Format Identification for Digital Objects) is a command-line tool used to identify the formats of digital objects. It is developed by the Open Preservation Foundation and compares file signatures against the PRONOM registry to determine a file's format.

Installation

To install fido using pip, run the following:

pip install opf-fido

If the installation is successful, you should be able to run the following to see fido's help message:

fido -h

Identify an individual file's format

The simplest way to identify a single file's format using fido is by piping a filepath in as stdin using the ls command:

ls /mnt/dps/david/sample_file.abc | fido -input -

The above command converts the full filepath of sample_file.abc to stdin, which is then fed into the fido process itself. "-input -" tells fido to treat the stdin as a file to be analyzed.

In this example, fido is able to correctly identify sample_file.abc as a Microsoft Office Excel file, even though the .abc file extension is not one that is used by Excel. You can test this yourself by changing the file extension of any working file to a different extension and running it through fido. The fido output should show the original and correct file format information, whatever the extension.