Safe Way to Check Identical Files: A Comparison of 'fc' and 'cmp'

In the world of software development and system administration, it is common to deal with multiple copies of files and directories. Whether you are working on different versions of a project, synchronizing files between servers, or backing up important data, it is essential to ensure that the files are identical. In this article, we will introduce you to a command-line tool called fcmp, which can help you compare and verify the identity of files and directories.

What is fcmp?

fcmp is a lightweight and efficient file comparison tool that is part of the mc (Midnight Commander) suite. It is designed to compare files and directories recursively and report any differences between them. It supports various comparison modes, including binary and text comparison, and can handle files of different sizes and types.

Installation

To use fcmp, you first need to install the Midnight Commander package. The installation process varies depending on your operating system. For example, on Ubuntu or Debian, you can use the following command:

sudo apt-get install mc

On CentOS or Fedora, you can use:

sudo yum install mc

Usage

Once you have installed mc and its dependencies, you can use fcmp from the command line. The basic syntax is:

fcmp [options] source_directory target_directory

For example, to compare the contents of the src and dest directories, you can use:

fcmp src dest

By default, fcmp will compare files and directories recursively and report any differences. You can use various options to customize the comparison process.

Comparison Modes

fcmp supports two comparison modes:

• Text comparison: This mode is used for comparing text files, such as source code files or configuration files. It uses the diff utility to compare the contents of the files.
• Binary comparison: This mode is used for comparing binary files, such as executables or images. It uses the md5sum utility to calculate the MD5 checksum of the files and compares them.

You can specify the comparison mode using the -t option:

fcmp -t text_comparison source_directory target_directory

or

fcmp -t binary_comparison source_directory target_directory

Excluding Files

Sometimes, you may want to exclude certain files or directories from the comparison process. You can use the --exclude option to specify a list of patterns:

fcmp --exclude="*.log" source_directory target_directory

This will exclude all files that match the .log pattern from the comparison.

Ignoring Case

By default, fcmp is case-sensitive when comparing file names. You can use the --ignore-case option to ignore the case:

fcmp --ignore-case source_directory target_directory

In this article, we introduced you to fcmp, a powerful and efficient file comparison tool that is part of the Midnight Commander suite. We covered the basic usage, comparison modes, and some advanced options. By using fcmp, you can easily compare files and directories and ensure that they are identical.

References

• GNU Midnight Commander Manual
• GNU Midnight Commander: Comparing Files